Background: Mycosis fungoides (MF) and Sezary syndrome (SS) are the most common forms of cutaneous T- cell lymphoma (CTCL). Various topical and systemic therapeutic alternatives are available, but there is no standard or definite curative treatment regimen. When making a decision about the appropriate treatment modality, the age and compliance of the patient, stage of the disease, treatment accessibility, and previous treatment history should be considered. Aim: To determine the therapeutic response of patients with MF and SS to different treatment modalities. Patients were evaluated with respect to their clinical and demographic features. Methods: One hundred and thirteen patients diagnosed clinically and dermatopathologically with MF and SS between March 1984 and June 2001 were included in the study. Results: Of the 113 patients studied, 110 had a diagnosis of MF and three had a diagnosis of SS; 101 patients (89.4% ) were diagnosed with early stage (IA, IB, IIA) and 12 (10.6% ) with late stage (IIB, III, IVA, IVB) disease. The age at diagnosis varied between 12 and 81 years (mean, 45.6 ± 15.8 years). Fifty- five (48.7% ) patients were male and 58 (51.3% ) were female. The duration of the skin lesions varied between 1.5 months and 32 years (mean, 6.1 years). Psoralen plus UVA (PUVA)was the most commonly used initial treatment modality in early stage disease (91% ), with a complete remission (CR)rate of 80.4% . With PUVA + interferon- α (INF- α ) treatment, CR was 57% in the early stages and 33.3% in the late stages. For late stage disease, systemic therapies, such as pentostatin, gemcitabine, and fludarabine, alone or in combination with INF- α , were preferred. Of the 113 patients, eight (7% of the total and 57.1% of the advanced stage cases) died of MF; 21.4% of the late stage patients showed partial remission and 14.2% showed CR. None of the patients diagnosed with early stage disease died of MF, but two (1.9% ) progressed to late stage disease. Conclusions: PUVA and PUVA + INF- α are effective treatment modalities, especially for early stage MF. Once the disease has progressed, both MF and SS are very resistant to treatment regimens, including chemotherapeutic agents. It is important to diagnose and treat these diseases, especially MF, in the early stages for lasting remission. Background: Mycosis fungoides (MF) and Sezary syndrome (SS) are the most common forms of cutaneous T-cell lymphoma (CTCL). Various topical and systemic therapeutic alternatives are available, but there is no standard or definite curative treatment regimen. a decision about the appropriate treatment modality, the age and compliance of the patient, stage of the disease, treatment accessibility, and previous treatment history should be considered. Aim: To determine the therapeutic response of patients with MF and SS to different treatment modalities. Patients were evaluated with respect to their clinical and demographic features. Methods: One hundred and thirteen patients diagnosed clinically and dermatopathologically with MF and SS between March 1984 and June 2001 were included in the study. Results: Of the 113 patients studied, 110 had a Of the patients diagnosed with MF and three had a diagnosis of SS; 101 patients (89.4%) were diagnosed with early stage (IA, IB, IIA) and 12 The age at diagnosis varied between 12 and 81 years (mean, 45.6 ± 15.8 years). Fifty-five (48.7%) patients were male and 58 (51.3%) were female Psoralen plus UVA (PUVA) was the most commonly used initial treatment modality in early stage disease (91%), with a complete remission (CR ) with a rate of 80.4%. With PUVA + interferon-α (INF- α) treatment, CR was 57% in the early stages and 33.3% in the late stages. For late stage disease, systemic therapies, such as pentostatin, gemcitabine, and Of the 113 patients, eight (7% of the total and 57.1% of the advanced stage cases) died of MF; 21.4% of the late stage patients showed partial remission and 14.2% showed CR. None of the patients diagnosed with early stage disease died of MF, but two (1.9%) progressed to late stage disease. Conclusions: PUVA and PUVA + INF- α are effective treatment modalities, especially for early stage MF. Once the disease has progressed, both MF and SS are very resistant to treatment regimens, including chemotherapeutic agents. It is important to diagnose and treat these diseases, especially MF, in the early stages for lasting remission.