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T B Fitzpatrick

Publications and source records attributed to T B Fitzpatrick.

At least 37 records · Page 2Linked to original sources
PubMed1987

Risk factors for cutaneous melanoma. A practical method of recognizing predisposed individuals.

Cutaneous melanoma is rapidly becoming a potentially curable cancer if it is detected and properly treated in an early phase of development. Unlike other cancers, which are usually hidden from detection until they are relatively large or metastatic disease has occurred, cutaneous melanoma is readily detectable simply by examining the skin. Information is now available that will be useful in selecting individuals at greatest risk. The most important melanoma risk factors (in decreasing order of importance) for a given individual are as follows: a persistently changed or changing mole, adulthood, irregular varieties of pigmented lesions (including dysplastic moles and lentigo maligna), a congenital mole, Caucasian race, a previous cutaneous melanoma, a family history of cutaneous melanoma, immunosuppression, sun sensitivity, and excessive sun exposure. Selective screening and appropriate treatment of individuals who have these risk factors may reduce the morbidity and mortality of cutaneous melanoma.

Adult↗
PubMed1987

A comparison of the melanocyte response to narrow band UVA and UVB exposure in vivo.

The visible cutaneous pigmentary response to ultraviolet-A (UVA) is immediate and, following sufficient exposure, may persist, whereas ultraviolet-B (UVB)-induced pigmentation appears after a delay of several days. We compared the in vivo response of melanocytes to single and multiple exposures of narrow band UVA and UVB irradiation which produced visibly equal increases in pigmentation. Using a xenon-mercury source matched to a monochromator, human volunteers were exposed to 304 (+/- 5) and 365 (+/- 10) nm radiation. Biopsies were performed 1, 7, and 14 days after irradiation. For each biopsy, the number of melanocytes per square millimeter of epidermis was determined using L-3,4-dihydroxyphenylalanine (dopa)- and tyrosine-incubated split epidermal preparations. Vertical sections were also examined. At days 7 and 14, after both 304 and 365 nm radiation, melanocytes were more intensely dopa-positive than in unirradiated controls, and demonstrated enlarged perikarya and a greater number of enlarged dendrites. Following both 304 and 365 nm radiation the number of dopa-positive melanocytes was increased at days 7 and 14 by 44% and 58%, respectively. Tyrosine positivity, an indicator of enhanced tyrosinase activity and increased melanin formation, was absent in controls and at day 1, and became positive in all but one sample at day 7 and day 14. Therefore, one day after UVA exposure, visible pigmentation but not tyrosinase activity was increased. At day 7, the number of tyrosine-positive melanocytes approximately equaled the number of dopa-positive melanocytes. Although UVA and UVB induce different pigmentary responses, their effects on melanocyte number and function were indistinguishable.

Adult↗
PubMed1986

Ocular abnormalities associated with cutaneous melanoma and vitiligolike leukoderma.

Several varieties of ocular pathology are associated with acquired cutaneous hypomelanosis (leukoderma; vitiligo). Our current study was undertaken to investigate the relationship between ophthalmologic disorders and a specific depigmentary phenomenon, the vitiligolike leukoderma of cutaneous melanoma. Over the past 14 years, eight patients with cutaneous melanoma and widespread areas of hypopigmentation were identified at the Pigmented Lesion Clinic of the Massachusetts General Hospital. The seven patients who underwent ophthalmologic examination had pigment-related ocular abnormalities. Among these were inflammations of the uveal tract in three patients, heterochromia in two, halo nevi of the choroid in one, and hypopigmentation and/or atrophy of the retinal pigment epithelium or choroid in four. Our findings demonstrate that ocular disease may be a component in a syndrome consisting also of cutaneous melanoma and vitiligolike leukoderma and suggest the need for complete ophthalmologic examinations in patients with melanoma and leukoderma.

Adult↗
PubMed1986

Usefulness of retinoic acid in the treatment of melasma.

Melasma is a circumscribed brown macular hypermelanosis of the areas of the face and neck that are exposed to light. Clinical trials with various depigmenting formulations containing hydroquinone were conducted to determine the ideal concentration of hydroquinone, retinoic acid, and corticosteroids for the treatment of melasma. The compounds were tested with and without the concomitant use of topical sunscreen preparations. Based on the results of the trials and our earlier clinical experience, we conclude that treatment of melasma should involve the following: avoidance of sun exposure, constant use of broad-spectrum sunscreens, and topical application of a cream or lotion containing 2% hydroquinone and 0.05% to 0.1% retinoic acid (tretinoin). Patients should suspend use of oral contraceptives and other agents that promote skin pigmentation. The monobenzyl ether of hydroquinone should never be used in melasma therapy.

