Incidental finding of extramammary Paget's disease during active surveillance for early‐stage prostate cancer in a prostate biopsy

Introduction Skin tissue contamination within transcutaneous visceral organ biopsies is seldom found. We encountered a rare case of extramammary Paget's disease incidentally diagnosed by prostate biopsy during active surveillance for prostate cancer. Case presentation A 71‐year‐old Japanese patient was diagnosed with prostate cancer, and active surveillance was selected. After 1 year, prostate biopsy was performed by a transperitoneal approach, and 16 biopsy cores were taken. One biopsy core contained skin tissue showing extramammary Paget's disease. Careful skin examination confirmed the presence of an extramammary Paget's disease lesion in the left perineum, and curative surgical resection was performed. Recurrence and metastasis did not occur after 6 months of follow‐up. Conclusion Although the perianal region is a common site of extramammary Paget's disease, early‐stage extramammary Paget's disease is often asymptomatic. Thus, during a transcutaneous biopsy, it is important to consider the appearance of the skin and the pathological features of migrating skin tissue

Potential role of UGT pharmacogenetics in cancer treatment and prevention: focus on tamoxifen

Tamoxifen (TAM) is a selective estrogen receptor modulator that is widely used in the prevention and treatment of estrogen receptor-positive (ER(+)) breast cancer. Its use has significantly contributed to a decline in breast cancer mortality, since breast cancer patients treated with TAM for 5 years exhibit a 30-50% reduction in both the rate of disease recurrence after 10 years of patient follow-up and occurrence of contralateral breast cancer. However, in patients treated with TAM there is substantial interindividual variability in the development of resistance to TAM therapy, and in the incidence of TAM-induced adverse events, including deep vein thrombosis, hot flashes, and the development of endometrial cancer. This article will focus on the UDP glucuronosyltransferases, a family of metabolizing enzymes that are responsible for the deactivation and clearance of TAM and TAM metabolites, and how interindividual differences in these enzymes may play a role in patient response to TAM