Modern Day Oncology for a Rare Pathology: Treatment Course of Rare Basaloid Non-Keratinizing Urethral Carcinoma

Purpose: Primary urethral carcinoma (PUC) is a rare neoplastic process in the United States with an annual incidence estimated at 4.3 per million in men and 1.5 per million in women. PUC is broken into three subtypes; transitional, squamous cell carcinoma (SCC), and adenocarcinoma. Basaloid non-keratinizing SCC further represents a rare subtype of urethral SCC. Advances in systemic management with immunotherapy in conjunction with more targeted radiation techniques have changed treatment and quality of life for those with metastatic disease.

Methodology: Here-in we describe the management of basaloid non-keratinizing SCC of the Urethra with progression to metastatic disease

Results: A 51-year-old female initially presented with hematuria and discomfort at the urethral meatus. A computed tomography (CT) urogram identified 3 x 3 cm urethral mass. Biopsy showed invasive nonkeratinizing HPV-mediated squamous cell carcinoma, (GATA3 + P16+ CK 5/6+ CK7+) validated at Memorial Sloan Kettering Cancer Center. She underwent surgical resection, however, 6 months later he was found to have left lower lobe metastasis and underwent lobectomy. PDL1 status was obtained and was positive in 90% of cells. She started atezolizumab immunotherapy, however, 3 years later she was found to have oligoprogressive disease with two enlarging nodules in the left lower lobe and right middle lobe. She received stereotactic body radiation therapy (SBRT) to the right middle lobe (54Gy in three fractions) complicated by lung pneumonitis. Her immunotherapy was discontinued due to pneumonitis. She then received SBRT (60Gy) to her lower lobe lesion. Over the next three and a half years she received several targeted palliative radiation treatments including SBRT to her left upper lobe (60Gy) 2 years following her initial lung radiation, 20Gy to symptomatic bilateral iliac and right scapular lesions 28 months from her initial radiation; stereotactic radiation treatment(SRT) to 5 new brain metastasis at 3 years from her initial radiation; stereotactic radiosurgery (24Gy) to a new left frontal lobe metastasis 39 months from initial radiation; retreatment to her right scapula and left hip with (8Gy) 41 months from initial radiation. She currently is receiving chemotherapy with stable disease, pain well managed with low-dose opioids, and only occasional blurriness of vision secondary to radionecrosis from her initial intracranial SRT

Conclusions: Basaloid SCC of the urethra represents a rare primary neoplasm with expected median life-expectancy for metastatic disease quoted at 2-years in the literature. Despite this our patient has still survived 6 years following diagnosis of metastatic disease maintaining good quality of life. Modern systemic options and radiation therapy can protect patient quality of life for an extended period of time with minimal toxicity

References: Gakis, G., Witjes, J. A., Comperat, E., Cowan, N. C., De Santis, M., Lebret, T., ... & Sherif, A. M. (2013). EAU guidelines on primary urethral carcinoma. European Urology, 64(5), 823-830.