The concept of mesothelioma in situ, with consideration of its potential impact on cytology diagnosis.

Diffuse malignant mesothelioma (MM) is an incurable tumour of the serosal membranes, which is often caused by exposure to asbestos and commonly diagnosed at advanced stage. Malignant mesothelioma in situ (MMIS) is now included as diagnostic category by the World Health Organization (WHO). However, our international survey of 34 pulmonary pathologists with an interest in MM diagnosis highlights inconsistency regarding how the diagnosis is being made by experts, despite published guidelines. Whilst the WHO restricts the diagnosis to surgical samples, the very concept has implication for cytological diagnosis, which is already regarded as controversial in itself by some. MMIS is currently only applicable as precursor to MM with an epithelioid component, and raises the possibility for different molecular pathways for different histological MM subtypes. The clinical implications of MMIS at this stage are uncertain, but aggressive therapies are being initiated in some instances. Based on the results of the survey we here present a critical appraisal of the concept, its clinical and conceptual implications and provide practice suggestions for diagnosis. A low threshold for ancillary testing is suggested. The designations of 'malignant mesothelioma, cannot exclude MMIS' or 'atypical mesothelial proliferation with molecular indicators of malignancy, so-called MMIS' could be used on cytology samples, adding 'no evidence of invasion in sample provided' for surgical samples. Clinical and radiological correlation are integral to diagnosis and best done at multidisciplinary meetings. Finally, collaborative studies are required to improve our understanding of MMIS.

Comparison of outcomes following a cytological or histological diagnosis of malignant mesothelioma.

BACKGROUND: Survival with the epithelioid subtype of malignant mesothelioma (MM) is longer than the biphasic or sarcomatoid subtypes. There is concern that cytology-diagnosed epithelioid MM may underdiagnose the biphasic subtype. This study examines survival differences between patients with epithelioid MM diagnosed by cytology only and other subtypes diagnosed by histology. METHODS: Demographics, diagnosis method, MM subtype and survival were extracted from the Western Australia (WA) Mesothelioma Registry, which records details of all MM cases occurring in WA. RESULTS: A total of 2024 MM cases were identified over 42 years. One thousand seven hundred forty-four (86.2%) were male, median (IQR) age was 68.6 (60.4-77.0) years. A total of 1212 (59.9%) cases were identified as epithelioid subtype of which 499 (41.2%) were diagnosed using fluid cytology only. Those with a cytology-only diagnosis were older than the histology group (median 70.2 vs 67.6 years, P<0.001), but median survival was similar (cytology 10.6 (5.5-19.2) vs histology 11.1 (4.8-19.8) months, P=0.727) and Cox regression modelling adjusting for age, sex, site and time since first exposure showed no difference in survival between the different diagnostic approaches. CONCLUSIONS: Survival of cytologically and histologically diagnosed epithelioid MM cases does not differ. A diagnostic tap should be considered adequate to diagnose epithelioid MM without need for further invasive testing.

Histopathology of removed indwelling pleural catheters from patients with malignant pleural diseases.

BACKGROUND AND OBJECTIVE: Indwelling pleural catheters (IPC), used for management of malignant pleural effusions, are often left in situ for a long duration. This study reports for the first time the histological findings of IPCs removed from patients with underlying pleural malignancy. METHODS: Forty-one IPCs (in situ for median 126 days, interquartile range 43-226) that were removed over a 54-month period from a single centre were examined. RESULTS: Mesothelioma (n = 18) was the predominant underlying malignancy followed by breast, tubo-ovarian and lung carcinomas. The catheter tubing was fully intact macroscopically in all IPCs. There was no evidence of direct tumour invasion or cancer cell growth on the catheter surfaces in none of the 29 IPCs that were histologically examined. Malignant cells were seen within organizing fibrinous tissues in the lumen of 11 IPCs (27%). A foreign body giant cell reaction was present at the cuff site in all the 29 IPC in which the subcutaneous cuff was examined. Acute (n = 10) and/or chronic inflammatory changes were seen in the luminal contents in all 41 IPCs. CONCLUSION: Our study provides reassuring evidence that the IPC material does not support direct tumour growth or invasion even in the setting of high mesothelioma prevalence. See Editorial, page 787.