Administration, Topical↗
PubMed1985

Actinic degeneration in association with long-term use of PUVA.

To determine the extent of clinical actinic damage that occurred in association with exposure to oral methoxsalen photochemotherapy (PUVA), dermatologists at 16 university centers assessed the wrinkling, telangiectasia, and altered skin markings on the buttocks and the dorsa of the hands among 1380 patients treated with PUVA. These changes are similar to those seen in skin that is chronically exposed to sunlight. After more than 5 years of prospective study, patients with psoriasis exposed to PUVA showed a significant dose-dependent increase in the prevalence of clinical actinic degeneration of the skin of the buttocks (p less than .05, F-test). The prevalence of moderate or severe change among those patients exposed to high doses of PUVA (more than 160 treatments) was low (11%). The degree of increased clinical actinic degeneration noted on the dorsa of the hands was also significantly related to total exposure to PUVA (p less than .05, F-test). Our findings indicate that long-term PUVA exposure is associated with an increase in clinical actinic degeneration of the skin. However, the magnitude of this increase is small and, after more than 5 years, is of limited clinical consequence to most patients.

Adult↗
PubMed1985

An evaluation of the effectiveness of azelaic acid as a depigmenting and chemotherapeutic agent.

In the past five years, it has been reported that certain dicarboxylic acids (C8-C13) and azelaic acid (C9) (AZA), in particular, have a remarkable effect in the management of lentigo maligna, human malignant melanoma, and certain disorders of hyperpigmentation. Preclinical trials, therefore, were undertaken in order to evaluate the effectiveness of AZA as a depigmenting agent and as a chemotherapeutic agent. Twenty-seven uniformly black pigmented guinea pigs were given topical applications of various concentrations (3, 5, 10, 15, and 20%) of AZA preparations for 8 weeks, and their effects on the melanocytes of epilated skin of the backs and the nonepilated ears of guinea pigs were compared to the effects of well-known depigmenting agents. Whereas 4-isopropylcatechol, monobenzylether of hydroquinone, monoethylether of hydroquinone, hydroquinone, and 4-hydroxyanisole were found to be selectively cytotoxic to melanocytes in black-skinned guinea pigs, AZA has little or no visually recognizable effect on melanocytes in these animals. The therapeutic effect of local s.c. injections of various concentrations of AZA preparations on the development of s.c. implanted B-16 melanoma tumor was evaluated in 96 C57BL/6J mice. In addition, 31 BDF1 mice, implanted i.p. with B-16 melanoma tumor, were used to assess the effect of 100-500 mg/kg concentrations of AZA administered i.p. In both studies, AZA revealed no significant tumoristatic or tumoricidal effect on the size, color, and growth of melanoma. The effect of AZA was also evaluated on S-91A (melanotic or pigmented) and S-91B (amelanotic) human melanoma cells in culture. Low concentrations (10(-5) and 10(-3) M) of AZA had no inhibitory effect on the growth of these cells. Only at higher concentrations (greater than 10(-3) M) was a cytotoxic effect on cell viability observed. These observations indicate AZA is not selectively cytotoxic to normal and proliferative melanocytes and has no apparent inhibitory effect on the formative process of melanin pigmentation.

Animals↗
PubMed1985

Ocular findings in patients treated with PUVA.

This 5-year prospective study of ophthalmologic findings in 1299 patients treated with oral 8-methoxypsoralen photochemotherapy (PUVA) for psoriasis failed to demonstrate a significant dose-dependent increase in the risk of developing symptomatic cataracts. These patients were instructed to wear UVA-blocking eyeglasses when exposed to sunlight and during treatment for a 12-h period beginning from the time of 8-methoxypsoralen ingestion. However, we did observe a small increase in the risk for development of nuclear sclerosis and posterior subcapsular opacities among patients who received at least 100 PUVA treatments, compared to patients with fewer than 100 treatments (relative risk = 2.3 and 3.0, respectively; p less than .05 both comparisons). We compared our results to those of a large, population-based study and found, after adjusting for differences in methods, that the prevalence of cataracts in our study patients, aged 52-75 years, was not significantly different. Since the latency period for development of symptomatic ocular abnormalities may be longer than 5 years, continued surveillance of our cohort and continued use of appropriate ocular protection by all patients treated with PUVA is indicated.

Aged↗
PubMed1985

Melanin macroglobules as a cellular marker of neurofibromatosis: a quantitative study.

