Search

Rationale: This study aimed to report an uncommon site of origin of a rare head-and-neck cancer, namely malignant granular cell tumour. Patient Concerns: An 89-year-old female patient complained of persistent pharyngodynia and odynophagia for two months. Diagnosis: Upon clinical examination, the right palatine tonsil was larger and palpably firmer than the contralateral. An incisional biopsy of the lesion was performed under local anaesthesia revealing malignant granular cell tumour. A contrast-enhanced computed tomography (CECT) scan of the head and neck and an 18F-fluoro-2-deoxy-D-glucose positron emission tomography (PET) scan confirmed the presence of a pathologic appearance of the right palatine tonsil without nodal or distant metastasis. Treatment: Following a multidisciplinary consultation and the patient's informed permission, a right tonsillectomy extended to the constrictor muscle fibres of the upper pharynx was performed. Outcomes: The tumour was staged as pT2 R0 cN0 M0, according to the AJCC 8th edition for soft-tissue tumours of the head and neck. Due to the early stage and the radicality of surgery, no further adjuvant treatments were provided. The patient is currently followed up with no evidence of disease one year post-operatively. Take-away Lessons: Granular cell tumours are rare mesenchymal tumours, firstly described by the pathologist Abrikossoff in 1926. This type of tumour constitutes approximately 0.5% of all soft-tissue tumours, and can affect any part of the body, with the head and neck being the most frequently involved site. The tonsil is an extremely rare localisation of this cancer. The differential diagnosis of unilateral tonsillar enlargement should also include this histological entity. [ABSTRACT FROM AUTHOR]

Cavernous sinus tumours comprise 0.1–0.2% of all intracranial tumours, and are most commonly meningiomas or schwannomas. Central nervous system and cranial nerve granular cell tumours (GCTs) are extremely rare. We report the tenth case of a GCT arising from a cranial nerve, and the second case reported in a cavernous sinus location, and review the literature. A 67-year-old man presented with right sided trigeminal neuralgia. Imaging findings suggested a trigeminal schwannoma and he was treated with CyberKnife radiosurgery. Over a period of 41 months follow up, there was a progression in both symptoms and imaging findings, requiring debulking surgery. Histopathology identified a GCT. This is the first case of a cranial nerve GCT treated with stereotactic radiosurgery. Trigeminal nerve GCTs are a rare differential in cases of presumed schwannomas. [ABSTRACT FROM AUTHOR]

The cytomorphological features of benign mesenchymal tumours of the tongue have rarely been reported. Herein, we present the cytomorphological features of adult‐type rhabdomyoma, which occurred in the tongue of a female patient, and granular cell tumour (GCT), which occurred in the tongue of a male patient; both patients were in their mid‐50s. The cytological features of the adult‐type rhabdomyoma case included large polygonal to ovoid cells with abundant and granular cytoplasm with predominantly peripherally located, uniform, round to oval nuclei and small nucleoli. Cross‐striation and crystalline intracytoplasmic structures were not seen. The cytological features of the GCT case included large cells with abundant granular pale cytoplasm, small round nuclei and small distinct nucleoli. The cytological differential diagnoses of these tumours overlap; thus, the cytological findings of the different entities included in their differential diagnoses are discussed. [ABSTRACT FROM AUTHOR]

This article provides a broad overview of oral potentially malignant disorders (OPMD) and associated entities. The review opens with an update on the terminology surrounding OPMD before summarizing the lesions and conditions currently recognized as OPMD by the World Health Organization (WHO). Approaches to diagnosing oral epithelial dysplasia (OED) are discussed in the context of the WHO's recently modified architectural and cytological criteria for OED. The spectrum of reactive epithelial changes – which may mimic OED - is explored for comparison. The review then focuses on four significant OPMD - proliferative verrucous leukoplakia, oral submucous fibrosis, HPV-associated OED, and oral lichen planus – with clinical and histopathological examples. Next, potential pitfalls - non-preneoplastic lesions that can mimic OPMD clinically and histopathologically - are highlighted; these include chronic hyperplastic candidosis, verruciform xanthoma, granular cell tumour, and hairy leukoplakia. Molecular tests for identifying and stratifying OPMD are commented on briefly as - to date - histopathology remains the most reliable prognosticator. Clinicopathological correlation is critical to accurate histopathological diagnosis, risk stratification, and clinical management. The review closes by highlighting clinical features – e.g., associated redness – indicative of high risk. [ABSTRACT FROM AUTHOR]

