Autopsy samples from eight former shipyard workers were collected from lung parenchyma, tracheal lymph nodes, and pleural plaques. The tissue from each respective area was prepared by a modified bleach digestion technique, and the residue was collected on a 0.2-micron pore polycarbonate or 0.22-micron mixed cellulose ester filter. Quantitation of ferruginous bodies and uncoated fibers was done by light and transmission electron microscopy, respectively. Differences in the asbestos burden were noted for each site. Ferruginous bodies were observed in both parenchyma and nodes but not in plaques. Three subjects were found to have more ferruginous bodies per gram dry weight in their lymph nodes than in their lung parenchyma. Likewise, all subjects were found to have more uncoated fibers per gram in the nodes than in the parenchyma. Amphibole and chrysotile fibers were noted in the lung and extrapulmonary sites, with chrysotile being the predominant asbestiform in plaques. The majority of the uncoated fibers in both the nodes and the plaques were less than or equal to 5 microns in length. However, some fibers with dimensions conforming to the "Stanton hypothesis" reached both areas. These residual patterns most likely reflect the impact of clearance on lung burden as opposed to the eventual accumulation and stasis in the extrapulmonary areas.

A series of 557 malignant mesotheliomas of the pleura diagnosed in the Trieste-Monfalcone area, Italy, in the period 1968-2000 were reviewed. The series included 492 men and 65 women, aged between 32 and 93 years (median age 69 years). Necropsy findings were available in 456 cases (82%). Occupational histories were obtained from the patients themselves or from their relatives by personal or telephone interviews. Routine lung sections were examined for asbestos bodies in 442 cases. In 109 cases isolation and counting of asbestos bodies were performed. A majority of people had histories of working in the shipyards. Asbestos bodies were observed in lung sections in 67% of the cases. Lung asbestos body burdens after isolation ranged between 20 bodies and about 10 millions of bodies/g dried tissue. Latency periods (time intervals between first exposure to asbestos and death) ranged between 14 and 75 years (mean 48.8 years, median 51.0). Latency periods among insulators and dock workers were shorter than among the other categories. High asbestos consumption occurred in many countries in the 1960s and in the 1970s. The data on latency periods obtained in the present study suggest that a world mesothelioma epidemic has to be expected in the coming decades.

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Background. Pleural mesothelioma is a rare condition with a poor prognosis. The area of Monfalcone, North East Italy, provided a unique opportunity to study the disease because of its past heavy exposure to asbestos in local harbors and shipyards and its high necropsy rates. Methods. The effects of various patient and tumor characteristics on survival were evaluated in 80 patients (73 males and 7 females; median age, 69) of histologically or cytologically confirmed malignant mesothelioma of the pleura. These patients were examined between October 1979 and October 1991 at the General Hospital of Monfalcone in the Friuli‐Venezia Giulia region. Substantial exposures to asbestos were identified in 79 patients. Results. Median survival rate was 13 months (range, 2–44 months), and overall 2‐ and 5‐year survival rates were 23% and 0%, respectively. The factors that exerted a significant favorable influence on survival were as follows: (1) age younger than 65; (2) performance status less than or equal to one; (3) lack of less than or equal to 10% weight loss at any time; (4) Stages I and II; (5) epithelial or mixed histologic type; and (6) presence of pleural fluid with mesothelial cells but without neoplastic cells. When these factors were introduced in a Cox proportional hazard model, age, stage, and histologic type were the only independent prognostic factors. The increased hazards for patients, ages 65–74 (as compared to < 65), and for patients with sarcomatous histologic type (as compared to epithelial type) were 2.6 (95% confidence interval [CI], 1.2–5.7) and 4.5 (95% CI, 1.6–12.8). Conclusions. Survival rate in 24 untreated patients (median, 10 months) and 56 patients variously treated (median, 15 months) did not differ significantly. The availability of large portions of tumor specimens for histologic examinations in 77 of 80 patients, chiefly from high necropsy rate, strengthens the value of the present analysis of prognostic factors.

The Monfalcone area, in northeastern Italy, is a small industrial temtory (population about 60,000), with a large shipyard. Between October 1979 and April 1992, ninety-two malignant mesotheliomas were diagnosed at the Monfalcone Hospital. The series included 84 men and 8 women, aged 42 to 89 years (median age 68 years). There were 89 pleural and 3 peritoneal tumors. Seventy patients (69 men and 1 woman) had worked in the shipyards; six were seamen, and four insulators. Five men had been exposed to asbestos in various industries; six women had histories of domestic exposure, and one woman had a history of possible environmental exposure. The latency periods (intervals between first exposure to asbestos and diagnosis of the tumor) ranged from 20 to 65 years (median 52 years). Latency periods among insulators were significantly lower than among shipyard workers, as well as lower than among the other categories (p