A Novel Clinical Prediction Model for Prognosis in Malignant Pleural Mesothelioma Using Decision Tree Analysis.

INTRODUCTION: Malignant pleural mesothelioma (MPM) is a rare cancer with a heterogeneous prognosis. Prognostic models are not widely utilized clinically. Classification and regression tree (CART) analysis examines the interaction of multiple variables with a given outcome. METHODS: Between 2005 and 2014, all cases with pathologically confirmed MPM had routinely available histological, clinical, and laboratory characteristics recorded. Classification and regression tree analysis was performed using 29 variables with 18-month survival as the dependent variable. Risk groups were refined according to survival and clinical characteristics. The model was then tested on an external international cohort. RESULTS: A total of 482 cases were included in the derivation cohort; the median survival was 12.6 months, and the median age was 69 years. The model defined four risk groups with clear survival differences (p < 0.0001). The strongest predictive variable was the presence of weight loss. The group with the best survival at 18 months (86.7% alive, median survival 34.0 months, termed risk group 1) had no weight loss, a hemoglobin level greater than 153 g/L, and a serum albumin level greater than 43 g/L. The group with the worst survival (0% alive, median survival 7.5 months, termed risk group 4d) had weight loss, a performance score of 0 or 1, and sarcomatoid histological characteristics. The C-statistic for the model was 0.761, and the sensitivity was 94.5%. Validation on 174 external cases confirmed the model's ability to discriminate between risk groups in an alternative data set with fair performance (C-statistic 0.68). CONCLUSIONS: We have developed and validated a simple, clinically relevant model to reliably discriminate patients at high and lower risk of death using routinely available variables from the time of diagnosis in unselected populations of patients with MPM.

Guidelines for cytopathologic diagnosis of epithelioid and mixed type malignant mesothelioma. Complementary statement from the International Mesothelioma Interest Group, also endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology.

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma (MM). Cytopathologists involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC), who have an interest in the field contributed to this update. Reference material includes peer-reviewed publications and textbooks. This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists, who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in cape town. During the previous IMIG biennial meetings, thorough discussions have resulted in published guidelines for the pathologic diagnosis of MM. However, previous recommendations have stated that the diagnosis of MM should be based on histological material only.[12] Accumulating evidence now indicates that the cytological diagnosis of MM supported by ancillary techniques is as reliable as that based on histopathology, although the sensitivity with cytology may be somewhat lower.[345] Recognizing that noninvasive diagnostic modalities benefit both the patient and the health system, future recommendations should include cytology as an accepted method for the diagnosis of this malignancy.[67] The article describes the consensus of opinions of the authors on how cytology together with ancillary testing can be used to establish a reliable diagnosis of MM.

Characterization of hypoxia in malignant pleural mesothelioma with FMISO PET-CT.

