Marsden S. Blois

The frequency of local recurrence and microsatellites as a guide to reexcision margins for cutaneous malignant melanoma.

A retrospective study was undertaken of local, regional, and distant recurrences in 346 patients with primary melanomas of tumor thickness less than 1.0 mm that were excised with margins of normal skin varying between 0.1 cm and 5.0 cm or more. Prospective histopathologic examination of 284 melanomas for the presence of microsatellites was also performed and their effect upon the frequency of local recurrence was studied. Margins of excision did not influence the frequency of local, regional, or distant metastases. Four recurrences of in situ superficial spreading melanoma occurred, however, when very narrow margins of excision (0.5 cm or less) were employed. Microsatellites were uncommon with tumors less than 3.0 mm in thickness (2.8% of all tumors of less than 3.0 mm in thickness, taken together), but relatively frequent in association with thicker tumors (37%). Melanomas with microsatellites were associated with a greater frequency of local clinical metastasis than those without (14% vs. 3%). Removal of more than 1.0 cm of normal skin around a melanoma of less than 1.0 mm in thickness does not further reduce rates of recurrence of any type. The use of margins of 0.5 cm or less for melanomas with a radial growth phase does appear to result in an increased frequency of local recurrence of the primary melanoma with an epidermal in situ component. These recurrences can be prevented by the removal of 1.0 cm of normal skin around such a melanoma. Microsatellites constitute a risk factor for local recurrence, but are a relatively uncommon phenomenon at tumor thickness less than 3.0 mm.

Regression in malignant melanoma. A histologic feature without independent prognostic significance

A total of 844 cutaneous malignant melanomas were examined prospectively for the presence or absence of histologic regression within the primary tumor. Cases were then stratified into three groups according to tumor thickness and survival was compared between substrata with and without regression in each group. The distribution of other major prognostic variables within these substrata was assessed and their influence as potential confounding variables considered. No statistically significant effect of regression on survival was found in any of the three thickness strata. These results do not confirm the finding of an earlier study, which suggested that regression may be a poor prognostic sign when found in association with thin malignant melanomas. Regression was almost invariably associated with the radial growth phase of melanomas. Regression was more common in male than in female patients, and was more frequent in association with truncal than extremity or head and neck melanomas.

Factors related to patient delay in seeking medical attention for cutaneous malignant melanoma

This study investigated the relationship between patient delay in seeking medical attention and prognostic indicators, tumor characteristics, and demographic and behavioral factors in 106 patients with cutaneous malignant melanoma. Patients with less readily apparent lesions, particularly on the back, had longer delays in seeking treatment, as might be expected. The prognostically unfavorable nodular melanomas were detected more frequently by patients themselves than they were found during visits to physicians for unrelated problems. In terms of behavioral variables, patients with less knowledge of melanoma or its appropriate treatment had significantly longer delays. Patients who minimized the seriousness of their condition were more likely to seek treatment sooner, perhaps because this reduced fear and anxiety about the disease or its treatment. For superficial spreading melanoma, delay was significantly and positively correlated with Clarks level of invasion, and also with tumor thickness when only noncoincidentally diagnosed patients were included; whereas for the nodular type, delay was significantly and positively associated with tuomr thickness, whether the patient was coincidentally diagnosed or not. The significance of these findings for early detection, and hence improved prognosis of malignant melanoma, is discussed.

The Melanins: Their Synthesis and Structure

Although the melanins are among the most widely distributed and visible of the biological pigments, the understanding of their synthesis, structure, and function has been a story so prolonged as to constitute a case study in the history of biology. From the early commentary by Aristotle (315 b.c.), to the most recent investigations, the study of melanins has involved virtually every applicable chemical and physical technique, and the motivation in this research has reflected the biological fashions of each era. Notwithstanding these efforts, we still do not know their chemical structures or molecular weights, their mode of. synthesis is not yet agreed upon, a satisfactory nomenclature remains to be devised, and even their biological roles are more a matter of surmise than proof.

Frequency and duration of patient follow-up after treatment of a primary malignant melanoma

To develop guidelines for the follow-up of patients with primary cutaneous melanoma (clinical Stage I), we studied 295 patients who had presented with a primary melanoma and who subsequently developed evidence of metastatic disease in the course of follow-up. Cox multivariate analysis was used to assess the influence of five variables in predicting the interval of time from the diagnosis of melanoma to the first clinical or laboratory evidence of metastatic disease (disease-free interval). The variables studied were tumor thickness, patient sex, patient age, elective lymph node dissection, and primary tumor location. Tumor thickness was found to be the major predictor of disease-free interval, which shortened progressively with increasing tumor thickness. Men had a shorter mean disease-free interval than women, although this effect did not reach statistical significance at the 0.05 level. Patient age, tumor location, and elective lymph node dissection were found not to be predictors of disease-free interval. The risk of recurrence of melanoma was tabulated, by year, for four intervals of tumor thickness. The increase in risk of recurrence associated with increases in tumor thickness above 1.5 mm was shown to occur predominantly in the early years following diagnosis-particularly in the first year. On the basis of our findings, we have suggested regimens of follow-up for melanoma.

Evaluating RECONSIDER: a computer program for diagnostic prompting

RECONSIDER, a computer program designed to perform as a diagnostic prompting aid, was evaluated for its ability to include the correct diagnosis in an ordered computed list of candidate diseases. The study was performed using 100 consecutive first admissions to the medical service of a university hospital, where the individuals entering the data into the program were blind to all but a limited set of findings known at time of admission. Each person entering the data created one or more lists of diagnostic possibilities (versions) using the program. The program suggested the correct diagnosis within the first 40 on its list 61% (498/797) of the time; the correct diagnosis was present with the first 40 in at least one version 93% (98/105) of the time. Performance was found to be best with cases having a single diagnosis and when more terms were entered into the program.

Judging prognosis in malignant melanoma of the skin. A problem of inference over small data sets.

Data was generated for 828 clinical stage 1 melanoma patients, divided into groups according to sex, tumor location, and tumor level for each of the 56 groups. Summary data, including the number of patients, number of patients dying as a result of melanoma, range of tumor thickness, mean and median tumor thickness, and mean length of follow-up of the surviving patients, are shown. Patients with melanoma of the palms and soles, subungual melanomas, and mucosal melanomas were excluded. A physician with a new melanoma patient could select the appropriate group for his or her patient, matched with respect to sex, location, and level, and then make a judgment regarding the prognosis, based on the survival experience of the group. In a few groups, the small numbers of patients provides only a rough impression of survival, but with many groups, a fair estimate can be made. The effectiveness of elective lymph node dissection was examined by creating 111 pairs of patients, matched by sex, level, location, and tumor thickness (to within — 12%), in which one member of the pair had an elective node dissection (ELND) and the other did not. There was no statistically significant difference between the survival of the two groups.

WORD AND OBJECT IN DISEASE DESCRIPTIONS

Experiments were conducted on a book, Current Medical Information and Terminolog~, (AMA, Chicago, 1971, edited by Burgess Gordon, M.D.), which is a compendium of 3262 diseases, each of which is defined by a collection of attributes. The original purpose of the book was to introduce a standard nomenclature of disease names, and the attributes are organized in conventional medical form: a definition consists of a brief description of the relevant symptoms, signs, laboratory findings, and the like. Each disease is, in addition, assigned to one (or at most two) of eleven disease categories which enumerate physiological systems (skin, respiratory, cardiovascular, etc.). While the editorial style of the book is highly telegraphic, with many attributes being expressed as single words, it is nevertheless easily readable (see Figure i).