Actinomycotic Endometritis.

Seven cases of actinomycotic endometritis were identified among 28,906 endometrial biopsies performed in the last 10 yr. The patients' ages ranged from 44 to 85 yr old. An intrauterine device was in place from 7 to 44 yr. The reasons to perform the biopsies included abnormal uterine bleeding, malodor, prolapse, pelvic inflammatory disease, and suspicion of metastatic uterine sarcoma. Definitive identification of Actinomyces israelii by culture was obtained in 1 case only. Gram, Gomori methenamine silver, and Fite stains were useful in the differential diagnosis with pseudoactinomycotic granules, Nocardia, fungi, and other bacteria. The Actinomyces-like organisms were surrounded by extensive suppurative reaction in all cases. The tissues showed florid neutrophilic and plasmacytic inflammation. The treatment consisted of intrauterine device removal and 10 to 30 d of antibiotics in 4 patients. The Actinomyces-like organisms persisted for 6 wk in spite of antibiotic therapy when the intrauterine device removal was delayed in one of those cases. Two patients had hysterectomy and salpingo-oophorectomy due to tubo-ovarian abscess and hysterectomy, salpingo-oophorectomy, and rectosigmoid excision due to pelvic abscess and septic emboli, both followed by 30 to 45 d of antibiotic therapy. One patient had hysterectomy not followed by antibiotics due to prolapse. No other pelvic abscesses were identified on follow-up, which ranged from 4 to 101 mo (median, 20 mo; mean, 44 mo).

Comparison of proliferation indices in glioblastoma multiforme by whole tissue section vs tissue microarray.

Tissue microarrays (TMAs) reduce the amount of tissue analyzed with the assumption that protein and gene expression patterns are homogeneous throughout tumors. Many tumor types, including glioblastoma multiforme (GBM), are heterogeneous in many regards, including cell proliferation. We retrospectively compared Ki-67 labeling indices (LIs) determined by whole tissue section (WTS) vs TMA in a series of 50 GBMs from 45 patients. A paired t test indicated that the difference between average LIs obtained from a TMA vs a WTS was not significant (P = .51). There was no correlation between TMA and WTS (r = 0.042; P = .77), indicating that the methods yielded very different results in individual tumors. The Ki-67 LI did not always correlate with the tissue section in an individual tumor; however, when evaluating a large number of tumors on a TMA, the LI range and mean LI were roughly comparable with the LI range and mean LI determined from the WTS.

Immunohistochemical overexpression of p16 and p53 in uterine serous carcinoma and ovarian high-grade serous carcinoma.

The immunohistochemical expression pattern of p16 in biopsy samples has been useful as part of a panel to distinguish adenocarcinomas arising from the endometrium from those arising from the endocervix. However, no information is available on the expression of p16 in uterine serous carcinoma (USC) or ovarian high-grade serous carcinoma that could be used for diagnostic purposes. Here, we retrospectively analyzed the immunohistochemical expression of p16 in 11 cases of USC (5 pure and 6 mixed with endometrioid adenocarcinoma) and 10 cases of ovarian high-grade serous carcinoma and compared p16 expression with that of p53 in the same samples. p16 was strongly expressed by 100% of tumor cells in all 11 uterine specimens and in 5 of the 10 ovarian specimens; of the other 5 ovarian specimens, 4 showed strong positivity in 20% to 80% of tumor cells, and 1 case showed only weak expression. Positivity for p53 was strong and diffuse (100% of tumor cells) in 5 uterine tumors and in 3 ovarian tumors. p53 expression in 6 of the uterine specimens and 7 of the ovarian specimens was present in fewer tumor cells, of weak intensity, or both. We also performed human papilloma virus (HPV) DNA in situ hybridization in 4 uterine pure serous carcinomas; all 4 were negative. The negative results were confirmed by reverse transcriptase in situ polymerase chain reaction. We conclude that p16, owing to its diffuse expression in USC, should not be interpreted as indicating cervical origin or HPV-induced carcinogenesis; however, p16 may be a better marker (albeit unspecific) than p53 for identifying USC. The overexpression of p16 in USC is unrelated to HPV. Further studies are necessary to determine whether p16 expression is useful in the differential diagnosis of ovarian high-grade serous carcinoma.