Carbon‐ion radiotherapy for inoperable upper tract ureteral cancer

Aim This study aimed to report initial results of hypofractionated carbon‐ion radiotherapy (C‐ion RT) for inoperable upper tract ureteral cancer. Methods Retrospective chart review was performed for five consecutive patients with medically inoperable ureter cancer that was treated with radical C‐ion RT between December 2013 and December 2014. The median age of the patients was 80 years (range, 68–84 years). The reasons for inoperability were advanced age, post‐contralateral nephrectomy, alcoholic cirrhosis, both advanced age and contralateral renal function degeneracy, and pneumonia. The median size of tumor was 2.8 cm (range, 2.2–4.0 cm). Diagnostic imaging did not identify lymph node metastases or distant metastases in any case. All patients underwent C‐ion RT (52.8 Gy relative biological effectiveness; 12 fractions in 3 weeks). The clinical target volume encompassed the growth tumor volume with a 5‐mm margin bilaterally; there was a 40‐mm margin craniocaudally but the clinical target volume did not encompass the whole ureter. Results Within a median follow‐up time of 32.9 months (range, 24–36 months), two patients died and three remained alive. Neither local recurrence nor regional lymph node metastases were observed. Secondary bladder tumor was observed in four patients, and one patient had a liver metastasis. Grade 1 hematuria was observed in two patients, and Grade 3 pyelonephritis was observed in one patient as acute toxicity. Ureteral obstruction was observed in two patients. Conclusion C‐ion RT might be a useful treatment option for inoperable ureter cancer. This study aimed to report initial results of hypofractionated carbon‐ion radiotherapy (C‐ion RT) for inoperable upper tract ureteral cancer. Good local control was achieved with preservation of the ipsilateral kidney therefore C‐ion RT might be a useful treatment option for inoperable ureter cancer.