Serum Protein Patterns in Participants With Mycosis Fungoides/Cutaneous T-Cell Lymphoma, Psoriasis, or Normal Skin

DISEASE CHARACTERISTICS: * Meets criteria for 1 of the following categories: * Healthy skin volunteer * No significant inflammatory or neoplastic disease of the skin or internal organs * Diagnosis of 1 of the following skin diseases\*: * Psoriasis * Plaque-type disease * Psoriasis Area and Severity Index score at least 12 * Mycosis fungoides/cutaneous T-cell lymphoma * Clinical diagnosis of T1-T4 skin disease with a compatible pathologic diagnosis NOTE: \*Stable or worsening disease on no therapy or topical therapy only within the past 2 weeks PATIENT CHARACTERISTICS: Age * 18 to 85 Performance status * Not specified Life expectancy * Not specified Hematopoietic * Not specified Hepatic * Not specified Renal * Not specified Other * Not pregnant * No known HIV-1-related diseases * No known HTLV-1-related diseases * Willing to undergo brief skin examination and fill out a questionnaire regarding skin and general health PRIOR CONCURRENT THERAPY: Biologic therapy * Not specified Chemotherapy * Not specified Endocrine therapy * Not specified Radiotherapy * Not specified Surgery * Not specified Other * More than 2 weeks since prior systemic therapy for skin disease