Malignant eccrine hidradenoma.

Hidradenomas are adenomatous tumors of sweat gland origin that are usually benign and can occur in any cutaneous skin surface. When malignant, the tumors have high recurrence rates and are often fatal. Because of their infrequency and clinical ambiguity, hidradenomas are often misdiagnosed as other soft-tissue masses. Radiation and chemotherapy have not shown to be of benefit; therefore, wide aggressive excision and lymphadenectomy are currently the treatments of choice. We present the case of a patient with a malignant hidradenoma presenting in her medial heel. After excisional biopsy identified the tumor, the patient was successfully treated with wide excision and delayed closure via vacuum-assisted closure.

Derivation and characterization of an extra-axial chordoma cell line (EACH-1) from a scapular tumor.

BACKGROUND: Extra-axial chordomas are rare low-grade malignant tumors thought to arise from notochordal remnants in the extra-axial skeleton. Few studies have been done on this neoplasm because of its rarity. In addition, there is a lack of a good in vitro model on which to perform more characterization. METHODS: We describe a twenty-eight-year-old man with a mass in the right scapula. Cytomorphology and immunohistochemistry, including brachyury staining, were used to formulate the final diagnosis. A fragment of the tumor was placed in culture, and cells obtained were injected subcutaneously in an immunocompromised mouse. From the tumor developed in mice, a cell line has been derived and characterized by fluorescence-activated cell-sorting analysis, karyotyping, clonogenicity, and cell and tumor growth curves. RESULTS: Cytomorphology on the tumor showed nests of round cells with vacuoles and also physaliferous-like cells with uniform nuclei. Immunochemistry revealed a tumor positive for vimentin, moderately positive for S-100 and cytokeratin AE1/AE3, weakly positive for epithelial membrane antigen, and negative for p63 and cytokeratin (CK)-7. Further analysis revealed the tumor was diffusely and strongly positive for brachyury. The cell line derived from the tumor showed rapid doubling-time, a strong expression of mesenchymal cell surface markers, a karyotype of diploid or hypotetraploid clones with numerous chromosomal aberrations, and the ability to form colonies without attachment and to form tumors in immunocompromised mice. CONCLUSIONS: The diagnosis of the extra-axial chordoma is difficult but can be resolved by the detection of a strong brachyury expression. In addition, the derivation of a human extra-axial chordoma cell line could be a useful tool for the basic research of this rare neoplasm.

Infantile fibrosarcoma successfully treated with chemotherapy, with occurrence of calcifying aponeurotic fibroma and pleomorphic/spindled celled lipoma at the site 12 years later.

The treatment of infantile fibrosarcoma has traditionally been wide resection. Chemotherapy has been investigated as an adjuvant and primary treatment in cases in which surgery would cause unacceptable morbidity. Recurrences normally occur within a year of completion of the chemotherapy and display the same histology. We present a child with an infantile fibrosarcoma of the elbow, successfully treated with chemotherapy alone, who developed a calcifying aponeurotic fibroma and a spindle cell/pleomorphic lipoma at the tumor site 12 years later.

Massive osteolysis due to failure of a unipolar endoprosthesis.

Unipolar endoprostheses are commonly used for the treatment of displaced femoral neck fractures in the elderly. Failure due to polyethylene wear, which has been well documented in bipolar endoprostheses, is not a commonly reported problem with unipolar prostheses. We present 2 cases of a particular unipolar design that failed due to polyethylene wear. We report these cases to promote awareness of this particular reason for failure in this design. We also question the need for polyethylene in any prosthetic, when it is not indicated for the bearing surface.