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Melanocytic Neoplasms (melanocytic + neoplasm)
Selected AbstractsFrequency of Seborrheic Keratosis Biopsies in the United States: A Benchmark of Skin Lesion Care Quality and Cost EffectivenessDERMATOLOGIC SURGERY, Issue 8 2003Maria I. Duque MD Background. Most seborrheic keratoses may be readily clinically differentiated from skin cancer, but occasional lesions resemble atypical melanocytic neoplasms. Objective. To evaluate the frequency, cost, and intensity of procedures performed that result in the removal and histopathologic evaluation of seborrheic keratoses. Methods. Episodes of surgical removal of lesions that were identified as seborrheic keratoses by histologic identification were determined using Medicare Current Beneficiary Survey data from 1998 to 1999. These episodes were defined by a histopathology procedure code that is associated with a diagnosis code for seborrheic keratosis. We then identified what procedure(s) generated the histopathology specimen. Biopsy and shave procedures were considered "low intensity," whereas excision and repair procedures were considered "high intensity." Results. Dermatologists managed 85% of all episodes of seborrheic keratoses. Dermatologists managed 89% of seborrheic keratosis episodes using low-intensity procedures compared with 51% by other specialties. For nondermatologists, 46% of the treatment cost ($9 million) to Medicare was generated from high-intensity management compared with 15% by dermatologists ($6 million). Conclusion. There is a significant difference in the management of suspicious pigmented lesions between dermatologists and other specialists. This affects both the cost and quality of care. [source] Immunohistochemical characteristics of melanomaJOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2008Steven J. Ohsie Melanoma has a wide spectrum of histologic features which mimic epithelial, hematologic, mesenchymal, and neural tumors. Immunohistochemistry has been the primary tool to distinguish melanomas from these other tumors; it has also been studied for use as an adjunct to distinguish benign and malignant melanocytic tumors and to elucidate prognosis. Furthermore, there has been extensive effort to find a suitable marker to differentiate spindle cell and desmoplastic melanoma from other tumors. We have reviewed the literature investigating melanocytic differentiation markers, proliferation markers, immunomodulatory markers, signaling molecules, and nerve growth factors and receptors. Despite the proliferation of immunohistochemical markers, S-100 remains the most sensitive marker for melanocytic lesions, while markers such as HMB-45, MART-1/Melan-A, tyrosinase, and MITF demonstrate relatively good specificity but not as good sensitivity as S-100. No marker has proven useful in distinguishing spindle cell and desmoplastic melanomas from other tumors. Ki67 remains the most useful adjunct in distinguishing benign from malignant melanocytic tumors. None of the markers reviewed has been shown conclusively to have prognostic value for melanocytic neoplasms. [source] Discordance in the histopathologic diagnosis of difficult melanocytic neoplasms in the clinical settingJOURNAL OF CUTANEOUS PATHOLOGY, Issue 4 2008Saurabh Lodha Background:, The gold standard for diagnosing melanocytic neoplasms is by histopathologic examination. However, lack of agreement among expert dermatopathologists in evaluating these tumors has been well established in experimental settings. Objective:, This study examines the discordance among dermatopathologists in evaluating difficult melanocytic neoplasms in a clinical setting where the diagnosis impacts patient management. Methods:, Retrospective review of consultation reports over a 6-year period. Results:, There was complete agreement among the consultants in 54.5% of the cases. However, a high level of disagreement was found in 25% of the cases. Limitations:, The analysis was limited to two consultant dermatopathologists. Conclusions:, There are limitations to the practical applications of histologic criteria for diagnosing difficult melanocytic tumors. It is not malpractice for a pathologist to have rendered a diagnosis that did not predict clinical outcome as long as ,standard of care' has been followed in his/her evaluation of the specimen. [source] Loss of claudin-1 expression in tumor-associated vessels correlates with acquisition of metastatic phenotype in melanocytic neoplasmsJOURNAL OF CUTANEOUS PATHOLOGY, Issue 8 2005Michael L. Cohn Recent studies have suggested that some metastatic solid tumors lack claudin expression. It is unknown whether claudins play a role in cutaneous melanoma. Immunohistochemical studies were performed on tissue microarrays containing 19 benign melanocytic nevi (BN), 21 dysplastic nevi (DN), 23 primary malignant melanomas (MMs), and 31 metastatic melanomas (MMMs) using a polyclonal anti-claudin-1 antibody. Immunoreactivity in tumor cells and associated vessels was graded by intensity and by percentage of reactive cells. Normal epidermis served as internal control (3+ labeling). Cases with at least 2+ labeling in more than 25% of the cells were considered positive. Claudin-1 