Mature cystic teratoma (MCT) is the most common ovarian tumor. Secondary malignant tumors rarely arise in MCTs, and squamous cell carcinoma (SCC) is the most common form of such tumors. MCT-derived SCC in situ (CIS) is mostly found together with invasive SCC; it is seldom detected alone. A 44-year-old woman with breast cancer was found to have a left ovarian cyst (size > 8 cm) before treatment. She underwent bilateral salpingo-oophorectomy, and frozen biopsy showed MCT with focal proliferation of squamous epithelium and mild atypism. However, definitive pathologic diagnosis confirmed CIS arising in MCT. In addition, germline BRCA 1/2 test and human papillomavirus test of tumor tissue yielded negative results. This report is the first case of its kind in Korea. Our report can aid in clinical decision making and serve as a basis for follow-up studies on this rare type of CIS arising in MCT.
Adult ; Biopsy ; Breast Neoplasms ; Carcinoma in Situ ; Carcinoma, Squamous Cell* ; Clinical Decision-Making ; Diagnosis ; Epithelial Cells* ; Epithelium ; Female ; Follow-Up Studies ; Humans ; Korea ; Neoplasms, Germ Cell and Embryonal ; Ovarian Cysts ; Teratoma*

Purpose: We investigated whether the use of a phosphodiesterase-5 inhibitor (PDE5i) after robot assited radical prostatectomy has a survival benefit over non-use patients because there are controversial results on the association between PDE5i use and survival outcomes for prostate cancer patients in literature. Materials and Methods: We designed a retrospective, matched, large-sample cohort study of 5,545 patients who underwent robot assisted radical prostatectomy (RARP) during 2013–2021 in a single institute. The exclusion criteria was patients who were aged >70 years at surgery, American Society of Anesthesiologists (ASA) physical status classification grade 4 or 5, history of other malignancies, patients who started PDE5i 6 months after survery and patients with follow up period less than 24 months after surgery. Among the 1,843 included patients, 1,298 were PDE5i users, and 545 were PDE5i non-users. We performed propensity score matching (PSM) of PDE5i users (n=529) with non-users (n=529) by adjusting for the variables of age, Gleason grade group, pathological T stage, preoperative ASA physical status grade, and International Index of Erectile Function score. Results: There were no significant difference in patient characteristics according to PSM. Kaplan–Meier curve revealed the difference of overall survival for PDE5i users and non-users (clustered log-rank test p<0.05). In a stratified Cox regression analysis, PDE5i use after RARP was associated with improved overall survival and reduced risk of death (hazard ratio 0.43; confidence interval 0.24–0.79; p=0.007). The limitation of this study was that the indication for the prescription of PDE5i was not given. Conclusions PDE5i administration after RARP were associated with overall survival of patients with prostate cancer. A further randomized control trial may reveal whether routine use of PDE5i after prostatectomy can improve survival of prostate cancer patient.