Purpose: Granular cell tumours (GCTs) of the pancreas are mostly benign and exceptionally rare, with no unique identifying radiological features. Following a case discussion of a patient with GCT, a comprehensive review of available literature was conducted to identify the common diagnostic features associated with GCT. Methods: Following a case report identified in our institution, a systematic review was conducted by two authors in accordance with Preferred Reporting Items for Systematic review and Meta-Analysis protocols (PRISMA) guidelines. Databases MEDLINE, EMBASE, Scopus, World of Science, and grey literature were searched on August 2021. Inclusion criteria were histopathology diagnosed granular cell tumour of the pancreas. Results: A 37-year-old male presented with 1 month of abdominal pain and an MRI demonstrating a dilated main pancreatic duct, distal parenchymal atrophy, but no focal lesion. Repeat MRI at 6 months re-demonstrated similar findings and subsequent endoscopic ultrasound was suspicious for main duct IPMN. Following multidisciplinary team discussion, a spleen-preserving distal pancreatectomy was performed. Histopathology demonstrated granular cell tumour with cells diffusely positive for S100 and no malignant transformation. 11 case reports were identified in the literature with diagnosis confirmed on tissue histopathology based on positive immunohistochemical staining for S-100 protein. Eight patients presented with gastrointestinal symptoms with abdominal pain the main presenting complaint (50%). 10 patients underwent CT with portal venous contrast and all underwent endoscopic examination. Imaging findings were similar in five studies for EUS which demonstrated a hypoechoic lesion with homogenous appearance. On non-contrast CT GCT was iso-enhancing, and with portal venous contrast demonstrated hypo-enhancement that gradually enhanced on late phases. Pre-operative diagnosis of pancreatic carcinoma was described in six cases based on imaging and biopsy, resulting in progression to surgical resection. Nine patients were managed surgically and no complications identified on follow-up (6–52 months). Conclusion: The currently proposed management pathway includes EUS with biopsy and CT, and surgical resection recommended due to malignancy risk. Improved sample collection with EUS-FNA and microscopic assessment utilising S-100 immunohistochemistry may improve pre-operative diagnosis. Limitations include rare numbers in reported literature and short follow-up not allowing an assessment of GCT’s natural history and malignancy risk. Additional cases would expand the current dataset of GCTs of the pancreas, so that surgical resection may be avoided in the future. [ABSTRACT FROM AUTHOR]

Simple Summary: Intracranial granular cell tumours are rare tumours of unknown cellular origin. In this case series. we describe three dogs with neurological signs that had magnetic resonance imaging of the brain, and were diagnosed with granular cell tumours through histopathological and histochemical studies. Magnetic resonance imaging characteristics were atypical, showing hypointense lesions on T2-weighted images in all cases. Immunohistochemical studies helped in characterising the tumours and excluded a Schwann cell origin. The findings of this case series indicate that granular cell tumours can be hypointense on T2-weighted magnetic resonance images, and that the cell of origin remains to be determined. Intracranial granular cell tumours (GCT) are uncommon neoplasms of uncertain cellular origin that are rarely reported in dogs. This case series describes three aged dogs that presented with neurological signs in which magnetic resonance (MR) imaging revealed plaquelike extra-axial lesions that were hypointense on T2-weighted (T2w) images. The surgical biopsy of the lesions and necropsies were followed by histochemical characterisation with periodic acid–Schiff (PAS) staining and immunohistochemistry with ubiquitin, S-100, and SOX-10 to elucidate the cellular origin. The immunohistochemical study indicated that these intracranial GCTs were not of Schwann cell origin. In conclusion, GCTs should be considered a differential diagnosis of intracranial, extra-axial hypointense brain lesions on T2w MR images. [ABSTRACT FROM AUTHOR]

Granular cell tumour (GCT) is a relatively rare, benign tumour. The cells of a GCT are composed of large polygonal cells containing numerous eosinophilic granules in the cytoplasm and are thought to be of neural origin. GCT can occur anywhere on the body, but most commonly it is located on the tongue. GCT possess the potential for malignant transformation, and as such should be resected; the risk of malignant transformation is estimated to be 1%–2%. Patients generally do not require routine follow-up following excision with clear margins. Here, we present a case of a GCT of the tongue which had been present for 4 years in an otherwise healthy 35-year-old male. The lesion had been stable in size and appearance, and the patient was asymptomatic. An incision biopsy of the lesion revealed findings consistent with a GCT, and the patient underwent a wide local excision shortly after incision biopsy. [ABSTRACT FROM AUTHOR]