OBJECTIVES: Malignant pleural mesothelioma (MPM) is a chemotherapy resistant tumor with a poor prognosis. Hypoxia is increasingly recognized as an important factor in tumor aggressiveness and cellular resistance to chemotherapy and radiation treatment. This prospective pilot study was performed with [F-18] fluoromisonidazole (FMISO) PET-CT to characterize hypoxia in patients with MPM. MATERIALS AND METHODS: Twenty prospectively recruited patients with histologically or cytologically confirmed MPM not currently receiving systemic or local treatment underwent both FMISO and fluorodeoxyglucose (FDG) PET-CT scans within 2 weeks. FMISO and FDG PET-CT scans were independently analyzed visually and semi-quantitatively using SUVmax and tumor to background ratio (TBR) in order to assess tumor hypoxia and metabolic activity. Lesion by lesion analysis was performed in sites of measurable pleural masses. RESULTS: Visual analysis demonstrated tumor FMISO activity in 17 of 20 patients, and tumor FDG activity in 19 of 20 patients. Focal areas of bulky tumor were most likely to demonstrate hypoxia. In 19 patients suitable for semi-quantitative analysis the median FDG SUVmax was 6.4 (range 1.9-19.1), median FMISO SUVmax was 2.5 (range 1.4-3.7) and median FMISO TBR was 1.8 (1.1-2.5). There was a positive correlation between intensity of metabolic activity and hypoxia (r=0.72, p=0.001). Lesion by lesion analysis demonstrated a positive correlation between tumor thickness and FMISO activity (r=0.77, p<0.001). CONCLUSION: This pilot study confirms that MPM is a tumor with significant areas of hypoxia, particularly in dominant tumor masses. The relationship of tumor hypoxia to effectiveness of chemotherapy and/or radiation therapy warrants prospective assessment.

Guidelines for the cytopathologic diagnosis of epithelioid and mixed-type malignant mesothelioma: Complementary Statement from the International Mesothelioma Interest Group, Also Endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology.

OBJECTIVE: To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma. DATA SOURCES: Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks. RATIONALE: This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

Guidelines for the cytopathologic diagnosis of epithelioid and mixed-type malignant mesothelioma. Complementary statement from the International Mesothelioma Interest Group, also endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology.

OBJECTIVE: To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma. DATA SOURCES: Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks. RATIONALE: This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

Pleural fluid mesothelin as an adjunct to the diagnosis of pleural malignant mesothelioma.

RATIONALE: The diagnosis of pleural malignant mesothelioma (MM) by effusion cytology may be difficult and is currently controversial. Effusion mesothelin levels are increased in patients with MM but the clinical role of this test is uncertain. OBJECTIVES: To determine the clinical value of measuring mesothelin levels in pleural effusion supernatant to aid diagnosis of MM. METHODS AND MEASUREMENTS: Pleural effusion samples were collected prospectively from 1331 consecutive patients. Mesothelin levels were determined by commercial ELISA in effusions and their relationship to concurrent pathology reporting and final clinical diagnosis was determined. RESULTS: 2156 pleural effusion samples from 1331 individuals were analysed. The final clinical diagnosis was 183 MM, 436 non-MM malignancy, and 712 nonmalignant effusions. Effusion mesothelin had a sensitivity of 67% for MM at 95% specificity. Mesothelin was elevated in over 47% of MM cases in effusions obtained before definitive diagnosis of MM was established. In the setting of inconclusive effusion cytology, effusion mesothelin had a positive predictive value of 79% for MM and 94% for malignancy. CONCLUSIONS: A mesothelin-positive pleural effusion, irrespective of the identification of malignant cells, indicates the likely presence of malignancy and adds weight to the clinical rationale for further investigation to establish a malignant diagnosis.

A commercially available preparation of Staphylococcus aureus bio-products potently inhibits tumour growth in a murine model of mesothelioma.

BACKGROUND AND OBJECTIVE: Mesothelioma is an incurable cancer with a rising global incidence. Intrapleural delivery of a commercially available compound made up of proteins produced by Staphylococcus aureus has been used clinically to induce pleurodesis. We investigate if this bacterial compound has anti-tumoural activities against pleural malignancies, in addition to its pleurodesing effect. METHODS: The effects of the treatment on mesothelioma cells were evaluated in vitro and further tested in two validated murine models. RESULTS: This S. aureus bio-product mixture effectively kills mesothelioma cells and induces the release of interleukin (IL)-8, monocyte chemotactic protein (MCP)-1 and vascular endothelial growth factor from primary human mesothelial cells but not malignant pleural mesothelioma cells in vitro. Intratumoural delivery of the treatment in BALB/c mice induced tumour necrosis and local activation of T cells. Tumour growth was significantly inhibited in the treatment group during and after the treatment period (size of tumour 58.8 ± 10.3 mm(2) vs 118.3 ± 6.7 mm(2) from saline controls at day 23, n = 9-12 per group), P < 0.001. Tumour growth resumed on cessation of treatment, confirming the inhibition was treatment related. Treatment benefits were further validated in an orthotopic peritoneal model of mesothelioma and the compound significantly reduced the mesothelioma load (P < 0.05 vs saline controls). Mice in the treatment group had a significant increase in the percentage of activated CD4(+) and CD8(+) T cells in tumour-draining lymph nodes. No histological side-effects were observed with the treatment. CONCLUSIONS: This proof-of-principle study demonstrates promising antitumoural activity of a commercially available compound of S. aureus bio-products against mesothelioma.

