Radiotherapy suitable for most primary cutaneous B-cell lymphomas

January 2, 2008

NEW YORK (Reuters Health) - Radiotherapy is appropriate for most patients with primary cutaneous B-cell lymphomas (CBCL), according to a recent Dutch study, but more aggressive treatment is needed in patients presenting with lesions on the leg.

The study, published in the December issue of the Archives of Dermatology, was a 20-year retrospective analysis using the recent World Health Organization (WHO)-European Organization for Research and Treatment of Cancer (EORTC) consensus classification for primary cutaneous lymphomas.

This classification recognizes three main types of CBCL: two indolent types -- primary cutaneous marginal zone lymphoma (PCMZL) and primary cutaneous follicle center lymphoma (PCFCL) -- and the more aggressive primary cutaneous large B-cell lymphoma, leg type (PCLBCL, LT).

Dr. Nancy J. Senff, of Leiden University Medical Center, and colleagues evaluated the effects of radiotherapy (median dose 40 Gy, range 20-46 Gy) in 153 patients treated with curative intent between 1985 and 2005.

Of the 25 patients with PCMZL, most presented with lesions on the trunk or arms. Radiotherapy resulted in complete remission in all 25, although 15 experienced a relapse after a median of 16 months. Overall, patients with PCMZL had an excellent prognosis, with a 5-year overall survival of 90% and a 5-year disease-specific survival of 95%.

Of the 101 patients with PCFCL, most presented with solitary or localized lesions; 8 had lesions on one or both legs. Radiotherapy resulted in complete remission in all 101, although relapse was noted in 29 after a median of 12 months. The 5-year overall survival was 90%, and the 5-year disease-specific survival was 97%.

The 27 patients with PCLBCL were considerably older on average; 25 of them presented with lesions on the legs. Radiotherapy resulted in complete remission in 25 (93%) of these patients. Ultimately, 10 showed extracutaneous dissemination, and 11 died of lymphoma. For all 27, the 5-year overall survival was 40% and the 5-year disease-specific survival was 59%.

"Subgroup analysis," the researchers write, "showed that patients presenting with skin lesions on the leg more often had relapses, more often developed extracutaneous disease, and had a much more unfavorable prognosis than did patients presenting with skin lesions on the head or trunk."

This confirms other recent studies, they say, and suggests that such cases should not be treated routinely with radiotherapy.

Dr. Senff told Reuters Health that the WHO-EORTC classification assists with retrospective analyses like the one her group did, since patient groups and treatment results can be more consistently compared. She added that "clinicians will benefit from this uniform classification system, in the sense that they will be provided with more uniform treatment guidelines."