Squamous cell carcinoma rarely occurs in the ureter and accounts for less than 1 percent of all renal neoplasm. It is usually associated with chronic inflammation, such as infection, urolithiasis, or other irritations.  

Herein, we report a case of a 65-year-old man, who complained of hematuria and right flank pain for 2 weeks and Computed Tomography scan (CT) scan performed at outside hospital disclosed an intraluminal soft tissue in right upper ureter, leading to upstream hydronephrosis. There was no distant metastases or regional lymphadenopathy.

        The patient came to our hospital for further management. There was no past history of systemic disease and lab data showed no anemia (Hb 15.5 g/dL), normal renal function (Creatinine 0.94 mg/dL). Diagnostic uretero-renoscopy revealed a non-papillary broad-based tumor at right upper ureter and we then proceeded right robotic-assisted radical nephroureterectomy and bladder cuff excision. The pathology revealed pT2 ureter squamous cell carcinoma and pT2 renal pelvis urothelial carcinoma with surgical margin free of tumor. The pathology report of ureter SCC was confirmed by pathologist and  excluding the diagnosis of urothelial carcinoma with squamous differentiation. The patient had no tumor local recurrence, metastasis or bladder recurrence at first 3-month post-operative follow up with CT scan, cystoscopy and urine cytology.

Discussion

        Concurrent upper urinary tract UC (UTUC) and SCC is rare and there is no standard of care protocol of treatment currently. However, radical surgery even for metastatic site is a treatment choice. However, both adjuvant Cisplatin-based chemotherapy or immune checkpoint inhibitor maybe considered for pT3, pT4, or lymph node positive UTUC after surgery based on the current evidence (POUT trial and CheckMate 274 trial). The mainstay treatment for squamous cell carcinoma is surgery and adjuvant systemic therapy (chemotherapy or target therapy such as EGFR inhibitors) is considered for metastatic disease or lymph node invasion. Holmang et al, reported that the average post-operative median overall survival is 7 months for SCC versus 50 months for conventional UC. The risk factors for ureteral squamous cell carcinoma include: chronic infections, renal or ureteral calculi, vitamin A deficiency, radiotherapy or other damage that could lead to squamous metaplasia to squamous cell. In our case, none of the risk factors were found. After well discussion at our multidisciplinary tumor boards (MDT), regular  close follow up is recommended for this patient.

Conclusion

        Back to our cases, the patient had achieved no evidence disease at 3 months FU after surgery to date. However, close follow up is warranted for the disease possess poorer oncological outcomes. Surgery is the mainstay of treatment and adjuvant therapy may be considered for locally advanced disease. For patients with risk factors for squamous cell carcinoma, early detection and diagnosis is important and the radical surgical resection should be arranged if the patient’s condition allowed.