Total skin electron beam therapy followed by adjuvant psoralen/ultraviolet-A light in the management of patients with T1 and T2 cutaneous T-cell lymphoma (mycosis fungoides)

Abstract

Purpose : Patients with mycosis fungoides [cutaneous T-cell lymphoma (CTCL)] may benefit from adjuvant therapy after completing total skin electron beam therapy (TSEBT). We report the results for T1 T2 CTCL patients treated with adjuvant oral psoralen plus ultraviolet light (PUVA) with respect to overall survival (OS), disease-free survival (DFS), salvage of recurrence, and toxicity. Methods and Materials : Between 1974 and 1993, TSEBT was administered to a total of 213 patients with CTCL. Records were reviewed retrospectively, and a total of 114 patients were identified as having T1 or T2 disease. Radiotherapy was provided via a 6-MeV linac to a total of 36 Gy, 1 Gy/day, 4 days/week, for 9 week. Beginning in 1988, patients were offered adjuvant PUVA within 2 months of completing TSEBT. This was started at 0.5-2 J/m 2, 1–2 treatments/week, with a taper over 3–6 months. Therapy then continued once per month. There were 39 T1 and 75 T2 patients. Six T1 (15%) and eight T2 (11%) patients were treated with adjuvant PUVA. A further 49% of the 113 patients received adjuvant systemic therapy, 3% received external beam, 4% received adjuvant ECP, 2% received topical nitrogen mustard, 22% received a combination of therapies exclusive of PUVA, and 9% received no adjuvant therapy. Patients were balanced in all subgroups based on pre-TSEBT therapy. The median age of the cohort was 58 (range 20–88), with a median follow-up time of 62 months (range 3–179). Results : Within a month after completing of TSEBT, 97% of T1, and 87% of T2 patients had achieved a complete remission. Stratified by adjuvant therapy, none of six T1 and one of eight T2 patients who received adjuvant PUVA failed within the first 3 years after completion of TSEBT. A total of 43% of the T1 and T2 patients receiving other or no adjuvant treatment failed within the same time course. The 5-year OS for the entire cohort was 85%. Those who received PUVA had a 5-year OS of 100% versus a 5-year OS for the non-PUVA group 82% ( p < 0.10). The 5-year DFS for the entire cohort was 53%. Those who received PUVA had a 5-year DFS of 85% versus a 5-year DFS for the non-PUVA group of 50% ( p < 0.02). By T stage, those with T1 receiving PUVA exhibited no relapses, whereas those with T1 not treated with PUVA had a crude relapse rate of 36%. Median DFS was not reached at 103 months for the T1 adjuvant PUVA patients versus 66 months for the non-PUVA patients p < 0.01). For those with T2, crude relapse rates were 25% and 55%, respectively, with DFS of 60 (median DFS not reached) and 20 months ( p < 0.03). The 5-year DFS for patients salvaged with PUVA was 50%. Toxicity of adjuvant and salvage PUVA therapy was acceptable, with only two patients requiring a reduction in PUVA dosage. Conclusion : PUVA can maintain remissions in patients with CTCL after TSEBT. There is a significant benefit in DFS but no statistically significant improvement in OS. Prospective, randomized data are needed to confirm these results. PUVA is also effecgive as a salvage therapy after TSEBT in early-stage patients with recurrence, with acceptale toxicity.