expression was present in 37% of BN, 24% of DN, 26% of MM, and 3.2% of MMM. Tumor-associated vessels showed the following results: 11 of 19 (58%) in BN, 14 of 21 (67%) in DN, 17 of 23 (74%) in MM, and 6 of 31 (19%) in MMM. A significant loss of expression was noted between MMM and all other lesions in tumor cells and associated vessels. There was no significant difference between BN, DN, and MM. Within primary melanomas, there was a significant correlation between expression of claudin in tumor cells and Clark level/Breslow thickness. Also significant was a decreased expression of claudin in tumor vessels of lesions with higher Breslow thickness or Clark level. These data suggest that loss of claudin-1 may play a significant role in the acquisition of metastatic phenotype in cutaneous melanoma. [source] Increasing Expression of the Retinoic X Receptor-B During Malignant Melanoma ProgressionJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005S.J. McAlhany Retinoic X receptor-b (RXR-b) is a heterodimerization partner for vitamin D receptor (VDR). 1,25-dihydroxyvitamin D3 activation of VDR leads to growth inhibition in numerous cell lines, including some melanoma lines. Evaluation of VDR and RXR-b expression in vivo in melanocytic neoplasms will increase our understanding of this pathways potential role in growth control. Previous studies in our laboratory showed decreased VDR expression in superficially invasive melanoma, and progressive loss of expression in deeply invasive melanomas and metastatic melanomas (MET). We next sought to evaluate RXR-b expression. Twenty-eight melanocytic neoplasms including 8 melanomas in situ (MIS), 9 primary invasive melanomas (PIM), and 11 MET were evaluated for RXR-b expression by immunohistochemistry. Nuclear labeling was assessed as 0 (0%), 1+(<5%), 2+(>5% but <50%), or 3+(>=50%). A significant increase in RXR-b expression from low (0,1+) to high (>1+) was found when comparing MIS to PIM and MET (chi2 p < 0.05). These data suggest: 1) potential loss of 1,25-dihydroxyvitamin D3 induced growth inhibition during melanoma progression may be due to decreased VDR expression without concomitant loss of RXR-b; and 2) increased RXR-b expression during melanoma progression may offer selective advantage through alternative signaling pathways. [source] Cadherin expression pattern in melanocytic tumors more likely depends on the melanocyte environment than on tumor cell progressionJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2004Sven Krengel Background:, Adhesion molecules have been assigned an important role in melanocytic tumor progression. By the loss of E-cadherin, melanocytes might escape the control of neighbouring keratinocytes. Although in vitro data support this hypothesis, there are yet no conclusive immunohistochemical results on cadherin expression in melanocytic tumors. Objective:, To gain detailed insight in the expression of cadherins and their cytoplasmic binding partners, the catenins, in various types of benign and malignant melanocytic neoplasms. Methods:, Immunohistochemical analysis of the expression of E-, P-, and N-cadherin and ,-, ,-, and ,-catenin in compound and dermal nevi, Spitz nevi, blue nevi, ultraviolet B (UVB)-irradiated nevi, and malignant melanomas of various tumor thickness. Results:, In both nevi and melanomas, E-cadherin expression in melanocytic cells decreased, following a gradient from junctional to deeper dermal localization. The pattern of E-cadherin expression was more heterogeneous in melanomas than in nevi. In some melanomas, E-cadherin was only weakly positive in the epidermal tumor cells. P-cadherin expression was similar to that of E-cadherin. N-cadherin expression in melanocytic lesions was a rare finding, however, a small percentage of melanomas showed expression in some cell nests. Some Spitz nevi exhibited strong N-cadherin immunoreactivity. Most melanocytic cells were ,- and ,-catenin-positive and ,-catenin-negative. UVB irradiation did not influence the expression of cadherins and catenins in melanocytic nevi in vivo. Conclusions:, It is presumed that the gradual loss of E-cadherin expression represents a reaction of melanocytic cells to altered conditions in the dermal environment, e.g. lack of contact to keratinocytes, or new contact with dermal extracellular matrix molecules, respectively. Melanoma cells apparently are less dependent on these environmental factors and, therefore, show a more heterogeneous expression pattern. This might be of importance for the adaptation of the tumor cells to local requirements. However, in view of our results, a causative role of (loss of ) E-cadherin or (gain of ) N-cadherin for melanocytic tumor progression still remains to be proven. [source] Histologic features of melanocytic nevi seen in association with mycosis fungoidesJOURNAL OF CUTANEOUS PATHOLOGY, Issue 10 2003Jennifer M. McNiff Background:, Many different tumors have been reported to occur simultaneously as collision lesions. To date, no such events have been reported between mycosis fungoides (MFs) and melanocytic neoplasms. Methods:, Two cases are presented in which patches of MF were superimposed on melanocytic nevi. In addition, 967 biopsies of