Mesothelioma: Sporn TA

Butnor KJ, Sporn TA, Ordonez NG, Anonymous00042. · Department of Pathology, University of Vermont, 111 Colchester Avenue, Burlington, VT 05401, USA. · Hum Pathol. · Pubmed #17276491 No free full text.

Abstract: It has been evident for decades that pathology reports are very variable even within a single institution. Standardization of reporting is the optimal way to ensure that information necessary for patient management, prognostic and predictive factor assessment, grading, staging, analysis of outcomes, and tumor registries is included in pathology reports. In recent years, 2 societies (first the Association of Directors of Anatomic and Surgical Pathology [ADASP] and then the College of American Pathologists [CAP]) have undertaken to publish guidelines for the reporting of common cancers. The CAP assigned multidisciplinary groups of pathologists, surgeons, radiation, and medical oncologists to develop the protocols. Other pathologists and clinicians then reviewed them. After those reviews the protocols were reviewed by multiple CAP committees and finally approved by the Board of Governors. The ADASP, in contrast, chose a pathologist expert in each filed to assemble a group from within the pathology community (with clinician input if desired) to write specific cancer protocols. These were then approved by the ADASP council and subsequently by the membership. Although both societies began the process at approximately the same time, the streamlined approach adopted by the ADASP enabled them to publish years earlier in pathology journals frequented by anatomic pathologists. Although the formats are somewhat different, the contents are essentially the same. The American College of Surgery Commission on Cancer (COC) accredits cancer centers in the United States. Recently, the COC decided to require elements, deemed as essential by the CAP, to be described in all pathology reports in their accredited cancer centers as of January 2004. Importantly, they do not require that the specific CAP protocols or synoptic reports be used. The ADASP has updated all of its protocols to comply with the COC requirements in the form of 37 uniform checklists. The checklists use the staging criteria sited in the American Joint Committee on Cancer 2002 Staging Manual (sixth edition) but include a variety of other references listed in each of the checklists. Moreover, the checklists are formatted for ease of use. They may be used as templates for uniform reporting and are designed to be compatible with voice-activated transcription. The different elements in these revised ADASP diagnostic checklists have been divided into required and optional. The term required in this context only signifies compliance with the COC guidelines. The ADASP realizes that specimens and practices vary, and it will not be possible to report these elements in every case. However, the ADASP hopes that pathologists will find these checklists to be useful in daily clinical practice, while facilitating compliance with the new COC requirements.

Butnor KJ, Burchette JL, Sporn TA, Hammar SP, Roggli VL. · Department of Pathology, University of Vermont, Burlington, VT, USA. · Arch Pathol Lab Med. · Pubmed #15086281 No free full text.

Abstract: CONTEXT: The development of successful chemotherapeutic agents directed against the Kit receptor tyrosine kinase protein has generated intense interest in the Kit (CD117) immunoreactivity of various neoplasms. Immunoreactivity for Kit in small cell lung carcinoma (SCLC) has been well established. However, data on Kit immunostaining in other lung tumors is limited. Likewise, while solitary fibrous tumors of the gastrointestinal tract have been examined for Kit expression, the Kit staining characteristics of their counterpart in the pleura, namely, localized fibrous tumor, are not well known. OBJECTIVE: To characterize the Kit immunohistochemical profiles of major types of lung and pleural tumors. DESIGN: We stained 60 lung carcinomas, including 11 SCLCs, 4 large cell neuroendocrine carcinomas, 22 squamous cell carcinomas, 23 adenocarcinomas, 11 pulmonary carcinoid tumors, 19 pleural malignant mesotheliomas, and 6 localized pleural fibrous tumors with a commonly used polyclonal Kit antibody. RESULTS: Small cell lung carcinomas demonstrated Kit staining in 82% of cases, nearly all of which demonstrated moderate to intense immunoreactivity. Immunostaining was observed in 25% of large cell neuroendocrine carcinomas. Focal staining was observed in 9% of squamous cell carcinomas and 17% of adenocarcinomas. None of the pulmonary carcinoid tumors were immunoreactive. Moderately intense immunostaining was present in 50% of localized fibrous tumors. Malignant mesotheliomas were nonimmunoreactive for Kit in 95% of cases. CONCLUSION: Non-small cell lung carcinomas showed very limited expression of Kit. Lung tumors with neuroendocrine differentiation exhibited a wide spectrum of Kit immunoreactivity, ranging from rare in pulmonary carcinoid tumors to frequent in SCLC. The high frequency of Kit immunostaining in SCLC has important potential therapeutic implications. Demonstration of Kit positivity in some localized fibrous tumors in this study contrasts with absent immunoreactivity in solitary fibrous tumors of the gastrointestinal tract. The paucity of Kit staining in malignant mesothelioma suggests these tumors are unlikely to respond to currently available tyrosine kinase inhibitors.

