Hematologic effects of intravesicular thiotepa therapy for bladder carcinoma

Twenty-nine patients with bladder carcinoma treated with intravesical thiotepa administration were reviewed to assess hematologic toxicity. Ten of 25 consecutive patients had at least one episode of acute myelosuppression. Thrombocytopenia was the most common abnormality; anemia was uncommon. Acute suppression occurred most often within the first three months of therapy and was dose related. One of the 25 patients and four additional patients had chronic myelosuppression; all were male. They were older and had received more thiotepa over a longer period than those patients without chronic myelosuppression. Thrombocytopenia was again the most common abnormality. Anemia was nearly as frequent in this subpopulation and may herald chronic blood dyscrasia. One patient had refractory anemia with an excess of blast forms; another had smoldering leukemia. Acute and chronic forms of myelosuppression were not related. Thiotepa treatments should be limited to 90 mg/mo and protracted therapy avoided in elderly men.