Leiomyosarcoma of the broad ligament. A case report and literature review with follow-up.

A case of leiomyosarcoma arising in a preexisting leiomyoma of the broad ligament is presented with ultrastructural and Feulgen microspectrophotometric confirmation. This is the fourth reported case of leiomyosarcoma of the broad ligament and the second reported case to show evidence of a preexisting leiomyoma. Three of these patients died after intervals of 1, 7, and 19 months; one is alive and well with no evidence of disease after 12 years. The definitive evidence of malignant transformation of a leiomyoma has particular relevance to the controversy regarding the relationship of uterine leiomyosarcomas and leiomyomas.

Primary leptomeningeal melanoma: an ultrastructural study.

A primary leptomeningeal melanoma in a 19-year-old white women has been shown by electron microscopy to contain light and dark cells. The light cells fill the subarachnoid space, contain mature melanosomes and exhibit intracytoplasmic fine fibrils. The dark cells are found within the collagen network of pia-arachnoid. They possess a small rim of ribosomal-rich cytoplasms, occasional premelanosomes and no intracytoplasmic fibrils. The tumor cells appear to arise from these dark activated melanoblasts in the pia-arachnoid and proliferate into more differentiated light cells. A similar pattern of two types of cells has not been described in primary CNS melanomas. The possibility of differentiation from cutaneous melanoma is discussed.

Primary pigmented carcinoma of the choroid plexus. A light and electron microscopic study.

Pigmented carcinoma of the choroid plexus was found in a 33-year-old man. Autopsy revealed no primary tumor in the skin or eyes. A slightly cystic pigmented tumor was present in the right lateral ventricle infiltrating the thalamus and striatum. Metastatic implants were found in both temporal lobes and the cerebellum. The spinal cord was covered by black meningeal nodules, and the cauda equina was completely encased by the tumor. Metastases were found in the liver, pancreas, and kidney. Microscopically the mass contained normal choroid plexus with psammoma bodies adjacent to carcinomatous epithelium forming prominent papillae and tubules. Melanin granules were found within the neoplastic cells and in the stroma. Electron microscopy demonstrated melanin granules in various stages of development in the cells, which were joined one to another by desmosome-like structures. This is the second reported case of pigmented carcinoma of the choroid plexus and the first with metastases outside the central nervous system.

Whipple's disease of the central nervous system.

Whipple's disease presenting as a neurological disease without gastrointestinal symptoms is an unusual occurrence. A 40 year old man suffered hypersomnia, memory loss and progressive ophthalmoplegia for 6 months prior to death. The nature of this disease was not established during life. Extensive granulomatous inflammation affecting the hypothalamus, hippocampus and periaqueductal gray matter of the brain was found to represent Whipple's disease by electron microscopy. Characteristic lesions were also present in spleen, mesenteric lymph nodes, small intestine and myocardium. Bacillary bodies and membranous inclusions similar to those seen in visceral lesions of Whipple's disease were present in macrophages. The findings supported the theory of direct involvement of the central nervous system by bacilli rather than a metabolic origin for the lesions.

Maturational arrest of fetal muscle in neonatal myotonic dystrophy. A pathologic study of four cases.

Skeletal muscles from four infants with a severe neonatal form of myotonic muscular dystrophy showed histopathologic features of immaturity. Three of the infants died in the neonatal period and were studied at autopsy; one of these and the still-living infant had a gastrocnemius muscle biopsy. The most severely involved muscles were those associated with arthrogrypotic joints regardless of function as flexors or extensors. Pharyngeal muscles and the diaphragm were also severely involved. Immature features included irregularly distributed small, round muscles fibers with large vesicular internal nuclei and sparse myofibrils. Histochemical differentiation was incomplete and fiber types often could not be distinguished. Muscle fiber degeneration and other features of myotonic dystrophy in adult muscle were lacking. Electron microscopy showed fine granular chromatin and convoluted nuclear membranes of centronuclear fibers, dialated transvers tubules that were aligned longitudinally as in fetal myotubes, poorly formed Z-bands, simple mitochondria, and many satellite cells. We suggest that these features represent an arrest in fetal muscle maturation due to unresponsiveness of an abnormal sarcolemma to trophic influences of normal innervation.