Schneider F, Sporn TA, Roggli VL. · Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, USA. · Ultrastruct Pathol. · Pubmed #18958788 No free full text.

Abstract: This study reports changes in the frequency of detection of various asbestos fiber types between 1982 and 2005. Crocidolite is increasingly detected in U.S. mesothelioma patients. The percentage of crocidolite fibers detected in lung tissue has risen from 4 to 10%, and the percentage of cases in which crocidolite was detected increased from 19 to 37%. Meanwhile, the frequency of detection of amosite and chrysotile has decreased. The authors performed a detailed analysis of cases in which crocidolite was identified in the absence of amosite. Most of such cases were identified in recent years, a finding of concern since crocidolite is considered the most potent fiber type with respect to the pathogenesis of mesothelioma.

Butnor KJ, Sporn TA, Ordonez NG, Anonymous00079. · Department of Pathology, University of Vermont, Burlington, VT, USA. · Virchows Arch. · Pubmed #17334801 No free full text.

This publication has no abstract.

Schneider F, Volmar KE, Sporn TA. · Technische Universitat Munchen, Munich, Germany. · Arch Pathol Lab Med. · Pubmed #14692825 No free full text.

This publication has no abstract.

Butnor KJ, Sporn TA, Roggli VL. · University of Vermont Medical Center, Department of Pathology, Burlington, VT 05405, USA. · Ann Occup Hyg. · Pubmed #12765873 links to  free full text

Abstract: OBJECTIVES: A large number of workers in the USA are exposed to chrysotile asbestos through brake repair, yet only a few cases of malignant mesothelioma (MM) have been described in this population. Epidemiologic and industrial hygiene studies have failed to demonstrate an increased risk of MM in brake workers. We present our experience of MM in individuals whose only known asbestos exposure was to brake dust and correlate these findings with lung asbestos fiber burdens. METHODS: Consultation files of one of the authors were reviewed for cases of MM in which brake dust was the only known asbestos exposure. Lung fiber analyses were performed using scanning electron microscopy (SEM) in all cases for which formalin-fixed or paraffin-embedded lung tissue was available. RESULTS: Ten cases of MM in brake dust-exposed individuals were males aged 51-73 yr. Nine cases arose in the pleura and one in the peritoneum. Although the median lung asbestos body count (19 AB/g) is at our upper limit of normal (range 0-20 AB/g), half of the cases had levels within our normal range. In every case with elevated asbestos fiber levels by SEM, excess commercial amphibole fibers were also detected. Elevated levels of chrysotile and non-commercial amphibole fibers were detected only in cases that also had increased commercial amphibole fibers. CONCLUSIONS: Brake dust contains exceedingly low levels of respirable chrysotile, much of which consists of short fibers subject to rapid pulmonary clearance. Elevated lung levels of commercial amphiboles in some brake workers suggest that unrecognized exposure to these fibers plays a critical role in the development of MM.

