Periaortic lymph node involvement by metastatic angiosarcoma and benign sinus mesothelial cells.

Hyperplastic mesothelial cells involving lymph node sinuses have only been recently described. Most nodal mesothelial cells are thought to originate from mesothelial surfaces disrupted by serosal effusions. Dislodged mesothelial cells likely gain access to submesothelial lymphatics via mesothelial stomata and disseminate to draining lymph nodes. Unusual lymph node architectural patterns result when benign sinus mesothelial cells occur concurrently with a neoplastic nodal process. We describe a young man who developed diffuse metastases from a primary cardiac angiosarcoma. His periaortic lymph nodes contained metastatic angiosarcoma and hyperplastic mesothelial cells with a sinus distribution. The patient had a clinical history of progressive haemoperitoneum, exacerbated by thrombocytopaenia and disseminated intravascular coagulation. Massive haemoperitoneum of 5000 ml was confirmed at autopsy. This is the first report to suggest that multiple episodes of intraperitoneal haemorrhage and ascites may both act in the same manner to cause dislodgment and dissemination of mesothelial cells to draining lymph node sinuses.

Neutrophils, nitric oxide synthase, and mutations in the mutatect murine tumor model.

Mutatect MN-11 is a tumor line that can be grown subcutaneously in syngeneic C57BL/6 mice. The frequency of spontaneously arising mutants at the hypoxanthine phosphoribosyltransferase (Hprt) locus was observed to be elevated as a result of in vivo growth. The objective of the present study was to identify factors in the tumor microenvironment that might explain this increase in mutant frequency (MF). When tumors were examined histologically, neutrophils were found to be the predominant infiltrating cell type. Quantitative estimates of the number of neutrophils and MF of tumors in different animals revealed a statistically significant correlation (r = 0.63, P < 0.0001). Immunohistochemical analysis for inducible nitric oxide synthase (iNOS) demonstrated its presence, mainly in neutrophils. Biochemical analysis of tumor homogenates for nitric oxide synthase (NOS) activity indicated a statistically significant correlation with MF (r = 0.77, P < 0.0001). Nitrotyrosine was detected throughout the tumor immunohistochemically; both cytoplasmic and nuclear staining was seen. To increase the number of infiltrating neutrophils, tumors were injected with chemoattractant interleukin-8 and prostaglandin E2. This produced a statistically significant increase in neutrophil content (P = 0.005) and MF (P = 0.0002). As in control MN-11 tumors, neutrophil content and MF were strongly correlated (r = 0.63, P = 0. 003). Because neutrophils are a potential source of genotoxic reactive oxygen and/or nitrogen species, our results support the notion that these tumor-infiltrating cells may be mutagenic and contribute to the burden of genetic abnormalities associated with tumor progression.

Pathological examination and the reporting of lung cancer specimens.

The Lung Cancer Disease Site Group (DSG) of the Cancer Care Ontario Practice Guidelines Initiative first met in January of 1994. Included in the membership were three pathologists who, with the other members of the DSG, felt that a useful contribution to the work of the group would be a recommendation on standardized examination and reporting of lung cancer specimens. This review summarizes the consensus of the Lung Cancer DSG pathologists based on their review of the literature and proposes a standard synoptic report, the Primary Lung Cancer Check-Off Sheet. If generally adopted, this standard would improve the quality of reporting of clinical and pathological stage information. Such high-quality staging information is essential to define patient populations for clinical trials and for outcome analyses.

Pathogenesis of soft-tissue contracture in club foot.

We investigated the pathogenesis of soft-tissue contracture in club foot, using immunohistochemistry to study 41 biopsy specimens and 12 normal deltoid ligaments from cadavers. Five biopsy specimens were studied by electron microscopy (EM) to determine the presence of myofibroblasts. All 41 specimens of club foot stained positively for vimentin as against only one of the 12 control specimens. By contrast, there was no difference in staining for desmin or alpha-smooth muscle actin. EM showed some variability in the appearance of ligamentous cells. Most contained bundles of microfilaments in the cytoplasm and many had abundant pinocytotic vesicles, but no basal lamina or plasmalemmal attachment plaques. Cells of the medial ligamentous tissue in patients with club foot contain vimentin and others have myofibroblastic characteristics. Both features may contribute to recurrence after soft-tissue release.

