Background: The diagnosis of second malignancies in patients with multiple myeloma is uncommon. It is debatable whether this tumor is in itself a risk factor for the incidence of second malignancies. Etiopathogenic factors which might account for this association were analyzed.
Materials and methods: Retrospective analysis of a series of 210 patients with myeloma controlled by a Medical Oncology Department from 1984 to 1998. After searching for the diagnosis of a second malignancy, thirteen patients were identified with both diagnoses. A descriptive statistical study was elaborated as well as an analysis of survival.
Results: There were seven males and six females, with a mean age at diagnosis of 69 years (57-80). The Durie-Salmon stages at diagnosis were: I-A (3), I-B (1), II-A (4), III-A (4). Associated solid malignancies included: hepatocarcinoma (2), prostate adenocarcinoma (2), soft tissue sarcoma (2), lung adenocarcinoma (1), cholangiocarcinoma (1), breast carcinoma (1), endometrial carcinoma (2) and bladder carcinoma (1). At diagnosis, seven of the solid malignancies were metastatic. At the time of this analysis, eleven patients had died, eight because of progression of the solid cancer, two because of progression of myeloma and one because of therapy toxicity. Two patients are still alive with stability of the myeloma and solid malignancy controlled after surgical resection.
Conclusions: The association was observed in 6.2% of patients with myeloma and occurs at an advanced age. IgG myelomas and in early stages predominated. Solid malignancies were diagnosed in advanced stages in most cases. A short term high mortality rate was observed due to progression of the solid malignancy. The frequency of the association did not seem to be higher than the overall incidence of second malignancies in patients with cancer.