Granular cell tumours (GCTs) are uncommon neuroectodermally derived tumours. Vulvar location is rare with 134 reported cases presenting as a non-specific vulvar mass. They are of low malignant potential and management is local excision. They have a high local recurrence rate if incompletely excised. The GCT diagnosis is often retrospective due to its rarity, its non-specific presenting symptoms and numerous differentials. Here we descibe the case of a 31-year-old woman presenting after an asymptomatic right labium majus mass was noted during a postnatal visit. This was imaged with magentic resonance imaging (MRI) and a biopsy was inconclusive. She was referred for subspecialty consultation at the Chris O'Brien Lifehouse. The lesion was five centimetres, overlying the pubis and inferolateral to the clitoris with no skin changes or epidermal attachment. Wide local excision was performed. Histopathology showed GCT features with no malignant characteristics, but positive margins. Despite positive margins, the decision was made to not complete re-excision and observe for recurrence. This was an unusual case in a young postpartum woman. It highlights the need for clinical suspicion of this tumour type during a postpartum examination and the need for nuanced decision making regarding re-excision based on individual patient needs despite recurrence risk. [ABSTRACT FROM AUTHOR]

Rationale: Granular cell tumours (GCTs) of the tongue are a rare, soft tissue pathological entity at young ages. This case report aims to present one such case. Patient Concerns: A 16-year-old female patient sought treatment for a small, slow-growing, painless nodule in the dorsum of the tongue since six months. She underwent successful orthodontic treatment in recent past and is in the retention phase. Diagnosis: Excisional biopsy revealed the lesion to be a GCT under histopathology. Treatment: The patient was treated for an abnormal, small, slow-growing, painless nodule in the dorsum of the tongue. Outcomes: The patient had satisfactory esthetics and early diagnosis. The active intervention dispelled the confusion about the role of trauma and orthodontics appliance in the etiology of GCT in this particular case to the patient. Take-away Lessons: GCT can occur at any age. Early diagnosis and corrective surgery would help to avoid late complications.

Granular cell tumours are uncommon acquired benign tumours of nerve sheath origin that are usually seen in the head and neck region and upper aero-digestive tract. They usually present as solitary small sized nodules in middle age. The tumour is usually benign and composed of sheets of large sized cells with abundant granular cytoplasm containing lysosomal macro-inclusions known as pustulo-ovoid bodies of Milian (POB) that represent the heterogeneity of the lysosomes. No well-established criteria for malignancy have been described for this tumour. In this article, we have discussed a rare case of granular cell tumour of the penis with its characteristic histomorphology and immunohistochemistry and relevant differential diagnosis.

Introduction: Granular cell tumour (GCT), also called an Abrikossoff tumour, is a relatively rare neoplasm that usually develops between the fourth and sixth decades of life, with a slightly higher prevalence among female patients. Most GCTs are asymptomatic and are usually reported as incidental findings from endoscopy. Histologically, GCTs are composed of large polygonal cells containing numerous eosinophilic granules. Case presentation: A 65-year-old woman without any symptoms was admitted for a preventative colonoscopy. The biopsy revealed sessile serrated adenomas (adenomatous polyps) with low-grade dysplasia. The lesion in the caecum showed an intestinal mucosa with a subepithelial tumour, which was found to be positive for S-100 protein and could correspond to Abrikossoff's tumour. Conclusions: Due to the rare occurrence of colorectal Abrikossoff tumours in the colon, there are very few reported cases, especially in male patients. A colorectal GCT is a sporadic submucosal tumour that usually follows a benign course. Malignant GCT is extremely rare. The final diagnosis of GCT can be based on endoscopic biopsy and histopathological examinations. The basis of benign GCT treatment is endoscopic resection, which often leads to a cure. [ABSTRACT FROM AUTHOR]

Granular cell tumours (GCTs) are rare submucosal lesions, thought to develop from Schwann cells, characterised by large polygonal cells with abundant lysosomes. The objectives of this study are to investigate whether GCTs have an antigen-presenting cell (APC) phenotype or a neural crest phenotype using immunohistochemistry and to compare expression profiles with Schwannomas. Immunoreactivity to CD68, HLA-DR, CD163, CD40 and CD11c (APC phenotype) and markers of neural crest cell (NCC) origin S100, SOX10, NSE and GAP43 in 23 cases of GCTs and 10 cases of Schwannomas were evaluated. RT-qPCR was used to identify a possible NCC developmental phenotype in 6 cases of GCTs. GAP43 was identified as a new NCC marker for GCTs, and some evidence was found for an APC phenotype from CD68 and HLA-DR immunoreactivity. RT-qPCR failed to identify an NCC developmental phenotype of GCTs, likely due to technical issues. [ABSTRACT FROM AUTHOR]

