The conjoint occurrence of follicular, sebaceous, or apocrine differentiations in a cutaneous adnexal neoplasm is a known event, more often encountered in benign neoplasms, whereas reports of cutaneous malignant adnex...The conjoint occurrence of follicular, sebaceous, or apocrine differentiations in a cutaneous adnexal neoplasm is a known event, more often encountered in benign neoplasms, whereas reports of cutaneous malignant adnexal tumors with bilineage or trilineage differentiation are few. A new case of a cutaneous malignant adnexal neoplasm with multidirectional differentiation is reported here. A 57-year-old woman presented with a long-standing, slowly growing, asymptomatic solitary tumor the size of a large nut in the coccygeal area,whichwas surgically excised. Ten years after the surgery, there was no evidence of recurrence or metastasis. Microscopically, the neoplasm was located in the dermis with focal extension into the subcutis. It was asymmetric, horizontally oriented, and mostly composed of small nodules that varied in shape from round and oval aggregations to elongated strands and irregular islands; the nodules were either clustered, formed a jigsaw puzzlelike pattern or were dispersed. The nodules were composed of small basaloid cells sometimes intermixed with larger cells with ample cytoplasm forming glandular structures. Rare nodules resembled elements seen in a spiradenoma by containing scattered lymphocytes and globules of hyalinized eosinophilic basal membrane material. The stroma was paucicellular, but focally it resembled that seen in perifollicular mesenchyme. Mitotic figures, including abnormal ones, were infrequent, but mild nuclear pleomorphism, nuclear crowding, and individual cell necrosis were easily appreciable in both small basaloid cells and cells with clear cytoplasm. Perineural invasion was apparent. We classified this tumor as a well-differentiated adnexal carcinoma demonstrating combined follicular and apocrine differentiation. It differs from previously published cases of malignant adnexal tumors with multidirectional differentiation and further exemplifies the spectrum of diversity encountered in malignant proliferations with differentiation toward the folliculosebaceous-apocrine unit.展开更多
Hamartoma is a neoplasm-like lesion composed of an abnormal mixture of tissues native to the area. We report on an unusual example of a hamartomatous lesion that showed an abnormal mixture of elements of the folliculo...Hamartoma is a neoplasm-like lesion composed of an abnormal mixture of tissues native to the area. We report on an unusual example of a hamartomatous lesion that showed an abnormal mixture of elements of the folliculosebaceous-apocrine unit and arrector pili muscle. A 13-year-old female presented with two nodules situated 2 cm apart on the lower leg that were present since birth. The patient reported some enlargement and slight pain of the otherwise asymptomatic lesions during 2 years, before they were surgically removed. The patient obviously had no skin problems afterwards; her 12-year follow-up was significant for leucopenia and nephrolithiasis. The biopsies from both lesions looked identical. Each lesion was biphasic, i.e. composed of a predominant mesenchymal component and epithelial elements. The mesenchymal part resembled a leiomyoma, or in minor areas, the constituting cells had a myofibroblastic appearance. Encased within the mesenchymal component were large infundibulocystic structures and plentiful grouped and scattered roundish solid epithelial nodules, duct-like, glandular, and tubular elements. Some of the epithelial structures were reminiscent of those seen in tubular apocrine adenoma; others resembled syringomatous elements. We interpreted this unusual lesion as a hamartoma of the folliculosebaceous -apocrine unit.展开更多
文摘The conjoint occurrence of follicular, sebaceous, or apocrine differentiations in a cutaneous adnexal neoplasm is a known event, more often encountered in benign neoplasms, whereas reports of cutaneous malignant adnexal tumors with bilineage or trilineage differentiation are few. A new case of a cutaneous malignant adnexal neoplasm with multidirectional differentiation is reported here. A 57-year-old woman presented with a long-standing, slowly growing, asymptomatic solitary tumor the size of a large nut in the coccygeal area,whichwas surgically excised. Ten years after the surgery, there was no evidence of recurrence or metastasis. Microscopically, the neoplasm was located in the dermis with focal extension into the subcutis. It was asymmetric, horizontally oriented, and mostly composed of small nodules that varied in shape from round and oval aggregations to elongated strands and irregular islands; the nodules were either clustered, formed a jigsaw puzzlelike pattern or were dispersed. The nodules were composed of small basaloid cells sometimes intermixed with larger cells with ample cytoplasm forming glandular structures. Rare nodules resembled elements seen in a spiradenoma by containing scattered lymphocytes and globules of hyalinized eosinophilic basal membrane material. The stroma was paucicellular, but focally it resembled that seen in perifollicular mesenchyme. Mitotic figures, including abnormal ones, were infrequent, but mild nuclear pleomorphism, nuclear crowding, and individual cell necrosis were easily appreciable in both small basaloid cells and cells with clear cytoplasm. Perineural invasion was apparent. We classified this tumor as a well-differentiated adnexal carcinoma demonstrating combined follicular and apocrine differentiation. It differs from previously published cases of malignant adnexal tumors with multidirectional differentiation and further exemplifies the spectrum of diversity encountered in malignant proliferations with differentiation toward the folliculosebaceous-apocrine unit.
文摘Hamartoma is a neoplasm-like lesion composed of an abnormal mixture of tissues native to the area. We report on an unusual example of a hamartomatous lesion that showed an abnormal mixture of elements of the folliculosebaceous-apocrine unit and arrector pili muscle. A 13-year-old female presented with two nodules situated 2 cm apart on the lower leg that were present since birth. The patient reported some enlargement and slight pain of the otherwise asymptomatic lesions during 2 years, before they were surgically removed. The patient obviously had no skin problems afterwards; her 12-year follow-up was significant for leucopenia and nephrolithiasis. The biopsies from both lesions looked identical. Each lesion was biphasic, i.e. composed of a predominant mesenchymal component and epithelial elements. The mesenchymal part resembled a leiomyoma, or in minor areas, the constituting cells had a myofibroblastic appearance. Encased within the mesenchymal component were large infundibulocystic structures and plentiful grouped and scattered roundish solid epithelial nodules, duct-like, glandular, and tubular elements. Some of the epithelial structures were reminiscent of those seen in tubular apocrine adenoma; others resembled syringomatous elements. We interpreted this unusual lesion as a hamartoma of the folliculosebaceous -apocrine unit.
