Kip Amazon

Giant cell fibroblastoma. A report of a case and review of the literature.

A 15-year-old white boy with a giant cell fibroblastoma of the skin of the abdomen is described. Giant cell fibroblastoma is a rare soft tissue neoplasm that most commonly occurs in children as a small, painless mass in the dermis and subcutaneous tissue. Although local recurrences have been reported, no metastases have occurred. Giant cell fibroblastoma must be differentiated from other spindle cell neoplasms.

Metastatic renal cell carcinoma presenting as a parotid tumor: A case report with immunohistochemical findings and a review of the literature

Renal cell carcinoma presenting as an asymptomatic parotid mass is rare. Only 15 cases have been reported. We describe a 72-year-old man with widespread metastatic renal cell carcinoma presenting with a 2-year history of a slowly enlarging left parotid mass. Needle biopsy revealed a clear cell neoplasm. Immunoperoxidase studies for carcinoembryonic antigen were negative while those for vimentin and keratin were positive, consistent with a renal cell carcinoma. This is the first case reported in which the immunohistochemical findings of positive staining for vimentin and keratin have confirmed the presence of metastatic renal cell carcinoma. The histochemical features of various parotid clear cell tumors, as well as a review of renal cell tumors presenting as a parotid mass, will be discussed.

Tuberculous adenitis of the thyroid mimicking subacute thyroiditis

Involvement of the thyroid by Mycobacterium tuberculosis was initially described in the late 18OOs, but it has proven to be a rare occurrence. We describe the case of a nurse who was treated for subacute thyroiditis over a prolonged period before tuberculosis was diagnosed. The clinical, laboratory, and radiologic aspects of the case are presented. The pathogenesis and clinical spectrum of tuberculosis of the thyroid are discussed. CASE REPORT A 36-year-old woman experienced the sudden onset of neck tenderness in May 1985 after an upper respiratory tract infection associated with rhinitis, myalgias, and arthralgias. Her thyroid gland was enlarged and tender; a pertechnetate thyroid scan revealed normal uptake except for an area of decreased uptake in the left lobe. Subacute thyroiditis was suspected, and acetylsalicylic acid was prescribed. Failure to respond to treatment led to the addition of L-thyroxine. She remained intermittently symptomatic with a visually prominent thyroid gland. The left lobe was smooth, firm, and tender. Lymph nodes were not enlarged. Results of thyroid function studies were within normal limits, and the Westergren sedimentation rate was 5 mm/hour. Ultrasonography of the gland in October 1985 revealed a normal gland except for a soft tissue nodule connected to the left lobe. Her chest roentgenogram demonstrated clear lung fields without abnormalities. Six months later, her symptoms persisted. In May of 1986, prednisone was begun, with subsequent improvement of the patient’s symptoms. Ultrasonography at that time demonstrated a 5- by 2-cm hyperechogenic structure associated with the lower pole of the left lobe of the thyroid. A cleavage plane between the structure and left lobe was visible. A fine needle biopsy specimen of the left lobe demonstrated clusters of histiocytes mixed with blood. Scant amounts of colloid were noted. In July of 1986, her neck pain, tenderness, and swelling returned. Computed axial tomography of the neck revealed a multiloculated mass 3.5 cm in diameter anterior to a normal-appearing left lobe of the thyroid. The mass enhanced with contrast and appeared to be encapsulated (Figures 1 and 2). Surgical exploration in October 1986 identified an abscess cavity that contained 7 to 10 ml of creamy, yellow pus. The abscess cavity occupied the space of the majority of the isthmus and the left lobe of the thyroid gland. Gram’s stain and culture failed to detect pathogens; no stain or culture for mycobacteria was performed. Histologic examina

Malignant epithelioid schwannoma of the skin: a low-grade neurotropic malignant melanoma?

We studied a polypoid cutaneous neoplasm excised from the left arm of a 23-year-old man by light microscopy, immunohistochemistry, and electron microscopy. Histologically, the tumor was composed of a proliferation of round to oval epithelioid cells that were arranged in fascicles and showed a prominent perineural distribution. Immunohistochemistry revealed the presence of S-100 protein and vimentin within tumor cells. Electron microscopy demonstrated reduplication of basal lamina and abundant long-spacing collagen in intercellular spaces. The findings are consistent with a primary malignant epithelioid schwannoma of the skin. We discuss the relationship of this lesion with other neoplasms in the spectrum of tumors showing schwannian and melanocytic lines of differentiation.

Subcutaneous fibroadenoma on an arm

A case of a subcutaneous fibroadenoma on an arm of an 18-year-old woman is presented. The neoplasm, thought clinically to be a lipoma, may have arisen in ectopic breast tissue. Dermatologists and dermatopathologists should be aware that fibroadenomas histologically identical with those seen in the breast have been observed along the milkline and may also occur in other sites.