Cutaneous Myoepithelioma | Case Study

epidermal Myoepithelioma Case StudyTITLE Cutaneous myoepithelioma A causal agent report of an unusual and recently recognized entity rookMyoepitheliomas and mix neoplasms were precisely recently recognized to choke primarily in loose wander, and nevertheless small case numbers have been described. The break case is of 25-year-old male who had solitary, painless mass over right midst finger, measuring 3cm in greatest dimensions and light microscopy revealed a tumor be of a mingled existence of spindle, epithelioid and plasmacytoid cells arranged nigh a commutation chondromyxoid stroma. No decided diagnosis could be reached on this morphology and initial diagnosis of kind mixed stromal tumor was considered. Immunohistochemistry(IHC) was performed and the tumor showed strong positivity for Calponin and SMA, Ki-index showed low index, weak and focal positivity for S-100 and veto for Pan-CK. The final diagnosis of benign myoepithelioma was entertained.Keywords Myoepi thelioma, Cutaneous, Soft meanderINTRODUCTIONMyoepithelioma of the skin and flabby create from raw stuff is a newly recognized entity only ten years past with fewer than 50 case reports. It has characteristic histopathologic and immunohistochemical features, which need to be severalize from a variety of tumorsCASE REPORTCase history A 25-year-old male presented with a solitary, painless mass over right center of attention finger, measuring 3cm in greatest dimension since 6months. There is no subjoin in size and overlying skin is smooth and unremarkable. The mass is firm, non- adoring and mobile. X-ray showed a soft meander mass with underlying mug up unremarkable.GrossMultiple tissue bits aggregate measuring 321cm and skin flap measuring 21cm.Light microscopyRevealed a tumor in the superficial dermis composed of a mixed population of spindle , epithelioid, and plasmacytoid cells arranged around a central chondromyxoid stroma. No definite diagnosis could be reached on this morphology and diagnosis of benign mixed stromal tumor was considered.Immunohistochemistry(IHC)IHC was performed and showed strongly prescribed Calponin and SMA. S-100 was weak and focally positive. Pan CK was negative. Ki 67 revealed low index (2%).The final diagnosis of Benign myoepithelioma was entertained. first derivative DIAGNOSISThe primary first derivative diagnoses considered were extraskeletal myxoid chondrosarcoma (EMC) and ossifying fibromyxoid tumor (OFMT). EMC typically shows a multinodular produce pattern with cords of cells in a myxoid matrix. The tumor cells in EMC ar more spindled than those of myoepitheliomas. S-100 proteinand epithelial markers atomic number 18 convey in a minority of EMC and usually only focally,while both the markers are often extensively expressed in myoepitheliomas. OFMT isa lobulated tumor surrounded by a rim of metaplastic b wholeness. The tumor cells are closelypale-staining ovoid to round cells. near 70% of OFMT show positivity f orS-100 protein and vimentin and 50% of tumor cells are positive for desmin. The tumorcells in OFMT are rarely positive for epithelial markers and GFAP. Myoepitheliomas aregenerally negative for desmin, nearly half positive for GFAP, and nearly invariably showpositivity for keratin and S-100 protein.1Other tumors that should be differentiated are, Epithelioid benign fibrous histiocytoma that usually shows a superficial dermal tumor with a well-developed epidermal collarette. Spitz nevus is characterized by a junctional component, nesting and maturation of tumor cells. In epithelioid sarcoma, multiple tumor nodules around central necrosis or as yet myxoid degeneration are often seen. More morphologic uniformity is detect in epithelioid sarcoma over myoepithelioma. Moreover, approximately 90% of epithelioid sarcoma are positive for vimentin, cytokeratin, and EMA, and around 60% are positive for CD34, but are generally negative for other markers typical myoepithelial specialisation (S-100 protein, GFAP, myogenic markers). Cellular neurothekeoma consists of nesting of tumor cells, and are systematically S-100 negative.2COMMENTTumors comprised just aboutly of myoepithelial cells without obvious epithelial differentiation are designated myoepitheliomas.1 Neoplasms of myoepithelial cells back tooth occur in a pure form as myoepitheliomas or in association