Comparative analysis of PD-L1 expression and tumor-infiltrating lymphocytes in metaplastic breast carcinoma and gynecologic carcinosarcoma: A single-institution retrospective study.

Metaplastic breast carcinoma (MBC) and gynecologic carcinosarcoma (GCS) are rare, clinically aggressive cancers that demonstrate epithelial components and mesenchymal or sarcomatoid components. In this study, we assessed PD-L1 expression and tumor-infiltrating lymphocytes (TILs) in MBC and GCS. Overall, PD-L1 positivity using the SP142 clone was seen in 50 % of MBC and 51.9 % of GCS cases, with PD-L1 expression in tumor cells significantly higher in MBC cases (p = 0.034), and PD-L1 expression in immune cells similar in MBC and GCS cases. PD-L1 expression was significantly higher in epithelial components than in mesenchymal components in both MBC and GCS cases (p = 0.0005). TILs were low in the majority of MBC and GCS cases (≥ 10 %) and generally correlated with PD-L1 expression; however, many PD-L1 positive cases with low TILs were seen. PD-L1 expression using the 22C3 clone was additionally assessed, with positivity seen in 62.9 % of MBC cases and 30 % of GCS cases. Concordance between SP142 and 22C3 results was seen in 62.5 % of MBC cases and 80 % of GCS cases. Overall, our findings suggest that a subset of MBC and GCS cases may benefit from immune checkpoint inhibitor therapy. Our findings also illustrate unique aspects of PD-L1 expression patterns in these tumors which may harbor additional prognostic and therapeutic significance.

Defective DNA Mismatch Repair Influences Expression of Endometrial Carcinoma Biomarkers.

Endometrial endometrioid carcinomas are related to estrogen excess and express estrogen and progesterone receptors. However, hormone receptor expression can be variable from tumor to tumor, and this variability is not always explained by differences in tumor grade. Variable expression of other biomarkers that may be used in the diagnostic work-up of endometrial cancer has also been noted. We hypothesized that mismatch repair (MMR) defects may contribute to this variability. A total of 411 unselected endometrial carcinomas were evaluated for immunohistochemical expression of DNA MMR proteins and MLH1 methylation. Loss of immunohistochemical expression of MLH1, MSH2, MSH6, or PMS2 was defined as MMR deficient; positive expression was defined as MMR intact. A case-control cohort of 80 Grade 2 endometrioid carcinomas was selected from this set (40 MMR deficient, 40 MMR intact). Cases were matched for histotype, grade, and age. Estrogen receptor, progesterone receptor, CK7(+), CK20, and Pax-8 immunohistochemistry was evaluated. The median percentage of CK7 tumor cells was significantly lower in the MMR deficient group compared with the MMR intact group. The mean percentage of tumor cells exhibiting estrogen receptor expression was similar in both the MMR-deficient and MMR intact groups. However, there was greater variability in the MMR-deficient group. Our study shows that MMR defects influence the expression of clinically important biomarkers for endometrioid-type endometrial carcinoma as decreased cytokeratin 7 expression is more commonly associated with MMR deficiency.

Adaptive Radiation Therapy for Intact Thymoma: An Illustrative Report.

BACKGROUND/AIM: Adaptive radiation therapy (ART) is a technique capable of reducing radiation dose to normal tissue without compromising local control. For potentially resectable thymoma, induction therapy is standard of care. Because large disease volume is common in this context, ART has been suggested to reduce toxicity from induction chemoradiation. This has not been previously illustrated in the literature. CASE REPORT: A 38-year-old man with initially unresectable thymoma was treated with induction chemoradiation including cisplatin and etoposide. He received 45 Gy in 25 fractions and ART was utilized to shrink the radiotherapy field for the final 10 fractions. RESULTS: Thymectomy showed Masaoka stage III disease with negative margins. He experienced no treatment-related toxicity and has no evidence of disease 8 years after diagnosis. CONCLUSION: Induction chemoradiotherapy with ART appears to be feasible, safe, and efficacious for locally advanced intact thymoma.

Uterus Septus Subtotalis Bicollis: A Rare Mullerian Duct Abnormality.

Mullerian duct anomalies (MDAs) are congenital defects of the female genital system that arise from abnormal embryological development of the Mullerian ducts. Septate uterus is the most common, resulting from incomplete resorption of the medial septum after fusion of the Mullerian ducts. Two main types of septate uterus exist, including septa that extend completely or partially from the uterine fundus to the cervical os. The combination of a uterine septum with a double cervix has been previously described; however, in most cases the septum was complete. We present a case of a 23-year-old female with a partial uterine septum and a double cervix. We refer to this atypical MDA as "uterus septus subtotalis bicollis". The description, characterization, and diagnosis of rare MDAs is important as they imply distinct therapeutic modalities.