Intracranial granular cell tumours (GCT) are uncommon neoplasms of uncertain cellular origin that are rarely reported in dogs. This case series describes three aged dogs that presented with neurological signs in which magnetic resonance (MR) imaging revealed plaquelike extra-axial lesions that were hypointense on T2-weighted (T2w) images. The surgical biopsy of the lesions and necropsies were followed by histochemical characterisation with periodic acid–Schiff (PAS) staining and immunohistochemistry with ubiquitin, S-100, and SOX-10 to elucidate the cellular origin. The immunohistochemical study indicated that these intracranial GCTs were not of Schwann cell origin. In conclusion, GCTs should be considered a differential diagnosis of intracranial, extra-axial hypointense brain lesions on T2w MR images.

The case of a 5-year-old intact female Pitbull Terrier with a granular cell tumour (GCT) of the mammary gland is presented. The dog was admitted for surgical removal of a non-painful lump assumed to be a fibroadenoma. Histological and immunohistochemical findings leading to the diagnosis consisted of polygonal tumour cells with well-defined cell borders and granular cytoplasm, staining positively with neuron-specific enolase (NSE) and protein S100 and negatively for cytokeratin AE1-AE3. Some important points in the diagnostic and therapeutic approach to this uncommon neoplasm are discussed. To our best knowledge this is the first case of such tumour in the mammary gland described in the veterinary literature.

Les tumeurs à cellules granuleuses sont rares aux nerfs périphériques représentant 0,029 % des spécimens anatomopathologiques. Seuls 5 cas d'atteinte du nerf ulnaire, considéré comme l'atteinte la plus fréquente, ont été publiés. Une femme antillaise de 32 ans présentait une douleur importante au bras accompagné d'un déficit des interosseux. Le bilan d'imagerie était en faveur d'un Schwannome, mais en peropératoire, a été retrouvée une tumeur intraneurale, inextirpable. La biopsie conclut à une tumeur à cellule granuleuse. Une simple surveillance a été instaurée, mais sont apparus dans les deux ans, une aggravation des douleurs, de la gêne et une augmentation en taille. Une résection du nerf avec des marges saines a été effectuée. La reconstruction s'est faite par greffe du nerf sural au bras associée à une neurotisation de la branche motrice du nerf ulnaire par le nerf interosseux antérieur. À deux ans de recul, il n'y a pas de récidive. Il existe une hypersensibilité au niveau de la cicatrice. On observe une récupération sensitive de l'annulaire, mais pas de récupération motrice de la main. Il existe une récupération légère des fléchisseurs profonds aggravant la griffe ulnaire. Les 5 cas publiés ont eu une prise en charge différente (biopsie uniquement, résection, résection et greffe) avec de résultats modestes. Il n'y a pas de traitement recommandé. Notre cas est le seul au niveau du bras. Nous avons pu effectuer une résection complète, mais les résultats fonctionnels sont pauvres. Le traitement des tumeurs à cellules granuleuses est indiqué, si elles sont symptomatiques, mais aucun traitement particulier n'est recommandé. Granular cell tumours are extremely rare on peripheral nerves, with an incidence of 0.029% of pathologic samples. In a literature review, we found only 5 cases involving the ulnar nerve, although considered the most frequently involvement nerve. A 32 year-old female from the French West Indies presented a severe arm pain with deficit of interosseous hand muscles. Imaging studies were in favour of a Schwanoma, but during surgery, we found an unremovable intra-neural tumour. Nerve biopsy revealed a granular cell tumour. Initial decision was observation only. However, within two years, tumour increased in size, along with pain aggravation and functional deficit. We performed a nerve resection (with adequate margins) with reconstruction using sural nerve graft associated with a neurotisation of the motor branch with the anterior interosseus nerve. At two years follow-up, no recurrence was observed. The scar is hypersensitive with moderate neuropathic pain. There is a sensory reinnervation of the fourth finger, with no motor recovery of the hand. We observed a slight recovery of flexor profundus tendons, which, in turn increased the claw hand. The five cases described in the literature were managed differently (biopsy only, excision, excision with reconstruction), with modest results. There is no recommended treatment. Our case is the first at arm level. We were able to perform complete resection, but functional result is poor. Granular cell tumours require treatment if symptomatic (pain, function loss), but, at the moment, there is no recommended treatment. [ABSTRACT FROM AUTHOR]