Roggli VL, Vollmer RT, Butnor KJ, Sporn TA. · Department of Pathology, Duke University and Durham VA Medical Centers, NC 27710, USA. · Ann Occup Hyg. · Pubmed #12176759 links to  free full text

Abstract: BACKGROUND: Exposure to chrysotile dust has been associated with the development of mesothelioma and recent studies have implicated contaminating tremolite fibers as the likely etiological factor. Tremolite also contaminates talc, the most common non-asbestos mineral fiber in our control cases. METHODS: We examined 312 cases of mesothelioma for which fiber burden analyses of lung parenchyma had been performed by means of scanning electron microscopy to determine the content of tremolite, non-commercial amphiboles, talc and chrysotile. The vast majority of these patients were exposed to dust from products containing asbestos. RESULTS: Tremolite was identified in 166 of 312 cases (53%) and was increased above background levels in 81 cases (26%). Fibrous talc was identified in 193 cases (62%) and correlated strongly with the tremolite content (P < 0.0001). Chrysotile was identified in only 32 cases (10%), but still correlated strongly with the tremolite content (P < 0.0001). Talc levels explained less of the tremolite deviance for cases with an increased tremolite level than for cases with a normal range tremolite level (22 versus 42%). In 14 cases (4.5%) non-commercial amphibole fibers (tremolite, actinolite and/or anthophyllite) were the only fiber types found above background. CONCLUSIONS: We conclude that tremolite in lung tissue samples from mesothelioma victims derives from both talc and chrysotile and that tremolite accounts for a considerable fraction of the excess fiber burden in end-users of asbestos products.

Butnor KJ, Sporn TA, Hammar SP, Roggli VL. · Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, USA. · Am J Surg Pathol. · Pubmed #11688466 No free full text.

Abstract: Well-differentiated papillary mesothelioma is an unusual variant of epithelial mesothelioma considered to be of low malignant potential. The majority of previously reported cases developed in the peritoneum of young women without a history of asbestos exposure. The authors report 14 cases of well-differentiated papillary mesothelioma, seven of which originated in the pleura, six in the peritoneum, and one in the tunica vaginalis. Eleven of the patients were male and three were female, with an average age at presentation of 58 years (range 32-82 years). Six of the patients had a quantifiable history of asbestos exposure. Of the nine cases with complete follow-up, six had clinically indolent disease, one showed resolution after adjuvant chemotherapy, one pursued an aggressive course, and one died of other causes. These findings indicate that well-differentiated papillary mesothelioma is a rare variant of mesothelioma with a variable clinical prognosis that is etiologically related to asbestos exposure in some cases.

Crotty EJ, McAdams HP, Erasmus JJ, Sporn TA, Roggli VL. · Department of Radiology, Box 3808, Duke University Medical Center, Durham, NC 27710, USA. · AJR Am J Roentgenol. · Pubmed #11090371 links to  free full text

Abstract: OBJECTIVE: The purpose of our study was to describe the clinical and radiologic features of epithelioid hemangioendothelioma of the pleura. CONCLUSION: Pleural epithelioid hemangioendothelioma is an uncommon malignancy that typically affects older men, who present with chest pain and dyspnea. This lesion manifests on chest radiographs and CT scans with unilateral pleural fluid and nodular pleural thickening and appears similar to diffuse pleural carcinomatosis or mesothelioma.

Stamat JC, Chekan EG, Ali A, Ko A, Sporn TA, Eubanks WS. · Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA. · J Laparoendosc Adv Surg Tech A. · Pubmed #10522541 No free full text.

Abstract: Malignant mesothelioma is a well-recognized long-term sequela of chronic asbestos exposure. Asbestos use in the United States began in the 1950s and was widespread until the mid-1970s. Although currently only 2.2 cases per million population per year are diagnosed, disease incidence is increasing because of the long latency of this neoplasm. A latency of 15-50 years means that a higher incidence of this neoplasm can be anticipated in the future. The authors report a patient with peritoneal mesothelioma and no known prior exposure to asbestos. The diagnosis was confirmed by exploratory laparoscopy, which entailed biopsies of the diaphragm and of the peritoneal and abdominal walls, and by cytologic evaluation of 700 ml ascitis fluid. At present, exploratory laparoscopy offers the quickest, safest, and least invasive way to confirm the clinical diagnosis of peritoneal malignant mesothelioma.