Risk Associated with Severe Hematological Toxicity in Patients with Urothelial Cancer Receiving Combination Chemotherapy of Gemcitabine and Cisplatin.

Introduction: Combination chemotherapy of gemcitabine and cisplatin (GC) is the standard treatment for patients with urothelial cancer (UC). However, hematological toxicity is a major side effect of GC therapy in patients with UC. In particular, discontinuation of the GC therapy is associated to adverse events such as hematological toxicity. Some studies have reported general risk factors of hematological toxicity such as age. However, little is known about risk factors for GC therapy-associated hematological toxicity in patients with UC.

Objective: We aimed to identify risk factors for hematological toxicity in patients with UC receiving GC therapy.

Methods: We performed a retrospective evaluation of the data of 128 patients with UC who received GC therapy. The study end point was defined as the occurrence of grade 4 neutropenia and grade ≥3 thrombocytopenia. Logistic regression analysis was used to determine risk factors that were significantly associated with neutropenia and thrombocytopenia.

Results: In total, 62 (48.4%) patients experienced grade 4 neutropenia, and 27 (21.1%) patients experienced grade ≥3 thrombocytopenia. In the multivariate analysis, performance status (PS) ≥1 (odds ratio [OR] 3.764, 95% confidence interval [CI] 1.410-10.047, p = 0.008) and neutrophil count (OR 0.648, 95% CI 0.468-0.898, p = 0.009) were significantly associated with grade 4 neutropenia. Platelet count (PLT) (OR 0.896, 95% CI 0.832-0.966, p = 0.004) and potassium (K) level (OR 6.966, 95% CI 1.313-36.989, p = 0.023) were also significantly associated with grade ≥3 thrombocytopenia.

Conclusions: PS ≥ 1, neutrophil count, PLT, and K level were important risk factors for GC therapy-induced hematological toxicity in patients with UC. To continue GC therapy, further management systems by hematological toxicity risk factors for patients with UC will be required.