Rationale: Granular cell tumours (GCTs) of the tongue are a rare, soft tissue pathological entity at young ages. This case report aims to present one such case.Patient Concerns: A 16-year-old female patient sought treatment for a small, slow-growing, painless nodule in the dorsum of the tongue since six months. She underwent successful orthodontic treatment in recent past and is in the retention phase.Diagnosis: Excisional biopsy revealed the lesion to be a GCT under histopathology.Treatment: The patient was treated for an abnormal, small, slow-growing, painless nodule in the dorsum of the tongue.Outcomes: The patient had satisfactory esthetics and early diagnosis. The active intervention dispelled the confusion about the role of trauma and orthodontics appliance in the etiology of GCT in this particular case to the patient.Take-away Lessons: GCT can occur at any age. Early diagnosis and corrective surgery would help to avoid late complications. [ABSTRACT FROM AUTHOR]

The cytological features of granular cell tumour (GCT) are generally quite typical but, in some cases, the fine needle aspiration cytology (FNAC) diagnosis of GCT may be difficult or impossible because of unusual sites of onset or equivocal cytological features. In this report, two GCTs with atypical FNAC features are described in order to investigate the causes and provide possible diagnostic tips. From a series of nine histologically proven GCTs, two inconclusive FNAC cases were retrieved. Smears were poorly cellular showing isolated naked nuclei, anisonucleosis, granular chromatin and occasional small nucleoli. The background was finely granular in one case. Histological controls of these cases revealed marked fibrosis. Tumour‐associated fibrosis in GCT is variable and does not seem to influence clinical behaviour but it influences the harvest and the integrity of granular cells collected by FNAC. When GCT smears are poorly cellular, attention should be paid to the granular background and to the few granular cells, if any, as they might be the only features to suggest a GCT. Fine needle aspiration cytology of granular cell tumour (GCT) may be hampered by scanty cellularity and equivocal cytological features. Tumour‐associated fibrosis in GCT is variable and may influence the harvest and the integrity of granular cells collected by fine needle aspiration. When GCT smears are equivocal and poorly cellular, attention should be paid to the granular background and to the few granular cells, if any, as they may suggest a GCT. [ABSTRACT FROM AUTHOR]

The pathologist's approach to gastroesophageal mesenchymal tumours has changed dramatically during the last 25 years. In particular, gastrointestinal stromal tumour (GIST) has evolved from a wastebasket mesenchymal tumour category to a precisely defined entity with an increasingly detailed genetic subclassification. This subclassification has brought gastrointestinal mesenchymal neoplasia into the realm of precision medicine, with specific treatments optimised for particular genetic subtypes. Molecular genetic data have also greatly improved our understanding of oesophageal mesenchymal tumours, including the discovery that so‐called 'giant fibrovascular polyps' in fact represent a clinically distinctive presentation of well‐differentiated liposarcoma. Here, we will focus on gastroesophageal mesenchymal tumours for which there have been recent developments in classification, molecular genetics or tumour biology: granular cell tumour, 'giant fibrovascular polyp'/well‐differentiated liposarcoma, plexiform fibromyxoma, gastroblastoma and, of course, GIST. [ABSTRACT FROM AUTHOR]

Granular cell tumour is a rare, mostly benign, soft tissue, neuroectodermal tumour, most commonly seen in the skin and peripheral soft tissue. There are no publications to date of PSMA-PET avidity in a granular cell tumour. In this 60 year old male, staging PSMA-PET for a localized intermediate risk prostate cancer incidentally identified a PSMA-avid left supraspinatus lesion, which was subsequently biopsy-proven as a granular cell tumour. We present the first case of PSMA-avid granular cell tumour and add to the growing literature documenting PSMA-PET avidity in benign and malignant lesions apart from prostate cancer., Competing Interests: None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology.)

Oesophageal Granular Cell Tumour (GCT) is a rare tumour arising from schwann cells of the submucosal nerve plexus. They are slow-growing generally, benign though malignant potential has been reported. They are usually found incidentally during endoscopic evaluation of dyspepsia or dysphagia. They rarely produce symptoms on their own unless the size is larger, ulceration occur on their surface or when it compresses the adjacent structure. Though they are submucosal, they are usually diagnosed by standard biopsy techniques or after an endoscopic resection. Oesophageal GCTs without muscularis propria attachment are amenable for Endoscopic Submucosal Dissection (ESD) which is a minimally invasive procedure when compared to surgical resection. They may require follow-up after resection. Here, we report a case of 39-year-old male who presented with epigastric pain, heart burn and underwent endoscopy for the same, which revealed a sub-centimetric yellowish white flat lesion above oesophago-gastric junction. Biopsy was done and histopathology and immuno-histochemistry revealed sheets of tumour cells with clear granular cytoplasm which stained positive for S100 and Calretinin, with a Ki-67 index of 2%, confirming the diagnosis of a benign GCT. Endoscopic Ultrasound (EUS) revealed no local invasion and the patient was advised three months follow-up and annual surveillance endoscopy.

