Myxofibrosarcoma (MFS) is one of the most common sarcomas of adults, and includes lesions ranging from low to high grade based on increasing cellularity, nuclear pleomorphism, and mitotic activity. We present an unusu...Myxofibrosarcoma (MFS) is one of the most common sarcomas of adults, and includes lesions ranging from low to high grade based on increasing cellularity, nuclear pleomorphism, and mitotic activity. We present an unusual case of MFS, which initially showed features of a pleomorphic hyalinizing angiectatic tumor (PHAT), a rare soft- tissue tumor considered benign in the WHO classification. The initial lesion showed a subcutaneous proliferation of spindled to polygonal eosinophilic cells with striking cellular pleomorphism, set in amyxoid to sclerotic stroma with prominent hyalinized and angiectatic vasculature, classic characteristics of PHAT. Rare mitotic figures were identified. The preliminary diagnosis of PHAT was confirmed by a consultant expert soft- tissue pathologist. Four months after the initial surgery, local recurrencewas noted. The recurrent tumor demonstrated findings of a high- grade MFS, with a diffuse and cellular proliferation of atypical spindle cells set in a prominent myxoid stroma. Multiple mitoses, including atypical ones, were present. In light of these findings, the original specimen was reexamined and the initial diagnosis was amended to MFS. MFS may mimic or be confused with several benign soft- tissue lesions. Cases mimicking PHAT have not been previously reported. We describe a unique case of a high- grade MFS that initially showed characteristic features of a PHAT, to illuminate the fact that MFS may rarely arise in, or have areas that masquerade as, PHAT. It is also conceivable, although speculative, that at least some cases of PHAT, currently considered a benign tumor by the WHO, may actually represent or evolve into a unique form of MFS of low malignant potential.展开更多
Squamous cell carcinoma is one of the most common primary cutaneous carcinomas but on rare occasion, metastatic squamous cell carcinoma from a distant site or solid organ can present as a cutaneous lesion. Most metast...Squamous cell carcinoma is one of the most common primary cutaneous carcinomas but on rare occasion, metastatic squamous cell carcinoma from a distant site or solid organ can present as a cutaneous lesion. Most metastases occur as dermal nodules or involve the dermal lymphatics, but when they are intimately associated with the epidermis, distinguishing the lesion as primary or metastatic may be extremely difficult and usually requires a clinical history or high index of suspicion. A 71- year- old woman presented with multiple eruptive nodules over her chest, flank, and back. Histologically the lesions appeared to be arising from the surface epithelium and consisted of atypical, predominantly spindle cells, some of which streamed off of the epidermis. Following the initial evaluation, a history of breast carcinoma with subsequent radiation therapy and ultimate mastectomy was obtained, and the original breast biopsy and mastectomy material was reviewed. After performing additional studies, it became clear that the origin of the carcinomas was metastatic from an underlying metaplastic breast carcinoma.展开更多
Plaque formation is a characteristic finding in patients with psoriasis and re flects cytokine-induced keratinocyte proliferation and/or impaired apoptosis of keratinocytes. Antithyroid thioureylenes such as propylthi...Plaque formation is a characteristic finding in patients with psoriasis and re flects cytokine-induced keratinocyte proliferation and/or impaired apoptosis of keratinocytes. Antithyroid thioureylenes such as propylthiouracil (PTU) and met himazole (MMI) are effective in the treatment of plaque psoriasis. Following PTU and MMI treatment, proliferative cell nuclear antigen (PCNA) expression is sign ificantly reduced, suggesting that these medications have an antiproliferative effect. p 16 is an antiapoptotic protein that is present in relative abundance in psoriati c plaques and is believed to play a potential role in the persistent senescence and impaired apoptosis of the keratinocytes in the plaque. This study examined p 16 expression in biopsy samples of eight patients with plaque psoriasis given 30 0 mg of propylthiouracil in divided doses for 3 months. Despite significant clin ical and histological improvement with PTUtreatment,p16expressionwasessentiallyu nchanged,suggesting that the beneficial effect of PTU in psoriasis is not mediat ed through a decrease in p16 expression. The effect of PTU on other antiapoptoti c proteins such as bcl-xL remains to be determined.展开更多