Comparison of fibulin-3 and mesothelin as markers in malignant mesothelioma.

BACKGROUND: Pleural malignant mesothelioma (MM) is a deadly tumour predominantly associated with asbestos exposure. A reliable diagnostic and prognostic marker for MM will significantly enhance clinical care and is an area of intense research. Soluble mesothelin is the most studied and an FDA-approved biomarker for MM. A recent report showed promising results using fibulin-3 as a new diagnostic marker. The aim of this study was to compare the utility of fibulin-3 versus mesothelin, singly or in combination. METHODS: Fibulin-3 and soluble mesothelin were determined by ELISA in the plasma and pleural fluid of 153 patients presenting with a pleural effusion including 82 with MM, 36 with non-MM malignant effusions and 35 with benign effusions. Biomarker concentrations were determined in the plasma of an additional 49 cases with benign asbestos-related disease. RESULTS: Mesothelin provides better diagnostic accuracy than fibulin-3 for MM whether measured in plasma or pleural effusion: area under the curve (AUC) for plasma was 0.822 (95% CI 0.76 to 0.87) compared with 0.671 (0.61 to 0.73), respectively, and for pleural fluid AUC was 0.815 (0.74 to 0.87) compared with 0.588 (0.51 to 0.67), respectively. Effusion fibulin-3 was an independent significant prognostic factor for survival in MM patients; HR 2.08 (1.14 to 3.82), p=0.017. MM patients with effusion fibulin-3 levels below the median survived significantly longer than those with levels above the median (14.1 vs 7.9 months, p=0.012). Mesothelin and neutrophil to lymphocyte ratio were not significant prognostic markers. CONCLUSIONS: Soluble mesothelin is a superior diagnostic biomarker for MM compared with fibulin-3, whereas fibulin-3 provides superior prognostic information compared with mesothelin.

Pleural effusion hyaluronic acid as a prognostic marker in pleural malignant mesothelioma.

BACKGROUND: Malignant mesothelioma (MM), a primarily asbestos-induced tumour, has a poor prognosis, with over-all 5-year survival less than 5%. Tumour biomarkers are being intensely investigated in MM as aids to diagnosis and prognosis. Hyaluronic acid (HA) is produced in MM but its role in prognostication remains uncertain. MATERIALS AND METHODS: HA concentrations were determined in matching serum and pleural effusion of 96 MM patients, 26 lung cancer patients and 42 patients with benign effusions resulting from infectious, cardiac, renal, liver and rheumatoid diseases and compared to the current 'best practice' biomarker, mesothelin. Liver and kidney function were determined for each patient. Diagnostic accuracy was determined by area under the receiver operator characteristic curve (AUC) analysis following logistic regression modelling. Difference in survival between groups was determined by both log-rank test and Cox proportional hazards regression modelling. RESULTS: For effusion HA, the AUC (IQ range) was 0.89 (0.82-0.94) and for effusion mesothelin, it was 0.85 (0.78-0.90). Serum HA was not diagnostically useful. A combined measure of effusion HA, and serum and effusion mesothelin had an AUC of 0.92 (0.86-0.96), which was significantly higher than effusion mesothelin alone. Effusion HA had a biphasic distribution in MM patients, dichotomised at a concentration of 75 mg/L. The median survival of MM patients with high effusion HA was 18.0 (13.7-22.4) months, significantly longer than those with low HA effusion levels (12.6 months (8.4-16.8), p=0.004). Serum HA, and effusion and serum mesothelin were not significant prognostic indicators. CONCLUSION: This study demonstrates that a combined biomarker panel has greater diagnostic accuracy than effusion mesothelin alone, and that significant prognostic information is provided by effusion HA.