Granular cell tumours (GCTs) are a rare form of neoplasm found throughout the body. Tracheobronchial involvement is less common. We describe a case of tracheal GCT in a 37‐year‐old Japanese woman presenting with throat discomfort. A tracheal tumour was found during laryngoscopy for undefined throat discomfort. Bronchoscopy demonstrated a white sub‐epithelial solitary nodule on the tracheal wall, and pathological examination of the biopsy samples confirmed GCT. No therapeutic procedures were performed, and the tumour is currently under strict observation. Throat discomfort is a rare presentation of tracheal tumours, but an early inspection using laryngoscopy and bronchoscopy may be helpful in determining an accurate diagnosis.

Granular cell tumours (GCTs) are rare submucosal lesions, thought to develop from Schwann cells, characterised by large polygonal cells with abundant lysosomes. The objectives of this study are to investigate whether GCTs have an antigen-presenting cell (APC) phenotype or a neural crest phenotype using immunohistochemistry and to compare expression profiles with Schwannomas. Immunoreactivity to CD68, HLA-DR, CD163, CD40 and CD11c (APC phenotype) and markers of neural crest cell (NCC) origin S100, SOX10, NSE and GAP43 in 23 cases of GCTs and 10 cases of Schwannomas were evaluated. RT-qPCR was used to identify a possible NCC developmental phenotype in 6 cases of GCTs. GAP43 was identified as a new NCC marker for GCTs, and some evidence was found for an APC phenotype from CD68 and HLA-DR immunoreactivity. RT-qPCR failed to identify an NCC developmental phenotype of GCTs, likely due to technical issues.

Granular cell tumours are uncommon acquired benign tumours of nerve sheath origin that are usually seen in the head and neck region and upper aero-digestive tract. They usually present as solitary small sized nodules in middle age. The tumour is usually benign and composed of sheets of large sized cells with abundant granular cytoplasm containing lysosomal macro-inclusions known as pustulo-ovoid bodies of Milian (POB) that represent the heterogeneity of the lysosomes. No well-established criteria for malignancy have been described for this tumour. In this article, we have discussed a rare case of granular cell tumour of the penis with its characteristic histomorphology and immunohistochemistry and relevant differential diagnosis. [ABSTRACT FROM AUTHOR]

Objective: Pituicytomas and granular cell tumours (GCTs) of the neurohypophysis are considered non-adenomatous neoplasms in the sellar region. The association between hormone hypersecretion and the tumours is seldom discussed and unclear. Therefore, we attempt to investigate this association based on our experience and a review of the literature. Methods: We report three patients who presented with Cushing's syndrome- or acromegaly-like symptoms at our institution. They underwent transsphenoidal surgery for suspected pituitary adenomas, which were subsequently diagnosed as pituicytomas or hypophyseal GCTs following histological and immunohistochemical analysis. We also review previously reported relevant cases of pituitary non-adenomatous tumours in the literature. Results: Four cases of Cushing's syndrome with pituicytoma and one case of acromegaly with a GCT have recently been reported. In the three cases presented here, one patient with Cushing's syndrome and one patient with acromegaly also had a pituicytoma, while the second patient with acromegaly had a GCT. Conclusions: Rather than mere coexistence of non-adenomatous pituitary tumours with hypersecretory adenomas or hyperplasia, alternative causes for the observed symptoms maybe the presence of some unidentified substances produced by the tumours that stimulate the adenohypophysis to secrete pituitary hormones. The glial cells of the pituitary gland may play an important role in oncogenic differentiation and regulation of the release of hormones. Therefore, attention should be focused on investigating the origin and functions of glial cells. [ABSTRACT FROM AUTHOR]