MF from 411 patients were identified in an 8-year retrospective database search. Patient pathology history summaries were reviewed to identify inflamed nevi, atypical nevi, and melanoma submitted for histologic evaluation from this population. Results:, The occurrence of MF in a congenital nevus was associated with a halo phenomenon restricted to the affected region of the nevus in one patient. In the other patient, nests of two morphologies (lymphocytic and melanocytic) in the same biopsy presented a potentially confusing histologic picture. No other cases of MF superimposed on a nevus were identified in 967 biopsies from 411 patients with a histological diagnosis of MF seen over the past 8 years. In this population, 57 biopsies of melanocytic lesions were identified from 28 patients, including three atypical nevi and three melanomas. Conclusions:, The presence of MF superimposed on a nevus is rare and may lead to confounding histologic features or the development of a halo nevus phenomenon. [source] Under the microscope: doctors, lawyers, and melanocytic neoplasmsJOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2003Earl J. Glusac Misdiagnosed melanoma remains one of the most common causes of lawsuits in histopathology. Reasons for this are discussed in conjunction with relevant literature, common errors in diagnosis, and strategies to avoid them. [source] Epidemiology of conjunctival melanocytic neoplasmsACTA OPHTHALMOLOGICA, Issue 2008T KIVELÄ Purpose To summarise the epidemiology of conjunctival melanocytic neoplasms. Methods Review of population-based data on 85 patients with primary conjunctival melanoma (CM) and recently published literature. Results CM accounts for 5-7% of ocular melanoma in Europe. Its age-adjusted incidence has increased 2-fold in North Europe (Finland, from 0.40 to 0.80/million) and North America (USA, from 0.27 to 0.54) during the last 25 y. In both regions, age-adjusted incidence is higher in men. Different rates between regions result from differences in registries, ethnicity and solar radiation. Age-adjusted incidence of CM is 3-fold in non-Hispanic Caucasians and 2-fold in Hispanics relative to Asians, African Americans and American Indians; among non-Hispanic Caucasians it increases 2.5-fold from 48 deg. (e.g. Paris) to 21 deg. (e.g. Mecca) of latitude. CM is rare below 30 y of age (age-specific incidence, 0.06) but increases steadily thereafter (0.48, 1.05 and 1.57 for 30-49, 50-70 and >70 y, respectively). Median age at diagnosis is 58-60 y. Most CM arise in limbal (57-64%) followed by bulbar (12-13%), palpebral (7-9%) and caruncular (3%) conjunctiva. Tumor-specific 5-and 10-y mortality estimates are 14-20% and 29-38%, respectively. Non-limbal location, increasing tumor thickness and local recurrence are consistently associated with higher mortality. Clinically detectable primary acquired melanosis (PAM) and nevus precede or accompany CM in 57-61% and 7-23% of patients, respectively. Median age at diagnosis of PAM is 56 y. The risk of malignant change is not precisely known and depends heavily on subtype of PAM, ranging from 10 to 90%. Conclusion Recent studies provide epidemiological data on CM which are remarkably consistent. The epidemiology of conjunctival nevi and PAM is less precisely known. [source] Pathology of conjunctival melanocytic neoplasmsACTA OPHTHALMOLOGICA, Issue 2008SE COUPLAND Purpose To describe the classification, grading and staging of conjunctival melanocytic proliferation. Methods We have audited our experience with conjunctival melanomas, using a novel mapping system and have found shortcomings in the current Tumour Node Metastasis (TNM) staging system. We have also reviewed our cases of intra-epithelial melanocytic neoplasia and confirmed other authors' impressions that conjunctival ,primary acquired melanosis with atypia' is histologically similar to cutaneous in situ melanoma. To improve objectivity in the reporting of conjunctival intra-epithelial melanocytic neoplasia, we propose a scoring system based on pattern of melanocytic infiltration, density of melanocytes & degree of cellular atypia. Results The term ,conjunctival melanosis' should be used only to describe the slit-lamp appearance of hyperpigmentation. Histologically, this abnormality should be categorized as ,hypermelanosis' or ,melanocytosis'. Hypermelanosis can either be primary or secondary to ocular or systemic disease. Benign melanocytosis comprises conjunctival melanocytic hyperplasia and naevi. Malignant melanocytosis is essentially melanoma, which is primary (in situ or invasive) or secondary (i.e., spreading to conjunctiva from adjacent tissues) or rarely metastatic. We suggest that the TNM staging system for conjunctival melanoma should be revised to: (1) include a Tis stage; (2) take account of superficial extent, invasion of adjacent tissues and caruncular involvement, in stages TI to TIII; and (3) to sub-categorize TIV disease so that there is better correlation with likely mortality. Conclusion We have revised the classification of conjunctival melanocytic proliferations & improved the grading and staging of melanoma. These developments should be useful in treatment & research. [source] | ||||||||||