Objectives: To study the long-term results of treatment of patients with generalized patch and/or plaque mycosis fungoides and to identify clinical characteristics predictive of survival and response to treatment.
Design: A single-center, 35.5-year retrospective cohort analysis.
Setting: Private referral medical center.
Patients: One hundred seventy-six patients with generalized patch and/or plaque (T2) mycosis fungoides.
Main outcome measures: Long-term actuarial survival and freedom-from-relapse results as calculated by the Kaplan-Meier method.
Results: The long-term (35.5-year) survival of patients with T2 mycosis fungoides is worse than the expected survival of a race-, age-, and sex-matched control population (P<.001). The median survival of the T2 group is 11.7 years. Patients younger than 58 years (median age) at presentation have a more favorable overall and disease-specific survival than the patients who are 58 years or older (P<.001 vs P<.025). Patient sex or race had no significant effect on overall survival. Patients who presented with palpable clinically significant lymph nodes (stage IIA) had long-term survival results similar to those without lymphadenopathy (stage IB), despite improved freedom-from-relapse outcome for patients with stage IB. Twenty-four percent of patients who progressed to more advanced disease had a lower complete response rate to initial therapy than did other patients (21% vs 65%) (P<.001). Patients who received total skin electron beam therapy had a better complete response rate than patients treated with topical mechlorethamine hydrochloride alone; the relapse-free results were superior in patients with a total dose of 30 Gy or higher and in patients who received topical mechlorethamine as adjuvant therapy following total skin electron beam therapy. Despite differences in freedom-from-relapse results among different treatment groups, long-term overall or disease-specific survivals were not significantly different.
Conclusions: A significant proportion (24%) of patients with generalized patch and/or plaque (T2) mycosis fungoides experience disease progression to a more advanced clinical stage, and nearly 20% eventually die of the disease. Younger patients have a more favorable disease-specific long-term outcome than patients who are older. Presence of lymphadenopathy (stage IIA) at diagnosis does not predict worse long-term survival outcome. Clinical features predictive of disease progression include initial lymphadenopathy (stage IIA) and lack of complete response to initial treatment. Despite superior complete response rate to a 30-Gy or higher dose of total skin electron beam therapy, topical mechlorethamine proves to be a cost-effective initial treatment for patients with T2 disease. The concept of an adjuvant therapy after irradiation is appealing, although it may not lead to improved long-term survival.