文摘Myxofibrosarcoma (MFS) is one of the most common sarcomas of adults, and includes lesions ranging from low to high grade based on increasing cellularity, nuclear pleomorphism, and mitotic activity. We present an unusual case of MFS, which initially showed features of a pleomorphic hyalinizing angiectatic tumor (PHAT), a rare soft- tissue tumor considered benign in the WHO classification. The initial lesion showed a subcutaneous proliferation of spindled to polygonal eosinophilic cells with striking cellular pleomorphism, set in amyxoid to sclerotic stroma with prominent hyalinized and angiectatic vasculature, classic characteristics of PHAT. Rare mitotic figures were identified. The preliminary diagnosis of PHAT was confirmed by a consultant expert soft- tissue pathologist. Four months after the initial surgery, local recurrencewas noted. The recurrent tumor demonstrated findings of a high- grade MFS, with a diffuse and cellular proliferation of atypical spindle cells set in a prominent myxoid stroma. Multiple mitoses, including atypical ones, were present. In light of these findings, the original specimen was reexamined and the initial diagnosis was amended to MFS. MFS may mimic or be confused with several benign soft- tissue lesions. Cases mimicking PHAT have not been previously reported. We describe a unique case of a high- grade MFS that initially showed characteristic features of a PHAT, to illuminate the fact that MFS may rarely arise in, or have areas that masquerade as, PHAT. It is also conceivable, although speculative, that at least some cases of PHAT, currently considered a benign tumor by the WHO, may actually represent or evolve into a unique form of MFS of low malignant potential.
文摘Squamous cell carcinoma is one of the most common primary cutaneous carcinomas but on rare occasion, metastatic squamous cell carcinoma from a distant site or solid organ can present as a cutaneous lesion. Most metastases occur as dermal nodules or involve the dermal lymphatics, but when they are intimately associated with the epidermis, distinguishing the lesion as primary or metastatic may be extremely difficult and usually requires a clinical history or high index of suspicion. A 71- year- old woman presented with multiple eruptive nodules over her chest, flank, and back. Histologically the lesions appeared to be arising from the surface epithelium and consisted of atypical, predominantly spindle cells, some of which streamed off of the epidermis. Following the initial evaluation, a history of breast carcinoma with subsequent radiation therapy and ultimate mastectomy was obtained, and the original breast biopsy and mastectomy material was reviewed. After performing additional studies, it became clear that the origin of the carcinomas was metastatic from an underlying metaplastic breast carcinoma.
文摘Plaque formation is a characteristic finding in patients with psoriasis and re flects cytokine-induced keratinocyte proliferation and/or impaired apoptosis of keratinocytes. Antithyroid thioureylenes such as propylthiouracil (PTU) and met himazole (MMI) are effective in the treatment of plaque psoriasis. Following PTU and MMI treatment, proliferative cell nuclear antigen (PCNA) expression is sign ificantly reduced, suggesting that these medications have an antiproliferative effect. p 16 is an antiapoptotic protein that is present in relative abundance in psoriati c plaques and is believed to play a potential role in the persistent senescence and impaired apoptosis of the keratinocytes in the plaque. This study examined p 16 expression in biopsy samples of eight patients with plaque psoriasis given 30 0 mg of propylthiouracil in divided doses for 3 months. Despite significant clin ical and histological improvement with PTUtreatment,p16expressionwasessentiallyu nchanged,suggesting that the beneficial effect of PTU in psoriasis is not mediat ed through a decrease in p16 expression. The effect of PTU on other antiapoptoti c proteins such as bcl-xL remains to be determined.
