Case records of the Massachusetts General Hospital. Case 5-2011. A 65-year-old man with hematuria after treatment for prostate cancer

Primary urethral adenocarcinoma harbors recurrent KRAS and EGFR alterations

Primary urethral adenocarcinoma is an extremely rare malignancy with an unclear pathogenesis. Previously, we reported 4 brachytherapy-associated (BA) urethral mucinous adenocarcinomas that developed following treatment for prostate cancer. In the present study, we report one additional BA and 3 radiation-independent (RI) urethral adenocarcinomas. The aim of this study is to explore the molecular alterations and to compare the clinicopathologic features. RNA sequencing was performed on 5 tumors, and a next-generation sequencing (NGS)-based fusion assay was used to identify gene fusions in 6 tumors. Additionally, NGS-based targeted genomic DNA sequencing was employed to analyze one metastatic BA tumor and one metastatic RI tumor. The 8 patients had a mean age of 67 (range: 37-87) years, with one being female in the RI cohort. Cystoscopy revealed the following urethral findings: a papillary lesion (4/7), mass causing obstruction (1/7) and irregular friable tissue (2/7). Seven patients underwent urethrectomy with cystectomy/prostatectomy/hysterectomy. The mean tumor size was 3.4 cm (range: 1.5-6.5). Adenocarcinoma in situ was noted in 5 tumors. All 5 BA tumors originated from the prostatic urethra, with 4 showing mucinous morphology and one enteric morphology, and showed moderate to poor differentiation and tumor stages of pT2 (2/4), pT3 (1/3) and pT4 (1/4). Two patients developed metastasis, one at 3.3 and one at 4.2 years after diagnosis, and all patients were alive at a median follow-up of 4.5 (range: 2-14) years. In contrast, 3 RI tumors arose from bulbar, prostatic, or female mid/distal urethra, presenting as enteric, mucinous, and not otherwise specified (NOS) subtypes, with well to moderate differentiation and a tumor stage of pT4 (2/2). Two died of the disease, while one was alive without disease at a median follow-up of 4 (range: 2.2-14.5) years. All tumors were diffusely positive for CK20, CDX2 (7/7), and AMACR (3/3), and lacked nuclear β-catenin expression (5/5). Most expressed CK7 (5/7). KRAS mutations (p.Gly12Val and p.Gly13Asp) were observed in one BA mucinous tumor and one RI NOS tumor with the p.Gly13Asp mutation also detected in the metastatic RI tumor. The EGFR p.Ser784Phe mutation was detected in one RI enteric tumor. TP53 p.Val172Phe, CDKN2A p.Leu32_Leu37del, and amplifications of EGFR and MDM2, were identified in a metastatic BA enteric tumor. No fusion transcripts were identified. In conclusion, urethral adenocarcinoma harbors recurrent KRAS and EGFR alterations, independent of prior radiotherapy. RI tumors appear to be associated with a worse prognosis compared to BA tumors.

Mucinous adenocarcinoma of the prostatic urethra after brachytherapy for prostatic adenocarcinoma: a case series

Mucinous adenocarcinoma of the urethra is extremely rare, even more so in a setting of postradiation therapy, with only 3 cases reported up to date including the first case published by our group in 2011. In the present study, we included the long-term follow-up on our previously reported case and report 3 additional cases. This is the first case series to date of this rare disease entity. The aim of this study is to review the clinicopathologic features of mucinous adenocarcinoma of the prostatic urethra in patients after receiving brachytherapy for prostatic adenocarcinoma. We identified 4 patients with a mean age of 72 years, and a mean interval of 14.8 years from brachytherapy for prostate carcinoma (grade group 1). Patients presented with hematuria or urinary retention. A colonoscopy was performed in three-fourth of patients and was within normal limits. Three patients underwent cystoprostatectomy and 1 had a transurethral resection of the prostate. On gross examination, only tumor formed a 3.5 cm tan-gray, ulcerated, friable, and necrotic mass and 2 displayed either irregular red granular or thickened areas within the prostatic urethra. Abundant extracellular mucin pools dissecting the prostatic stroma were present in all tumors, with clusters of tumor cells floating in the mucin. The mucin pools were lined by pleomorphic pseudostratified columnar mucinous epithelium. Tumors were diffusely positive for CK20, CDX2 (4/4), and AMACR (2/2); they focally expressed CK7 (2/4), and lacked nuclear β-catenin expression (3/3). PSA, PSAP, NKX3.1, p63, and GATA3 were negative in the tumors tested. Among the 3 patients who underwent radical surgery, 2 had stage 2 tumors (confined to the prostatic urethra and prostate), and 1 had a stage 3 tumor, with seminal vesicle involvement. All 4 patients were alive without disease with a mean follow-up of 4.9 years. In conclusion, brachytherapy-associated mucinous adenocarcinoma of the prostatic urethra displays intestinal-type features as its non-radiation-related counterpart. It appears to lack a villous adenoma component, displays a different immunohistochemical profile with diffuse CK20 and CDX2 positivity, and is associated with lower stage and less aggressive behavior.

Penile gangrene due to calciphylaxis: a multidisciplinary approach to a complex clinical challenge

Penile calciphylaxis is a rare but clinically challenging condition to manage. While multiple treatment options have been proposed, the underlying evidence is anecdotal, and the overall prognosis remains extremely poor. We describe the case of a patient who underwent urgent debridement of a suspected gangrenous penile tip, who was intraoperatively found to have penile calciphylaxis. The necrosis progressed and the patient had a glans amputation. A non-healing wound developed, requiring reconstruction with two skin grafts using foreskin by the plastic and reconstructive surgical unit. The patient was commenced on sodium thiosulfate and his wound had completely healed 2 months following his last operation. We review the literature to determine the biochemical features, management options and outcomes in patients with penile calciphylaxis.