[Role of radiotherapy in the treatment of multiple myeloma]

Chemotherapy is the treatment of choice in multiple myeloma; but there are no curative options. Therefore, the treatment rationale is characterized by reduction of symptoms and inhibition of complications. Regarding reduction of pain, treatment of (impending) fractures, and spinal cord compression radiation is an important part of palliative treatment. In our retrospective study we report the effect of radiotherapy on reduction of pain, recalcification and the reduction of neurological symptoms and evaluate factors which have an impact on therapeutic outcome.

From 1, Jan 1988 to 31, Dec 1998, 42 patients (19 women, 23 men; range of ages 46 to 85 years, median age 64.9 years) with 71 target volumes were irradiated (median dose 36 Gy, 2 to 3 Gy 5 times/week) because of symptomatic disease (67/71: osseous pain, 45/71: fractures/impending fractures, 13/71: spinal cord compression) (Tables 1 and 2). The median time from diagnosis to the first course of radiotherapy was 11.9 months (0.3 to 90 months). At the time of first irradiation, 5 and 37 patients were in tumor Stage II and III (Salmon/Durie), respectively. The median value of the Karnofsky performance was 70% (40 to 90%).

During follow-up (at least 6 months) in 85% of target volumes complete and partial pain relief (measured by patients' perception and the use of analgetic medication) was achieved; recurrences were seen in 8.8%. In 26/56 (46.4%) lesions evaluable a recalcification was seen whereas 17.9% showed progressive disease (comparison of radiographs before and after radiation). In 22.3% of all lesions initially with impending fracture (4/18) radiotherapy failed because of fracture after treatment (Tables 3 and 4). Simultaneous chemotherapy and a Karnofsky performance > or = 70 had a significant impact on a positive response to treatment, respectively. Spinal cord compression symptoms were reduced in 7/13 (53.8%) of patients (scaled due to the classification by Findlay 1987). The median survival from diagnosis for the entire group was 34.9 months (7.5 to 119.3 months), after irradiation 13.1 months (0.2 to 105.3 months) (Figure 1).

When adequately indicated radiotherapy has shown to be an effective palliative treatment. Taking under consideration that the results are retrospective we suppose that in multiple myeloma the local response to radiation is supported by a favorable performance status and simultaneous chemotherapy. Irradiation treatment does not change prognosis regarding overall survival.