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The omasum is the third forestomach compartment of pecoran ruminants. It is assumed that the re-absorption of fluid present in the forestomach digesta (that facilitates particle sorting, digestion, and harvest of microbes) is its main function, so that less diluted digesta is submitted to enzymatic digestion in the lower digestive tract. Here, we evaluate measures of omasum size (representing 84 ruminant species in the largest data set) against body mass and proxies of the natural diet (%grass) or forestomach physiology (fluid throughput), using phylogenetically controlled models. The origin of specimens (free-ranging or captive) did not have an effect in the data set. Models with the best support invariably either included %grass or a physiology proxy in addition to body mass. These effects were not necessarily additive (affecting the intercept of the allometric regression), but often indicated a change in the allometric body mass-exponent with diet or physiology. Only models that allowed an influence on the allometric exponent yielded basic exponents compatible with predictions derived from geometry. Species that include more grass in their natural diet, or that have a "cattle-type" physiology marked by a high forestomach fluid throughput, generally have larger omasa. However, the existence of outliers, as well as the overall data pattern, suggest that this is not an obligatory morphophysiological condition. Circumstantial evidence is presented leading to the hypothesis that the comparatively small and less complex omasa of "moose-type" species do not necessarily represent an "original" state, but may be derived from more complex states by ontogenetic reduction and fusion of omasal laminae., (© 2019 Wiley Periodicals, Inc.)

The histologic findings of five patients with clinically typical Bowenoid dysplasia (BD) allowed the authors to classify the vulvar and perineal biopsies of 18 patients under 40 years as BD and the vulvar biopsies of six patients under 40 years as squamous cell carcinoma in situ (CIS). The two best criteria for BD are cellular uniformity and absence of pilosebaceous involvement. Vesicular chromatin is a less constant feature of BD. Clinically, patients with BD were younger than those with CIS, more frequently had elevated and multiple lesions and other developed BD with pregnancy. Histologic features therefore discriminate between clinical BD and CIS, but the authors emphasize that both clinical and pathologic features are necessary for proper diagnosis. Follow-up of BD has been benign, with one exception. Spontaneous regression occasionally occurred. One patient with CIS developed microinvasive carcinoma. Patients with BD were regarded at lesser risk for invasive carcinoma than patients with CIS; they are therefore amenable to conservative therapy.

A randomized clinical trial was conducted in women with bulky (suboptimal) Stage III and Stage IV ovarian carcinoma, using doxorubicin (Adriamycin) and cyclophosphamide with or without cisplatin. There were 440 evaluable cases, of which 227 had measurable disease. One hundred twenty of these latter patients were treated with cyclophosphamide and doxorubicin (CA), while 107 received cyclophosphamide, doxorubicin and cisplatin (CAP). The clinical complete response (CR) rate for CA was 26% (31/120) compared with 51% (55/107) for CAP (P = less than 0.0001). Of 23 CRs receiving CA who had a second-look laparotomy, only four were negative; of 39 CRs receiving CAP and a second-look, 13 were negative (not statistically significant). The response duration for patients with measurable disease (median 14.6 versus 8.8 months), progression-free interval for all patients (13.1 versus 7.7 months), and survival for patients with measurable disease (19.7 versus 15.7 months) showed a statistically significant advantage for CAP; however, there was no difference in survival of patients with nonmeasurable disease. Toxicity was more severe with CAP but was tolerable. Thus, the addition of cisplatin improves the chemotherapy of advanced ovarian carcinoma.

We have encountered three cases of a recently recognized form of granulosa cell tumor referred to by Scully as the juvenile type, and we have made ultrastructural observations on one case. This variant is encountered almost exclusively in the first two decades, and is characterized at the optical microscopic level by a macrofollicular or a diffuse, sometime disorderly pattern of growth, often with extensive luteinization and hyperchromatic nuclei. One of our patients developed precocious pseudopuberty. Our ultrastructural observations in this case supported the concept that this tumor is a granulosa cell tumor, and the tumor showed some similarities to previously reported granulosa cell tumors. A spectrum of cells was observed ranging from well differentiated granulosa cells to stromal cells with many intermediate forms present. The stromal cells varied from being fibroblast-like to theca-like. Both granulosa and stromal cells sometimes contained abundant lipid. Evidence of luteinization, i.e. abundant smooth endoplasmic reticulum and tubular mitochondrial cristae, was not noted in either the granulosa or stromal cells. Focal areas of smooth endoplasmic reticulum were found, however, in teh cytoplasm of cells intermediate between granulosa and stromal types. These cells may represent the source of steroid hormone secretion.

The relationship between steroid receptor content and response of metastatic breast cancers to endocrine therapy and cytotoxic chemotherapy has been examined. In 54 advanced breast cancers treated with hormonal therapy, 20 of 29 (69%) ER+, PR+ and 3 of 14 (21%) ER+, PR- tumors responded. Of the nine tumors that lacked both ER and PR, 2 (22%) were hormonally responsive. Based on either the ER or PR content alone, 68% of the PR+ and 54% of the ER+ tumors responded to endocrine therapy. Thus, the addition of PR assay could improve the accuracy of ER assay in selecting a hormonally responsive breast cancer. In 29 advanced breast cancers treated with cytotoxic drugs, the presence of ER and/or PR in the tumors seemed to favor an objective response to cytotoxic chemotherapy. The response rate was about 67% regardless of whether the cancers were ER+ or PR+.

The clinicopathologic findings of 13 patients having extramammary Paget's disease of the vulva are discussed with emphasis on its histogenesis and biological behavior. For the purpose of study and assessment of prognosis, these cases were divided into two groups, those with an underlying invasive cutaneous adnexal adenocarcinoma, and those lacking an underlying invasive lesion. Four cases contained invasive cutaneous adnexal adenocarcinoma; in one of these the invasion was superficial. Three of the cases with an invasive lesion and three other cases showed in situ adenocarcinoma of sweat glands. Surgical treatment is mandatory for both groups of patients. The prognosis was excellent for the patients having Paget's disease without an underlying invasive carcinoma. From the literature, the prognosis of those with an underlying invasive carcinoma of the vulva appears to be less favorable. Multiple surgical excisions may be required to control the recurrences and metastases. A frequent association with other internal malignancy was observed. In four cases, second malignancies were found. Of special interest was the demonstration in one case of columns of neoplastic cells extending from involved sweat glands to the surface epithelium via the intradermal sweat duct. Our study leads us to support the concept that the Paget's cells, in a number of cases, are derived from an underlying carcinoma in situ of sweat gland origin.