[A Case of Renal Cell Carcinoma Recurrence in the Ureteral Stump, 8 Years after Radical Nephrectomy].

A 62-year-old woman underwent laparoscopic radial nephrectomy for the left renal cell carcinoma in September 2008. In July2016, the patient developed asymptomatic gross hematuria. Computed tomography (CT) revealed the enlargement of the left ureteral stump and an 11mm nodule in the superior lobe of the right lung. Since [F-18] fluoro-D-glucose-positron emission tomography-CT FDG PET-CT demonstrated a lung tumor, we decided to perform right upper lobectomybyvideo-assisted thoracoscopic surgeryin September. The patient was diagnosed with metastatic renal cell carcinoma. We then removed the left ureteral stump and performed partial cystectomy in November. A pathological examination revealed that the tumor was metastatic clear cell renal cell carcinoma invading the muscle layer. Two months later, the patient developed gross hematuria again. Cystoscopy revealed a 1cm tumor around the scar of partial cystectomy. Transurethral resection was performed, and a pathological examination revealed metastatic renal cell carcinoma. We herein report this case of renal cell carcinoma in which recurrence occurred in the ureteral stump, 8 years after radical nephrectomy.

Immunohistochemical CD73 expression status in gastrointestinal neuroendocrine neoplasms: A retrospective study of 136 patients.

The WHO 2010 classification divides gastrointestinal neuroendocrine neoplasms (GI-NENs) into neuroendocrine tumor (NET) G1, NET G2, neuroendocrine carcinoma (NEC) and mixed adenoendocrine carcinoma (MANEC) groups. A total of 136 cases of GI-NENs diagnosed at our hospitals as gastrointestinal carcinoids, endocrine cell carcinomas and NENs over the last 11 years, using the WHO 2010 classification were assessed. Among the 136 cases, 88.2% (120/136) were classified into the NET group (NET G1/G2) and 11.8% (16/136) were classified into the NEC group (NEC/MANEC). The incidences of lymphatic and venous invasions were higher in the NEC group compared with in the NET group (P<0.0001 and P=0.0021, respectively). The immunohistochemical staining of cluster of differentiation 73 (CD73) was evaluated in GI-NENs. CD73 is a potentially useful molecule in tumor immunity. In general, CD73 on the tumor cell membrane converts adenosine monophosphate to adenosine, which restrains the production of interferon-γ and cytocidal activity. Although the association between stem cells of pancreatic NENs and CD73 has been reported, few studies have reported on CD73 expression in GI-NENs. Immunohistochemical CD73 expression on the cytomembrane of neuroendocrine cells was detected in 27.2% (37/136) of the GI-NENs. The positive ratio of CD73 was significantly higher in the NEC group compared with in the NET group (P=0.0015). CD73 is also considered as a potential biomarker of anti-programmed death-1 (PD-1) therapy. The expression of programmed death-ligand 1 (PD-L1) on the cytomembrane of GI-NENs was assessed. The positive ratio of PD-L1 was higher in the NEC group compared with in the NET group (P=0.0011). Furthermore, CD73 expression status was significantly correlated with PD-L1 expression (P<0.0001). These results indicate that CD73 may be an interesting candidate for a biomarker for certain prognostic factors and therapeutics concerning PD-1 therapy.