A diagnosis of malignant pleural mesothelioma can be made by effusion cytology: results of a 20 year audit.

AIMS: Cytological diagnosis of malignant pleural mesothelioma (MPM) is controversial, but has been used in our institution for over 30 years. To assess the role of effusion cytology in mesothelioma diagnosis we conducted an audit of pleural fluid cytology results over a 20 year period (1988-2007). METHODS: Pleural samples were received from 6285 patients; data linkage with Western Australian Cancer and Mesothelioma Registries demonstrated that 815 of these patients had a diagnosis of MPM. Cytological examination of a pleural effusion specimen had been performed in 517 (63%) of these 815 patients. RESULTS: Definitive cytological diagnosis of MPM was made in 377/517 cases, resulting in an 'absolute' sensitivity of 73%. An additional 66 patients were diagnosed as atypical/suspicious, resulting in a 'complete' sensitivity of 86%. If only biopsy/necropsy proven cases are considered, the absolute sensitivity is 68% and the complete sensitivity is 82%. There were no false positive diagnoses of malignancy; two patients with metastatic adenocarcinoma were initially diagnosed as MPM, prior to the availability of specific mesothelial markers, resulting in a positive predictive value of 99%. CONCLUSIONS: Effusion cytology is an inexpensive, minimally invasive procedure which should be included in the diagnostic work-up of cases of suspected MPM.

A phase II study of intermittent sunitinib malate as second-line therapy in progressive malignant pleural mesothelioma.

INTRODUCTION: There is no accepted second-line therapy for patients with advanced malignant pleural mesothelioma (MPM), whose disease has progressed after first-line chemotherapy. The multitargeted tyrosine kinase inhibitor sunitinib malate targets several pathways overexpressed in mesothelioma. This phase II study assessed objective response to sunitinib and correlative biomarkers in patients with progressive pretreated MPM. METHODS: Eligible patients had confirmed MPM, radiological progression after chemotherapy, Eastern Cooperative Oncology Group performance status 0 to 1, and measurable disease. Patients received oral sunitinib 50 mg daily for 28 of every 42 days. The primary endpoint was objective radiological response. Patients without prior pleurodesis had fluorodeoxyglucose positron emission tomographic response assessed by total glycolytic volume criteria. Correlative biomarkers included serum mesothelin, vascular endothelial growth factor (VEGF)-A, VEGF-C, interleukin-8, sVEGFR-2, sVEGFR-3, and s-kit. RESULTS: Fifty-three patients received sunitinib between July 2006 and December 2009; 51 were assessable for response. Patients received a median of two cycles (range, 1-12); 40% required dose reduction. Fatigue was the most prominent toxicity. Six patients (12%) had a confirmed radiological partial response, 34 (65%) had stable disease, and 11 (22%) had progressive disease as best response. Six of 20 patients had a decrease in fluorodeoxyglucose positron emission tomographic total glycolytic volume of 15% or more. Median overall survival was 6.1 months, and median time to progression was 3.5 months. Correlative biomarkers did not predict treatment response. CONCLUSIONS: Sunitinib has activity in a subset of patients with pretreated MPM. Consideration should be given to different treatment schedules and examination of other biomarkers for further study of sunitinib in MPM.

Lupus mastitis: a mimicker of breast carcinoma.

The authors present a case of lupus mastitis which was initially diagnosed following an incisional biopsy of a breast lump, with similar pathology found 2 years later after an ultrasound guided biopsy of the same lump. The woman had been diagnosed 7 years before with systemic lupus erythematosus. The radiological and pathological features are presented in this report with discussion of similar cases in the literature.

