Splenectomy as Initial Therapy in Twenty-six Patients with Leukemic Reticuloendotheliosis (Hairy Cell Leukemia)¹

Twenty-six of 44 patients with leukemic reticuloendotheliosis, or hairy cell leukemia, underwent splenectomy as the first treatment of their disease from 1 to 72 months after the diagnosis was established. The median presplenectomy peripheral blood counts were: hematocrit, 32%; leukocytes, 2,600/cu mm; and platelets, 63,000/cu mm. One to 4 months postsplenectomy, the median counts were: hematocrit 35%; leukocytes, 5,500/cu mm; and platelets, 247,000/cu mm. Improvement of the blood counts was the main gain resulting from splenectomy in these patients. Forty-two % of the patients achieved a complete response, and 58% achieved a partial response. The median spleen weight at operation was 1200 g, with a range of 250 to 4450 g. Our data suggest that even the minimally enlarged spleens caused a significant amount of sequestration, which can be alleviated by splenectomy. Thirteen patients had presplenectomy infections; three were acutely ill. Splenectomy was performed on these three patients as an emergency operation after failure of conservative therapeutic measures. All three improved and were discharged within 2 weeks. Nine patients had episodes of infection after splenectomy. Five patients died of hairy cell leukemia at a median time of 9 months after splenectomy; four of these had concurrent overwhelming infections as well. The actuarial survival rate for all 26 patients at 5 years was 72%; for complete responders the rate was 86%, and for partial responders the rate was 47%.

Splenectomy is the first treatment for patients with hairy cell leukemia when counts drop significantly (hematocrit, <25%; granulocytes, <500/cu mm; platelets, <50,000/cu mm) or when repeated infections occur. Eliminating the sequestering organ improves the peripheral blood counts. In spite of splenectomy and improved counts, however, a few patients have progressive disease. It is necessary to identify this subgroup of patients as soon as possible after splenectomy, inasmuch as therapy with single-agent alkylating drugs has been found to be effective.