Morphologic diversity in malignant melanoma: the potential use of microdissection and the polymerase chain reaction for diagnosis.

Malignant melanoma (MM) can mimic soft tissue (ST) and epithelial neoplasms. An immunoperoxidase (IP) panel and a morphologic comparison of the primary are used in diagnosis, which can be difficult when the morphologic and IP profiles of a metastatic lesion simulate those of an ST neoplasm. Through the comparison of known genetic abnormalities in primary and metastatic neoplasms, a definitive diagnosis can be suggested on the basis of the finding of identical allelic losses through the use of microdissection (MD) and the polymerase chain reaction (PCR). Genetic alterations involving the p16 gene on chromosome 9p21 have been observed in MM. We present the case of a 56-year-old man with known MM in whom multiple metastatic lesions to the skin and an adrenal gland developed during a 5-year period. A fine-needle aspiration (FNA) of a new ST buttock lesion was performed; the specimen had cytologic features different from those of the primary neoplasm and simulated a possible primary ST neoplasm. We attempted to make a definitive diagnosis of MM in the FNA of the ST buttock lesion through a genetic comparison with the primary neoplasm as well as with the other metastatic sites. Direct-visualization MD was performed on histologic glass slides of the primary and adjacent tissue (normal control), and the metastatic lesions, along with malignant cell clusters from the buttock lesion FNA. DNA was extracted and PCR amplified with primers D9S171 and IFNA for the p16 locus at the 9p21-22 region. Loss of heterozygosity for the D9S171 marker at the p16 gene locus was identified in all of the neoplastic tissue tested. Normal skin elements did not show deletion. The combination of MD and PCR are powerful tools that can be used for the comparison of genetic abnormalities in primary and metastatic neoplasms with unusual morphologic features to help support a diagnosis with a noncontributory IP.

Characteristics of nine newly derived mesothelioma cell lines.

This report characterizes nine new cell lines derived from patients with malignant pleural mesothelioma. The lines were initiated between July 1990 and July 1992 from solid tumors (5 lines) or effusions (4 lines) and had proliferated for a period of at least 2 months without senescence. They were characterized by cell size, doubling time, immunohistochemical analyses, electron microscopy, and chromosomal karyotyping. Growth factor/cytokine elaboration was determined using enzyme-linked immunoassays. The established lines were similar in morphology to their parent tumor (ie, epithelial or sarcomatoid). Cell sizes ranged from 59 to 81 microns, and the doubling times varied from 31 to 65 hours. The lines stained with cytokeratin and showed expected negative staining for adenomarkers including B72.3 and carcinoembryonic antigen. All cell lines exhibited aneuploidy, with modal chromosome numbers between 40 and 81 and had multiple chromosomal aberrations. Significant production of granulocyte-monocyte colony-stimulating factor, leukemia inhibitory factor, platelet-derived growth factor, and interleukin-6 was seen. These new cell lines derived from human mesotheliomas can now be used to aid in the design of innovative treatment strategies.

Cytology of extrapulmonary Pneumocystis carinii infection in the acquired immunodeficiency syndrome.

Rare cases of extrapulmonary Pneumocystis carinii (EPPC) have been seen in patients with acquired immunodeficiency syndrome (AIDS). We report seven such diagnoses of nonpulmonary P carinii (PC) from four AIDS patients between 1986 and 1989. The specimens included fine needle aspirate of liver, spleen, periarticular tissue and pleura as well as ankle fluid, pleural fluid and ascites. In some, but not all, cases the patients had concurrent or previous episodes of PC pneumonia. In all cases the typical granular, eosinophilic aggregates of PC cysts were noted on routine Papanicolaou staining, leading to the definitive detection of PC cysts with Grocott silver stain. In most cases, evidence for granulomalike and neovascularized tissue reaction was present in cytologic material. One specimen demonstrated concurrent acid fast bacilli. In the setting of AIDS, cytology of effusions and masses should include an evaluation for EPPC.

Apocrine mammary carcinoma. A clinicopathologic study of 72 cases.

Apocrine carcinoma (AC) is an uncommon, poorly characterized type of breast tumor. In this review, 55 patients with intraductal (ID) AC and 17 patients with infiltrating (IF) AC were analyzed retrospectively to define the histologic features and clinical course of this neoplasm. Recurrences in the breast occurred in 3 of 20 ID-AC patients treated by biopsy alone, but not in the 2 patients who received local radiation therapy after biopsy. One patient with ID-AC had axillary metastases at the time of treatment by mastectomy and died of disease five years later. The remaining patients with ID-AC treated by mastectomy have remained disease free. One of the three patients with IF-AC treated by biopsy alone died of disease, and one of two patients with IF-AC treated by biopsy and radiotherapy was alive with carcinoma. Twelve patients with IF-AC were treated by mastectomy. Ten of them were recurrence free at the time of last observation. More than one-third of the cases of ID-AC and IF-AC were detected by mammography alone. Survival analysis of IF-AC cases compared with nonapocrine duct carcinoma cases matched for stage revealed no statistical difference in estimated recurrence-free survival or estimated survival probability. AC is a distinct morphologic entity with a natural history similar to that of nonapocrine ductal carcinoma.

Metastatic thyroid carcinoma presenting as distal spinal cord compression.

The prognosis of metastatic thyroid carcinoma is dependent on the age of the patient, the histologic characteristics of the neoplasm, and the site of metastasis. A more favorable prognosis is found in patients less than 40 years old with follicular carcinoma and without any bony metastases. Metastatic thyroid carcinoma presenting as distal spinal cord compression is extremely rare. We report one such case and review the literature. As reported in the literature, the combination of decompressive laminectomy followed by total thyroidectomy and radioactive iodine therapy has proved to be effective in the treatment of patients with thyroid carcinoma metastatic to the distal vertebral bodies.

Lymphangioma presenting as a nasal polyp in an infant.

We describe a pedunculated lymphangioma presenting as an isolated nasal polyp in an 11-month-old male infant with light and electron microscopic findings. This lesion occurring in an infant must be distinguished from more common benign and malignant intranasal masses.