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Purpose This study aims to determine the pre-biopsy diffusion-weighted imaging (DWI) and magnetic resonance spectroscopic imaging (MRSI) characteristics of patients with high-grade prostatic intraepithelial neoplasia (HGPIN) and perform follow-up studies in these patients to assess the clinical implications. Materials and methods One hundred sixteen men with prostate specific antigen between 4 and 10 ng/ml underwent pre-biopsy MR examinations. Nine of them had HGPIN lesions without concomitant prostate cancer (PCa) on biopsy. Apparent diffusion coefficient (ADC) and metabolite ratio [Citrate/(Choline + Creatine)] were calculated and these 9 patients were followed to determine the clinical outcomes. Results Mean ADC for HGPIN foci was 1.01 ± 0.16 × 10 − 3 mm 2 /s while for the normal peripheral zone it was 1.69 ± 0.25 × 10 − 3 mm 2 /s (p < 0.005). Mean metabolite ratio for voxels in the HGPIN region of initial biopsy was 0.24 ± 0.16 while for the normal peripheral zone the value was 2.66 ± 1.57 (p < 0.005). Four of 5 patients who were available for follow-up were detected to have prostate cancer on repeat biopsy. No significant change in metabolite ratio and PSA was observed while ADC showed further reduction on follow-up. Conclusion HGPIN foci have ADC and metabolite ratio values similar to adenocarcinoma prostate, indicating that such patients have a high likelihood of developing cancer. DWI may help identify such men who may be candidates for close follow-up. [ABSTRACT FROM AUTHOR]

Abstract: Results of the preliminary study on the evaluation of the role of magnetization transfer imaging (MTI) of prostate in men who had raised prostate-specific antigen (PSA) (>4 ng/ml) or abnormal digital rectal examination (DRE) are reported. MT ratio (MTR) was calculated for 20 patients from the hyper- (normal) and hypo-intense regions (area suspicious of malignancy as seen on T2-weighted MRI) of the peripheral zone (PZ) and the central gland (CG) at 1.5 T. In addition, MTR was calculated for three healthy controls. Mean MTR was also calculated for the whole of the PZ (including hyper- and hypo-intense area) in all patients. Out of 20 patients, biopsy revealed malignancy in 12 patients. Mean MTR value (8.29±3.49) for the whole of the PZ of patients who were positive for malignancy on biopsy was statically higher than that observed for patients who were negative for malignancy (6.18±3.15). The mean MTR for the whole of the PZ of controls was 6.18±1.63 and is similar to that of patients who were negative for malignancy. Furthermore, for patients who showed hyper- (normal portion) and hypo-intense (region suspicious of malignancy) regions of the PZ, the MTR was statistically significantly different. These preliminary results reveal the potential role of MT imaging in the evaluation of prostate cancer. [Copyright &y& Elsevier]

Abstract: Proton magnetic resonance spectroscopic imaging (MRSI) and diffusion-weighted imaging (DWI) were carried out in men with increased prostate-specific antigen (PSA) level. Forty subjects [controls (Group I) and patients (Groups II and III with PSA >20 and 4–20 ng/ml, respectively)] were investigated using endorectal coil at 1.5 T prior to transrectal ultrasound (TRUS)-guided biopsy. Metabolite ratio [citrate/(choline+creatine)] and apparent diffusion coefficient (ADC) were calculated for identical voxels. In patients, voxels that showed lower metabolite ratio showed reduced ADC in the peripheral zone (PZ) of the prostate, and voxels with increased metabolite ratio showed higher ADC. Metabolite ratios were used to predict areas of malignancy if the ratio was <1.4 and if ADC value was <1.17×10−3 mm2/s. Patients in Group II had lower metabolite ratio and ADC in the PZ compared to controls and Group III. All 13 were positive for malignancy in MR, while 12 of 13 were positive on TRUS-guided sextant biopsy. In Group III, certain voxels of PZ that showed reduced metabolite ratio also showed lower ADC. A positive correlation was observed between metabolite ratio and ADC. MR predicted areas of malignancy in PZ in 15 of 20 patients; however, only six were positive on TRUS-guided biopsy perhaps due to high false-negative rate of TRUS-guided biopsy. Results show positive correlation between MRSI and DWI and their potential in detection of malignancy, thereby improving the diagnosis especially in patients with PSA level of 4–20 ng/ml. [Copyright &y& Elsevier]

Abstract: Focused pathological evaluation of axillary lymph nodes in breast cancer is gaining importance. Nuclear magnetic resonance (NMR) spectroscopy that assesses the whole of the specimen has the potential in evaluating micrometastases. The biochemical changes associated with breast cancer metastases in axillary nodes by in vitro NMR and its use in the detection of axillary metastases in a clinical setting in comparison with conventional histopathology is presented in this study. Eighty-eight lymph nodes obtained from 30 patients with breast cancer were investigated. Histopathology revealed metastases in 20 nodes from 11 patients, while in vitro NMR spectroscopy revealed metastases in 22 nodes. Out of these 22 nodes, 16 were the same, which showed metastases on histopathology, while 6 nodes have shown metastases only on in vitro magnetic resonance spectroscopy (MRS). These 6 nodes with suspicion of metastases on MRS were subjected to reevaluation with serial sectioning and immunohistochemistry, but no additional metastases were revealed. Forty metabolites could be identified from the MR spectrum of lymph nodes. The levels of the glycerophosphocholine-phosphocholine (GPC-PC), choline, lactate, alanine and uridine diphosphoglucose were elevated significantly in nodes with metastases. In addition, the intensity ratio of GPC-PC/threonine (Thr) was higher in nodes with metastases, and using this as marker, MRS detected the axillary metastases with a sensitivity, specificity and accuracy of 80%, 91% and 88%, respectively. Neoadjuvant chemotherapy (NACT) lowered the concentrations of GPC-PC and GPC-PC/Thr ratio. The accuracy of MRS in detecting metastases was 75% in patients who received NACT (n=9) as compared to 96% in those who did not (n=21). Our results demonstrate the potential of in vitro MRS in characterizing the metabolite profile of the axillary nodes with breast cancer metastases. It detected axillary metastases with reasonable accuracy and can be complementary to histopathological evaluation and immunohistochemistry. [Copyright &y& Elsevier]