Metastatic Clear Cell Adenocarcinoma of the Urethra in a Male Patient: Report of a Case

Clear cell adenocarcinoma of the male urethra: a case report

Background

Primary urethral cancer in males is rare. Clear cell adenocarcinoma is more rare. We report a case in an African male suspected to have a urethral stricture.

Case presentation

A 66-year-old man presented in with preceding intermittent haematuria and acute urinary retention. Failed attempts at catheterisation necessitating a suprapubic catheter insertion raised the suspicion of a urethral stricture. Multiple irregular urethral filling defects were seen on a retrograde urethrogram. Urethroscopy revealed obstructing urethral masses. Histology reported clear cell adenocarcinoma.

Conclusion

Primary urethral cancer should be entertained as a differential diagnosis of a urethral stricture in a patient with haematuria, difficult urethral catheterisation and ambiguous urethrogram findings. Cystoscopy and biopsy are essential in the investigative work-up to make the distinction.

Primary clear cell adenocarcinoma of female urinary tract: a case report and literature review

Background

Primary clear cell adenocarcinoma of the urethra is extremely rare, reported only in single case reports, and its histological origin is not clear. There is no standard treatment for CCAU at present, and surgery is still the main treatment for CCAU without distant metastasis.

Case presentation

A 67-year-old female complained of gross hematuria with frequent micturition and urgency. No urethral diverticulum was found by cystoscopy or MRI, and the mass grew around the urethra. Urethral and anterior pelvic viscera resection was performed. Clear cell adenocarcinoma was confirmed by immunohistochemistry after the operation, and no recurrence or metastasis was found after one year of follow-up.

Conclusion

CCAU is very rare, and most cases originate from the urethral diverticulum and some may also originate from tissues around the urethra. For CCAU patients without distant metastasis, the main treatment is still surgery, and radiotherapy and chemotherapy can be performed for patients with distant metastasis. Gene detection may provide guidance for the precise chemotherapy of CCAU.

Comprehensive genomic profiling of histologic subtypes of urethral carcinomas

BACKGROUND

Carcinoma of the urethra (UrthCa) is an uncommon Genitourinary (GU) malignancy that can progress to advanced metastatic disease.

METHODS

One hundred twenty-seven metastatic UrthCa underwent hybrid capture-based comprehensive genomic profiling to evaluate all classes of genomic alterations (GA). Tumor mutational burden was determined on up to 1.1 Mbp of sequenced DNA, and microsatellite instability was determined on 114 loci. PD-L1 expression was determined by IHC (Dako 22C3).

RESULTS

Forty-nine (39%) urothelial (UrthUC), 31 (24%) squamous (UrthSCC), 24 (19%) adenocarcinomas NOS (UrthAC), and 12 (9%) clear cell (UrthCC) were evaluated. UrthUC and UrthSCC are more common in men; UrthAC and UrthCC are more common in women. Ages were similar in all 4 groups. GA in PIK3CA were the most frequent potentially targetable GA; mTOR pathway GA in PTEN were also identified. GA in other potentially targetable genes were also identified including ERBB2 (6% in UrthUC, 3% in UrthSCC, and 12% in UrthAC), FGFR1-3 (3% in UrthSCC), BRAF (3% in UrthAC), PTCH1 (8% in UrthCC), and MET (8% in UrthCC). Possibly reflecting their higher GA/tumor status, potential for immunotherapy benefit associated with higher tumor mutational burden and PD-L1 staining levels were seen in UrthUC and UrthSCC compared to UrthAC and UrthCC. Microsatellite instability high status was absent throughout.

CONCLUSIONS

Comprehensive genomic profiling reveals GA that may be predictive of both targeted and immunotherapy benefit in patients with advanced UrthCa and that could potentially be used in future adjuvant, neoadjuvant, and metastatic disease trials.