with secretory organular structures as mixed tumors.2 Myoepitheliomas of the skin and soft tissue were recognized only 10 years ago.3 Myoepithelial cells usher out point dual epithelial and myoid differentiation. They may as well as show different metaplasia, including squamous, adipocytic, bone and cartilaginous differentiation.4,5 As a consequence, proliferating myoepithelial cells in neoplasms give away a variety of histologic and immunohistochemical behavior patterns. It has been postulated that dermic myoepitheliomas are related to mixed tumors of skin and that soft tissue myoepitheliomas are der ived from deeply located adnexal structures. Cutaneous myoepitheliomas of the head and neck may be derived from salivary secretory organ tissue, as has been reported in two parotid secreter myoepitheliomas presenting as infra- auricular subcutaneous masses.6 Therefore, the possibility of an underlying primary salivary gland neoplasm should be considered in myoepitheliomas presenting in the head and neck.Myoepithelial tumors were described only recently in soft tissue, and, to date, fewer than 50 cases have been reported. Kilpatrick et al 3 reported a get wind of 19 patients with mixed tumors and myoepitheliomas of soft tissue in 1997. Michal et al 7 reported 12 additional cases of myoepitheliomas of the skin and soft tissues in 1999, Hornick and Fletcher conducted a study of 14 cutaneous myoepitheliomas. There were 11 males and 3 females. The study indicated that cutaneous myoepitheliomas occur with peaks in childhood (7 patients were in the midst of 10 and 20 years of age) and middle age and are most common on the extremities, in contrast to mixed tumors of the skin, which typically occur on the head and neck in middle aged or elderly adults.1,3,4Myoepitheliomas of soft tissue are often lobulated, and the most rat architecturalpattern is reticular or trabecular with chondromyxoid or hyalinized stroma. These lesions dis monkey the same wide range of histologic features as those of salivary gland origin.M whatsoever tumors are heterogeneous, containing an admixture of epithelioid and spindled cells, reticular areas merging with steadfast areas, at least focally prominent stroma, and occasional foci of cartilaginous or gaunt differentiation. 8 A small subsetof tumors approximately 10% are predominantly solid proliferations of spindled or plasmacytoid myoepithelial cells. Occasional tumors display features of so-called parachordoma, namely, large epithelioid cells with eosinophilic epitheliomas. Initially, myoepitheliomas were only recognized to contain s pindled or plasmacytoid cells growing in solid sheets. 9Current classifications consequently include all of these patterns within the spectrum of myoepithelioma, simply separating those tumors with ductal differentiation into the mixed tumor category.10,11 Whereas some investigators allow up to 5% or 10% ductal differentiation in myoepitheliomas, others classify tumors with any ducts as mixed tumors. In any event, it is now widely thought that myoepitheliomas and mixed tumors fall along a spectrum of tumors with overlapping histologic appearances and similar clinical behavior. Because the immunophenotype of these lesions overlaps with myoepithelioma, and otherwise typical myoepitheliomas can show focal areas with parachordoma-like features, it is becoming increasingly clear that parachordoma probably go within the spectrum of myoepithelioma of soft tissue, as is reflected in the new WHO classification.11 The only discernible difference in immunophenotype is GFAP and SMA negativit y in parachordomas, because few cases of parachordoma have been study and only about 50% of otherwise convincing soft tissue myoepitheliomas are GFAP positive and only around 40% are SMA-positive, consequently this distinction seems very questionable. Awareness of the wide morphologic range of myoepitheliomas is infallible to perform confirmatory immunohistochemical stains and thereby to arrive at the correct diagnosis.12 In salivary glands, myoepitheliomas are generally positive for cytokeratins and S-100 protein, whereas immunostaining for actin and GFAP is variable. We therefore required immunoreactivity for every keratin or EMA, in conjunction with detection of S-100 protein or myogenic markers, for the diagnosis of myoepithelioma and inclusion in this