Objective: Granular cell tumour (GCT) is a benign neoplasm that originates from Schwann cells. Within the oral cavity, it usually appears as a lingual nodule and especially amongst female adults. Histologically, GCT shows a proliferation of polygonal cells with eosinophilic granular cytoplasm, which can be associated with a pseudoepitheliomatous hyperplasia (PEH). In this study, we analyse the main clinicopathological data of intraoral GCT and we compare our results with previous studies. Material and Methods: We have studied a series of 56 cases of oral GCT in Spain and Brazil, and we have conducted a systematic review in PubMed, Web of Knowledge and Scopus databases, using the keywords: "granular cell tumour" and oral. Results: In our series, GCT appeared as an asymptomatic benign tumour that is more frequent in women and in the tongue. PEH was observed in 32% of the lesions. In the review, we collected 282 cases of oral GCT with a similar clinical profile; seven patients had multiple lesions, and 33% of the cases presented PEH. No cases of malignant oral GCT have been described to date. GCT is an uncommon oral benign neoplasm, mainly unique and asymptomatic, derived from Schwann cells. Conclusions: Although the etiopathogenesis of this oral tumour is unknown, its characteristics suggest that it could have a reactive nature. Conducting a complete clinicopathological study in all intraoral GCT is fundamental in order to dismiss other entities, including oral carcinoma. [ABSTRACT FROM AUTHOR]

A 21-year-old female California kingsnake (Lampropeltis californiae) was presented to the University of Veterinary Medicine, Vienna, Austria, with a space-occupying mass in the caudal abdomen. Following clinical, radiological and sonographical evaluation the mass was removed surgically. Histopathology and transmission electron microscopy confirmed the diagnosis of a granular cell tumour, but immunohistochemical labelling for a range of markers was negative. This lesion is rare in mammals and birds, but has not been reported previously in a reptile. [ABSTRACT FROM AUTHOR]

Granular cell tumours (GCTs) are uncommon neoplasms mostly reported in man, dogs and horses. The origin of GCT is thought to be Schwann cells, with the associated characteristics of neural crest morphology. Neoplastic cells often demonstrate positive immunoreactivity for S100, LC3, vimentin and p62. They are also periodic acid–Schiff (PAS) positive and diastase resistant. A female green tree python (Morelia viridis) was presented for severe constipation and hyporexia of 4 month's duration and, despite treatment, died the next day. A 4.8 × 3.4 mm intracalvarial GCT was identified, compressing the overlying cerebrum without invasion. Neoplastic cells were immunoreactive to S100 and had brightly eosinophilic cytoplasmic granules that were PAS positive and diastase resistant. Electron microscopy revealed numerous cytoplasmic lysosomes in neoplastic cells. GCTs are reported rarely in non-mammalian species with three reports in birds. This represents the first report of a GCT in a reptile. [ABSTRACT FROM AUTHOR]

Morphological overlap exists between cutaneous granular cell tumours (GCT) and malignant melanoma, with the melanocyte-specific markers HMB45 and Melan-A commonly used to support the diagnosis of melanoma. We recently encountered several cases of GCT in our practice showing strong expression of Melan-A. The aim of this study was to establish the prevalence of positive immunohistochemical staining for Melan-A and HMB45 in a series of unequivocal GCTs. We also aimed to assess the prevalence of staining for PRAME (PReferentially expressed Antigen in MElanoma), a marker expressed in >80% of primary melanomas as well as many non-melanocytic tumours. A total of 20 cutaneous/subcutaneous GCTs were evaluated using Melan-A, HMB45 and PRAME immunohistochemistry. Staining for Melan-A and HMB45 was scored using a semiquantitative scale from 0 (absent) to 3+ (staining present in >50% of tumour cells). PRAME expression was recorded as either positive (>75% of cell nuclei staining) or negative. Melan-A expression was observed in four GCTs (20%), with strong and diffuse (3+) staining seen in two cases (10%), both from anogenital areas. Weak patchy nuclear PRAME expression was seen in every case, interpreted to be negative. HMB45 was also negative in all cases (100%). Our study demonstrates that Melan-A expression can be strong and diffuse in a subset of otherwise unequivocal cutaneous GCTs, which may cause diagnostic confusion with malignant melanoma. HMB45 and PRAME did not stain any of the GCTs in our series., (Copyright © 2023 Royal College of Pathologists of Australasia. All rights reserved.)

Testicular neoplasms are reported rarely in pet and laboratory rabbits (Oryctolagus cuniculi f. dom.), with interstitial cell tumours being the most commonly described testicular neoplasm. In this retrospective study, paraffin wax-embedded testicles with neoplastic changes from 52 rabbits were investigated. Five out of 52 animals exhibited more than one tumour type, resulting in a total of 57 tumours. Granular cell tumours were the most prevalent neoplasm with 36 examples (63%) out of the 57 testicular tumours. Interstitial cell tumours, Sertoli cell tumours and seminomas occurred less frequently. Granular cell tumours of the testis are rare in rabbits. Histological similarities between granular cell and interstitial cell (Leydig cell) tumours in haematoxylin and eosin-stained tissue sections may lead to misdiagnoses. The periodic acid–Schiff reaction or immunohistochemistry for periaxin and S100 protein, as well as ultrastructural analysis, are useful methods to confirm the diagnosis. [ABSTRACT FROM AUTHOR]