To investigate the usefulness of melanin macroglobules (MMG) as a cellular marker for neurofibromatosis, their density was quantified in biopsies of café-au-lait spots (macules) (CALM) from 22 patients with von Recklinghausen's neurofibromatosis, 6 patients with bilateral acoustic neurofibromatosis, and 19 controls. The density of MMG was significantly higher in biopsies of the CALM of patients with von Recklinghausen's neurofibromatosis than in patients with bilateral acoustic neurofibromatosis (p less than .01) or controls (p less than .0008). The mode of acquisition of von Recklinghausen's neurofibromatosis (inherited vs new mutation) was not related to the density of MMG. On light microscopy, 14/22 (64%) patients with von Recklinghausen's neurofibromatosis had 11 or more MMG per 5 high-power fields. In contrast, none of the other two groups had more than 10 MMG per 5 high-power fields.

Adolescent↗
PubMed1984

Cigarette smoking and malignant melanoma. Prognostic implications.

Heavy cigarette smoking (current smoking with greater than 15-pack-year smoking history), along with 13 other variables, were tested for their ability to predict death in 196 patients with clinical Stage I melanoma. A stepwise proportional hazards general linear model (Cox multivariate analysis) showed that although heavy cigarette smoking as a single variable is an adverse prognostic marker (P = 0.0065), it has only suggestive prognostic significance once thickness factors are taken into account (P = 0.0747). People who stopped smoking had the same survival as nonsmokers. Clinical Stage I patients with melanoma who were heavy smokers presented with thicker lesions than their nonsmoking counterparts (P = 0.037). Although cigarette smoking may play a role in the biologic behavior of melanoma by mediating an effect on thickness, it need not be considered as an independent stratification criterion when analyzing results of melanoma prognosis or treatment.

Adult↗
PubMed1984

Cutaneous squamous-cell carcinoma in patients treated with PUVA.

A 5.7-year prospective study of 1380 patients treated for psoriasis with oral methoxsalen (8-methoxypsoralen) and ultraviolet A photochemotherapy (PUVA) revealed that after adjustment for exposures to ionizing radiation and topical tar preparations, the risk that cutaneous squamous-cell carcinoma would develop at least 22 months after the first exposure to PUVA was 12.8 times higher in patients exposed to a high dose than in those exposed to a low dose (95 per cent confidence interval, 5.8 to 28.5). No substantial dose-related increase was noted for basal-cell carcinoma. The dose-dependent risk of cutaneous squamous-cell carcinoma suggests that PUVA can act as an independent carcinogen. In our study, morbidity associated with these tumors has been limited, but further follow-up is needed. Meanwhile, patients treated with PUVA should be followed closely for the possible development of cutaneous squamous-cell carcinoma.

Adult↗
PubMed1984

Late recurrence (beyond ten years) of cutaneous malignant melanoma. Report of two cases and a review of the literature.

Two patients experienced a recurrence of cutaneous malignant melanoma more than ten years after initial diagnosis, treatment, and presumed cure. A review of the literature shows that delayed metastases (more than ten years) have been clearly documented in only seven previous patients with cutaneous malignant melanoma. With the rising incidence of cutaneous malignant melanoma, physicians may begin to see more cases of late recurrence in patients with a history of presumably cured disease. Although uncommon, late recurrence has important implications in the long-term management of all patients with malignant melanoma.

Adolescent↗
PubMed1984

Conservative surgical management of superficially invasive cutaneous melanoma.

Between 1976 and 1980, 136 patients were evaluated for primary treatment of cutaneous melanoma. Forty-nine lesions were invasive to Clark's Level II (38 patients) or III (11 patients) with a thickness of 0.3 to 1.2 mm. Conservative re-excision was advised as definitive therapy for these patients. The margin of resection was defined as the maximum excision that would allow primary closure of the wound. Pathology reports of the re-excised specimens revealed the narrowest margins to be 0.7 to 4 cm. Unexpected residual tumor was present in 2 specimens and melanocytic hyperplasia in 12 specimens. After a follow-up period of 2.5 to 7.0 years, there have been no local recurrences. One patient developed regional lymph node metastases 16 months and, then central nervous system (CNS) metastases 25 months after primary treatment. A second patient died with pulmonary metastases 4.5 years after initial therapy. Melanomas that are not deeply invasive do not require wide excision and skin grafting for local control. Occasionally these thin lesions do produce systemic metastases, emphasizing the need for long-term follow-up of even "low-risk" patients.

Adult↗