Octylcyanoacrylate tissue adhesive versus suture wound repair in a contaminated wound model.

BACKGROUND: Octylcyanoacrylate tissue adhesive is a topical wound closure that precludes the need for foreign bodies (sutures) to close wounds. It also has an in vitro antimicrobial effect when standard disc sensitivity tests are used. METHODS: To determine whether contaminated wounds closed with octylcyanoacrylate tissue adhesive will have a lower infection rate compared with wounds closed with 5-0 monofilament sutures, we designed a randomized, blinded, experimental animal study. Two incisions were made on 20 albino guinea pigs. The wounds were contaminated with 10(5) Staphylococcus aureus ATCC 12600 and randomly assigned to be closed with either topical octylcyanoacrylate tissue adhesive or percutaneous 5-0 polypropylene suture. Five days later the adhesive and sutures were removed, and a section of the wound was given to a histopathologist blinded to the type of wound closure. The wound was determined to be infected if inflammatory cells with intracellular cocci were seen. The rest of the wound was opened and examined for clinical evidence of infection. Quantitative bacteriologic analysis was performed. RESULTS: Five wounds in the tissue adhesive group were sterile on day 5, whereas all sutured wounds had positive cultures (25% versus 0%, p < 0.05). Fewer wounds in the tissue adhesive group were determined to be infected by histologic and clinical criteria (0% versus 55%, p < 0.001, and 20% versus 65%, p < 0.01, respectively). Agreement on the determination of infection by histologic and clinical criteria yielded a kappa coefficient of 0.46 (95% confidence interval [GI], 0.19 to 0.73). An infection criterion of 10(5) colony-forming units/gm of tissue correlated poorly with clinical and histologic infection rates (0.19 [95% CI, -0.06 to 0.44] and 0.13 [95% CI, -0.05 to 0.31], respectively). CONCLUSIONS: Contaminated wounds closed with sutures had higher infection rates compared with those reported with topical tissue adhesive. The amount of colonization may not be an accurate method to determine infection.

Bidirectional modulation of TNF-alpha production by alveolar macrophages in asbestos-induced pulmonary fibrosis.

Bronchoalveolar lavage (BAL) cells were isolated from rats 1, 3, and 6 weeks after a single intratracheal instillation of saline, UICC chrysotile asbestos (5 mg), or silica (5 mg). In asbestos-exposed rats, the pulmonary response was characterized by a significant increase in the number of alveolar macrophages (AMs) and the appearance of fibrotic lesions within 1 week. By contrast, mixed macrophage and neutrophil accumulations were observed in the silica group without evidence of fibrosis. Tumor necrosis factor-alpha (TNF-alpha) production by lipopolysaccharide (LPS)-stimulated BAL cells from asbestos-treated rats was significantly lower than controls 1 and 3 weeks after exposure. However, by 6 weeks higher levels of TNF-alpha production were noticeable in this group. Decreases in LPS-induced TNF-alpha production were also observed with BAL cells from silica-treated animals at all time points studied. Lower levels of TNF-alpha were not related to decreased BAL cell viability or the presence of a significant proportion of neutrophils in the silica group. Furthermore, biphasic changes in TNF-alpha production seen in the asbestos group were correlated with concomitant decreases (3 weeks) and increases (6 weeks) in levels of TNF-alpha mRNA in AMs. These data indicate that lower levels of TNF-alpha resulted from inhibition at the gene expression level and provide evidence for bidirectional modulation of TNF-alpha production by AMs during inflammatory reactions.

Cytomegalovirus infection of the female genital tract. Histologic findings in three cases and review of the literature.

Three cases of cytomegalovirus infection of the female genital tract, diagnosed on curettage, revealed a characteristic, although nonspecific histologic picture. This consisted of dense lymphocytic and plasma cell infiltrates with lymphoid follicles and signs of rapid cell turnover in the cervix when the latter was affected. The characteristic inclusions were very scant or even absent. The symptoms were not of diagnostic value.