Effect of variant histology presence and squamous differentiation on oncological results and patient’s survival after radical cystectomy

Objective: To evaluate the effect of variant histology on pathological and survival findings in patients undergoing radical cystectomy due to muscle invasive bladder cancer. Materials and methods: Data from 146 patients with radical cystectomy performed due to muscle-invasive urothelial carcinoma between January 2006 to November 2016 at our clinic were investigated. The preoperative and postoperative data of patients with variant histology were compared with nonvariant urothelial carcinoma patients. Then of patients with variant histology only those with squamous differentiation (SqD) were compared with nonvariant urothelial carcinoma patients in terms of preoperative, postoperative and survival data. Results: Of the 146 patients, 23 had carcinoma with variant histology. Of these, 17 had SqD, 4 had glandular differentiation, 1 patient had plasmocytoid variant and 1 patient had sarcomatoid variant. In patients with variant histology, postoperative T stage and upstaging was higher, with no difference observed in terms of overall and cancer-specific survival compared with nonvariant urothelial cancer patients. SqD patients were observed to have higher postoperative T stage compared to nonvariant urothelial cancer patients, with no significant difference observed in terms of survival. Conclusions: In cystectomy pathologies, patients with variant histology (especially SqD patients) were observed to have proportionally higher T stage compared to nonvariant urothelial carcinoma; however there were no significant differences for overall survival and cancer-specific survival