Laryngeal angiosarcoma: a clinicopathologic study of five cases with a review of the literature.

OBJECTIVE: Primary laryngeal angiosarcoma (LA) is rare without a reported series evaluating these tumors. STUDY DESIGN/METHODS: Five patients with LA were retrospectively retrieved from the Otorhinolaryngic Registry of the Armed Forces Institute of Pathology. RESULTS: Three men and 2 women, aged 29 to 71 years, presented with hoarseness (n = 4) and hemoptysis (n = 1). Two patients had previous neck radiation. The tumors involved the supraglottis (n = 4) with a mean size of 3.1 cm. Histologically, all tumors had anastomosing vascular channels lined by remarkably atypical endothelial cells protruding into the lumen, frequent atypical mitotic figures, and hemorrhage. All cases tested (n = 4) demonstrated immunoreactivity with antibodies to Factor VIII-RA and CD34. All patients had surgery followed by postoperative radiation (n = 3 patients). Three patients died with disease (mean, 17 mo), whereas one patient is alive with no evidence of disease at 18 years. CONCLUSIONS: LA is a rare tumor, frequently associated with previous radiation, usually involving the supraglottis with characteristic histomorphologic and immunophenotypic features. LA has a poor prognosis, making appropriate separation from other conditions important.

Increased susceptibility of male rats to kanamycin-induced cochleotoxicity.

Although clinical observations suggest that males are more susceptible than females to ototoxic drugs, controlled experimental studies investigating gender susceptibility have not been performed. Aminoglycosides initially attack the cochlea's outer hair cells (OHCs). We investigated the effects of the aminoglycoside, kanamycin, on electrophysiological function of OHCs in male and female rats. Animals were grouped by gender and treated with kanamycin (400 mg/kg/day kanamycin base, intramuscular injection) or equivolume normal saline. Administration was continued until distortion product otoacoustic emissions (DPOAEs) suggested a loss in OHC function in kanamycin-treated rats. Males treated with kanamycin showed changes in DPOAE thresholds and amplitudes as early as treatment day 10 which spread to all test frequencies by treatment day 13. In contrast, females treated with kanamycin did not show significant changes in thresholds or amplitudes until treatment day 22. The mechanism of increased male susceptibility to kanamycin cochleotoxicity has not been determined.

Hsp70 and Hsc70 are preferentially expressed in differentiated epithelial cells in normal human endometrium and ectocervix.

Two highly related 70K heat shock proteins, encoded by the hsc70 and hsp70 genes, are located in the nucleocytoplasmic compartment of mammalian cells. In contrast to recent cell lines, which express Hsp70 only when stressed, many human cell lines constitutively express Hsp70. The degree to which this reflects constitutive expression of Hsp70 in normal human tissues has not been extensively examined. In this study, we show by immunoblotting that human Hsp70 is constitutively expressed in the ovary, cervix, and endometrium and, by immunohistochemical analysis using Hsp70- and Hsc70-specific antibodies, that Hsp70 and Hsc70 are expressed in distinctive and predominantly overlapping patterns in the cervix and endometrium. In these two tissues, the highest levels of both proteins are seen in differentiated, non-proliferating epithelial cells, which is surprising in light of previous studies suggesting growth stimulation of hsp70 gene expression. These observations suggest the possibility that in certain human tissues, basal expression of the hsp70 and hsc70 genes is co-regulated.