A simple clinical scoring system to improve the sensitivity and standardization of the diagnosis of mycosis fungoides type cutaneous T-cell lymphoma: logistic regression of clinical and laboratory data.

BACKGROUND: The diagnosis of mycosis fungoides (MF) is notoriously difficult to establish because in the early stages, histological features may be nonspecific or merely suggestive. OBJECTIVES: To standardize the diagnosis of MF. METHODS: We studied 138 patients with suspected MF referred over a 7-year period to a university department of a dermatology-based cutaneous lymphoma clinic. Six diagnostic criteria were evaluated: clinical morphology, clinical distribution, skin biopsy T-cell receptor gene rearrangement (TCR-GR), skin biopsy pan T-cell marker loss > or = 2, skin biopsy CD4/CD8 ratio > or = 6, and skin biopsy diffuse epidermal HLA-DR expression. These six clinical and laboratory criteria were compared by logistic regression analysis in patients with histologically diagnosed MF and those with benign disease. RESULTS: Of the 138 patients, 74 had histology of MF, 47 of benign dermatoses and 17 were indeterminate. Close associations were found between a histological diagnosis of MF and TCR-GR (odds ratio 14.4), classical morphology (7.5), classical distribution (2.5) and diffuse epidermal HLA-DR expression (2.8). Logistic regression models were developed depending on the availability of data (either TCR-GR or HLA-DR). Probabilities for correctly diagnosing MF compared with histology as the 'gold standard' were derived from these logistic regression models. A scoring system assigning point values based on these probabilities was then created in order to assist the clinician in making the diagnosis. If using TCR-GR data, a positive TCR-GR = 2.5 points, the presence of classical morphology = 2.0 points, and the presence of classical distribution = 1.5 points. A total score of > or = 3.5 points assigns a high probability (> 85%) of having MF. If using HLA-DR expression, then the presence of classical morphology = 2.5 points, a positive diffuse epidermal HLA-DR expression = 2.0 points, and the presence of classical distribution = 1.5 points. In this case, a total score of > or = 4.0 points assigns a high probability (> 85%) of MF. CONCLUSIONS: The logistic regression models and scoring systems integrate clinical and laboratory assessments, allow rapid probability estimation, and provide a threshold for the diagnosis of MF in an objective, standardized manner.

An ultrastructural comparison of mechanical dermabrasion and carbon dioxide laser resurfacing in the minipig model.

OBJECTIVE: To compare the histological and ultrastructural changes in skin collagen with mechanical dermabrasion and pulsed carbon dioxide laser resurfacing in the minipig model. SETTING: Academic medical center. SUBJECTS: Yucatan minipig animal skin model. MAIN OUTCOME MEASURES: Comparison of light microscopic and ultrastructural (electron microscopic) changes in the skin following the 2 resurfacing modalities. RESULTS: No significant difference in collagen histological characteristics or ultrastructure was detected between the 2 comparison groups. CONCLUSIONS: When mechanical dermabrasion or pulsed carbon dioxide laser resurfacing is used with similar-depth injury to the dermis in this model, the histological changes seen via light microscopy and ultrastructural changes seen via electron microscopy are similar between the 2 treatment modalities.

Use of chest radiography in the initial evaluation of patients with localized melanoma.

OBJECTIVE: To evaluate the use of an initial staging chest x-ray film in asymptomatic patients who present with localized primary cutaneous melanoma. DESIGN: The staging workup of 1032 consecutive asymptomatic patients with localized melanoma was retrospectively reviewed via database chart review. SETTING: Regional melanoma referral center in an academic medical center. PATIENTS: The melanoma database identified 1032 asymptomatic patients with localized melanoma for retrospective review. Of the patients studied, 876 (85%) of 1032 had an initial staging chest x-ray film performed. A chest x-ray film was considered initial if performed within 6 months of melanoma diagnosis. MAIN OUTCOME MEASURE: The rate of positive, negative, and suspicious findings of initial chest x-ray films. RESULTS: One hundred thirty (15%) of 876 patients had suspicious findings necessitating additional workup. Based on follow-up radiologic findings, only 1 (0.1%) of 876 had a true-positive chest x-ray film demonstrating pulmonary metastasis. CONCLUSIONS: The yield of detection of unsuspected pulmonary metastasis by chest x-ray film in the initial evaluation of asymptomatic patients with localized melanoma was exceedingly low (0.1%). Our results support the concept that routine chest radiograph screening in asymptomatic patients presenting with stage I and intermediate-thickness (1.5- to 4.0-mm) stage II melanoma is unlikely to yield true-positive findings of silent pulmonary metastasis. No definitive conclusions were drawn for the subset of patients with stage II thick melanoma (> 4.0 mm) because of the small number of patients (n = 40) in our series. Prospective studies are necessary to ultimately define the yield of initial radiographs in asymptomatic patients with localized melanoma.

Gene rearrangements and T-cell lymphomas.

BACKGROUND: Cutaneous T-cell lymphomas comprise a broad spectrum of neoplasia ranging from indolent to highly aggressive types. To determine subset lineage and malignant vs benign nature, morphologic analysis, immunophenotyping, and flow cytometry have been used. However, given the shortcomings of these methods, molecular genetic techniques, which take particular advantage of the clonal nature of malignancy, are now being applied to better characterize and diagnose these lymphomas. RESULTS: Each antigen-specific T cell and its clonal progeny has a unique rearrangement of its T-cell receptor gene such that it can recognize very specific antigenic epitopes. By visualizing these particular T-cell receptor gene rearrangements, Southern hybridization techniques and polymerase chain reaction amplification can detect clonal populations of T cells in the skin, blood, and lymph nodes of patients with T-cell leukemias and lymphomas. Clonal T-cell populations have also been found in cases of benign disorders such as lymphomatoid papulosis and pityriasis lichenoides et varioliformis acuta. Although these disorders usually have a benign outcome, they may represent dysplastic clonal lymphoid expansions with a high incidence of spontaneous regression. CONCLUSIONS: Molecular genetic techniques have added to our ability to diagnose, characterize, and monitor the course of T-cell lymphomas and leukemias. In addition, they may provide insight into the pathogenesis of certain benign disorders.