series. Neoplastic myoepithelial cells of all morphologic types often expressed myogenic markers.13 As has been reported in the salivary gland, we found calponin to be the most sensitive myogenic marker, staining 86% of tumors, whereas SMA stained 36% and desmin only a small subset (14%). Interestingly, the lowly cell/myoepithelial marker p63, which has shown utility in the differential diagnosis of carcinoma of breast and prostate due to the staining of myoepithelial or basal cells in in situ lesions, appears to be detectable in only one fourth of soft tissue myoepithelial tumors. Immunostaining for p63 is not specific for myoepithelial tumors, however, as this antigen has also been reported in other neoplasms, especially squamous cell and urothelial carcinomas.13,14 Nonetheless, detection of p63 expression may provide helpful supportive evidence of myoepithelial differentiation in the proper morphologic context.CONCLUSIONCutaneous myoepitheliomas are relatively rare. Pathologists play an important role in reaching to accurate morphological diagnosis. Myoepitheliomas should be considered in the differential diagnosis of cutaneous and soft tissue tumors. Immunohistochemical study may aid in the diagnosis . Although most cutaneous and soft tissue myoepitheliomas behave in a benign fashion, there is a fundamental risk for local recurrence and a low metastatic potential. wide of the mark excision with safe surgical margins and regular follow-up are critical for the management of cutaneous and soft tissue myoepitheliomas.References1. Hornick JL,Fletche CDM. Myoepithelial tumors of soft tissue a clinicopathologic and Immunohistochemical study of 101 cases with evaluation of prognostic parameters. Am J Surg Pathol. 20032711831196.2. Hornick JL, Fletcher CD. Cutaneous myoepithelioma a clinicopathologic and immunohistochemical study of 14 cases. Hum Pathol. 20043514-24.3. Kilpatrick SE, Hitchcock MG, Kraus MD, Calonje E, Fletcher CD. combine tumors and myoepitheliomas of soft tissue a clinicopathologic study of 19 cases with a merge concept. Am J Surg Pathol. 19972113-22.4. Mentzel T, Requena L, Kaddu S et al. Cutaneous myoepithelial neoplasms clinicopathologic and immunohistochemical study of 20 cases suggesting a continuous spectrum ranging from benign mixed tumor of the skin to cutaneous myoepithelioma and myoepithelial carcinoma. J Cutan Pathol. 200330294-302.5. Fernndez-Figueras MT, Puig L, Trias I, Lorenzo JC, Navas-Palacios JJ. Benign myoepithelioma of the skin. Am J Dermatopathol. 199820208-12.6. Lewin MR, capital of Alabama EA, Barrett TL. New or unusual dermatopathology tumors a review. J Cutan Pathol. 201138689-96.7. Kutzner H, Mentzel T, Kaddu S et al. Cutaneous myoepithelioma an under-recognized cutaneous neoplasm composed of myoepithelial cells. Am J Surg Pathol. 200125348-558. Dix BT, Hentges MJ, Saltrick KR, Krishnamurti U. Cutaneous myoepithelioma in the foot case report. Foot Ankle Spec. 20136239-41.9. Michal M, Miettinen M. Myoepitheliomas of the skin and soft tissues. Report of 12 cases. Virchows Arch. 1999434393-400.10. Franklin G, Chen S, Sznyter LA, Morgenstern NJ. Cutaneous myoepithelioma with a plexiform pattern of growth a case report. J Cutan Pathol. 20093642-5.11. Jo VY, Antonescu CR, Zhang L et al. Cutaneous Syncytial Myoepithelioma Clinicopathologic Characterization in a Series of 38 Cases. Am J Surg Pathol. 2013 37 710718.12. Jakate K, Wong K, Sirbovan J, Hanna W. Cutaneous myoepithelioma arising within hidradenoma of the scalp. J Cutan Pathol. 201239279-85.13. Stojsic Z, Brasanac D, Boricic I, Bacetic D. lapse cell myoepithelial carcinoma of the skin. A case report. J Cutan Pathol. 200936680-3.14. Tanahashi J, Kashima K, Daa T, Kondo Y, Kuratomi E, Yokoyama S. A case of cutaneous myoepithelial carcinoma. . J Cutan Pathol. 200734648-53.LEGENDS Figure 1Myoepithelioma(100X) composed of a mixed population of spindled, epithelioid, and plasmacytoid cells arranged around a central chondromyxoid stroma. go into shows 400X view and reveals mild nuclear atypia (coarse chromatin and prominent nucleoli) .Figurer 2Myoepithelioma(400X) (a)shows SMA positivity in the cytol of myoepithelial cells.(b) shows strong positi vity for Calponin in the cytoplasm of spindle cells.(c) shows PAN CK negativity(d) showsS100 negativity.Figure 3 Myoepithelioma(400X) shows Low Ki 67 index.