[Double cancer in elderly patients with hematologic malignancies].

The occurrence of multiple malignancy was studied in 674 patients with hematologic malignancies who were admitted to this department during the past 10 years. Of the 674 patients, 205 were aged 65 years or older, and 56 (8.3%) had another cancer. The frequency of multiple malignancy was significantly higher in older patients than in younger patients: 44 (21.5%) vs. 12 (2.6%). The major hematologic conditions in patients with multiple malignancy were multiple myeloma, myelodysplastic syndromes, non-Hodgkin's lymphoma, and chronic myelogenous leukemia. The major sites of cancers other than hematological malignancies were the stomach, colon, breast, and esophagus. Many of the older patients had gastric cancer or colon cancer, and gastric cancer was common in the younger patients. The multiple malignant neoplasms were synchronous in as many as 20 of the 44 older patients. There was only one such case among the younger patients. Of the 56 patients, nine had received alkylating agents, and one has received etoposide. In brief, elderly patients with hematologic malignancies are likely to have multiple malignant neoplasms. If they are synchronous, the patient's prognosis may be adversely affected, because simultaneous management of multiple malignant neoplasms is not easy.