The case of a 5-year-old intact female Pitbull Terrier with a granular cell tumour (GCT) of the mammary gland is presented. The dog was admitted for surgical removal of a non-painful lump assumed to be a fibroadenoma. Histological and immunohistochemical findings leading to the diagnosis consisted of polygonal tumour cells with well-defined cell borders and granular cytoplasm, staining positively with neuron-specific enolase (NSE) and protein S100 and negatively for cytokeratin AE1-AE3. Some important points in the diagnostic and therapeutic approach to this uncommon neoplasm are discussed. To our best knowledge this is the first case of such tumour in the mammary gland described in the veterinary literature. [ABSTRACT FROM AUTHOR]

Dermatofibroma-like granular cell tumour (GCT) is a rare entity, with only two cases having been described so far. We report another case in a 62-year-old woman, discuss histopathological features, and review other tumours in which granular changes have been observed. Our tumour was composed predominantly of oval-to-spindle granular cells with prominent nucleoli, arranged in short fascicles and storiform pattern, infiltrating around collagen bundles. Immunohistochemical analysis with antibodies against CD31, CD56, CD68, CD117, S-100 protein, inhibin, calretinin, EMA, p53 and MIB-1 was performed, showing expression of CD56, CD68, S-100 protein, inhibin and calretinin. The diagnosis of atypical dermatofibroma-like GCT was made.

Granular cell tumour is an uncommon benign soft tissue neoplasm of controversial origin arising virtually at any body site, including the orofacial region. Clinically, oral granular cell tumour appears as a solitary, pink or yellowish coloured, sessile, asymptomatic nodule of less than 2 cm in diameter. Approximately 10% to 20% of patients may present multiple lesions. Microscopically, it consists of proliferation of large polygonal, oval or bipolar cells with abundant, fine or coarsely granular cytoplasm and a small, pale-staining or vesicular nucleus eccentrically located in the cell. Upto 2% of granular cell tumours behave aggressively and may how metastasis. About 2% lesions show malignant behaviour. Here we report a solitary granular cell tumour on the dorsum of tongue with clinical, histopathological, and immunohistochemical details. [ABSTRACT FROM AUTHOR]

Granular cell tumour is a rare soft tissue tumour of Schwann cell origin. This is usually solitary and benign but rarely can be multiple and malignant. Most commonly involved sites are tongue, skin and subcutaneous tissue but can occur at any site. Clinically, it can be misdiagnosed as dermal appendageal tumour or soft tissue tumour. Definitive diagnosis is made by histopathological examination demonstrating sheets of large polygonal or round, granular cells which are positive for S-100 on immunohistochemistry. Excisional biopsy is done as both diagnostic and curative purpose. Regular follow up is needed to look for recurrence and malignant transformation. Here we document a case of benign GCT in a 45 yrs old female.

Purpose: To analyse the antigen expression profiles of 27 cases of pituicytoma, spindle cell oncocytoma, and granular cell tumour of the sellar region concerning a common pituicytic origin of neoplastic cells. Methods: Material from 12 female and 15 male patients (13 granular cell tumours of the sellar region, 10 pituicytomas, four spindle cell oncocytomas) collected in the German Registry of Pituitary Tumours between 1993 and 2015 was re-evaluated according to the current WHO classification of tumours of the central nervous system and supplementary immunohistochemistry including S100-protein, CD56, CD68, thyroid transcription factor-1 (TTF-1), and Ki-67 was performed. Results: S100-protein was detected in all 27 tumours and TTF-1 in all 16 tumours that were assessed. Vimentin was expressed in all 13 cases investigated whereas broad spectrum cytokeratin was not detected in any of 14 evaluated cases. GFAP was observed in nine out of 21 cases. 15 out of 17 investigated lesions showed some CD68 expression and five out of 14 cases were labelled with CD56 antibodies. Proliferative activity did not differ significantly between the three tumour subgroups although one primary and one recurrent pituicytoma showed exceptionally high Ki-67-proliferation indices of 15.3 and 12.7 %, respectively (means: granular cell tumour of the sellar region 2.0 %, pituicytoma 2.8 %, spindle cell oncocytoma 2.7 %). Conclusions: The study confirms and expands earlier data and is in line with the notion that the three tumour types are variants of pituicytoma. [ABSTRACT FROM AUTHOR]