A novel prognostic model for malignant mesothelioma incorporating quantitative FDG-PET imaging with clinical parameters.

PURPOSE: Existing prognostic systems for malignant pleural mesothelioma do not incorporate imaging information. We aimed to identify the contribution of quantitative fluorodeoxyglucose positron emission tomography (FDG-PET) analysis to other prognostic variables in this disease. EXPERIMENTAL DESIGN: Patients with malignant pleural mesothelioma underwent helical thoracoabdominal computed tomography and FDG-PET scans at baseline. Patients were treated as clinically indicated and followed for survival. FDG-PET variables derived included total glycolytic volume, a composite of tumor volume and glycolytic activity. RESULTS: Ninety-three patients were accrued from 2003 to 2006. Of 89 eligible assessable patients, 28 had undergone pleurodesis before enrolment. Seventeen patients remained alive at analysis; median survival is 15.4 months. On univariate analysis, significant prognostic factors were: total glycolytic volume on FDG-PET (P = 0.003), sarcomatoid histology (P < 0.0005), weight loss (P = 0.031), computed tomography stage (P = 0.015), and European Organization for Research and Treatment of Cancer good prognostic score (P = 0.049). In patients with epithelioid or biphasic histology, baseline total glycolytic volume remained predictive of survival in patients with (P = 0.01) or without (P = 0.018) previous pleurodesis. In multivariate analysis, no variable other than histology contributed to the model in patients with sarcomatoid histology; total glycolytic volume and weight loss contributed to the models in patients with nonsarcomatoid histology. computed tomography-assessed tumor-node-metastasis stage did not contribute to the model. A nomogram, which incorporates quantitative PET parameters and pleurodesis into prognostic information, is presented. CONCLUSIONS: Sarcomatoid histology remains the strongest prognostic factor. In patients with non sarcomatoid disease, volumetric FDG-PET parameters are more predictive of survival than tumor-node-metastasis staging, suggesting that tumor volume and glycolytic activity may be more important determinants of prognosis in malignant pleural mesothelioma than anatomic extent of disease.

Bilateral thoracoscopy, mediastinoscopy and laparoscopy, in addition to CT, MRI and PET imaging, are essential to correctly stage and treat patients with mesothelioma prior to trimodality therapy.

BACKGROUND: Trimodality therapy (TMT; extrapleural pneumonectomy (EPP), chemotherapy and radiation therapy) offers the potential of optimal survival in selected patients with Brigham stage I-II epitheliod mesothelioma based on CT, MRI and PET scanning. We hypothesized that these scanning modalities were inadequate to accurately stage these patients. METHODS: Patients suitable for TMT, in addition to CT, MRI and PET scanning, prior to EPP, underwent bilateral thoracoscopy, mediastinoscopy and laparoscopy (surgical staging). Follow-up CT scans were performed, six monthly, quality of life assessments yearly. RESULTS: From 1 June 2004 to 28 February 2007, 34 patients were referred; mean age was 66 years (range: 44-69). Surgical staging was performed in 30 patients; 24 patients were confirmed as Brigham Stage I-II. However, six were upstaged, five as stage IV disease (one contralateral chest, two contralateral chest and abdomen, two abdomen) and one as mediastinal node positive; two further patients were reclassified histologically (one sarcomatoid, one biphasic). These eight patients fared poorly, 50% dying within 1 year from mesothelioma. Following surgical staging, 3 patients declined further surgery; thus, 19 patients proceeded to surgery, 3 were unresectable and 16 received EPP. Follow-up of all 34 patients is complete. CONCLUSION: Surgical staging identified 26% of patients who would have received no benefit from TMT.

Gynecologic and breast cancers in women after exposure to blue asbestos at Wittenoom.

INTRODUCTION: Animal studies have suggested an association between asbestos and ovarian cancer, and asbestos fibers have been detected in human ovaries. Sexual intercourse may introduce asbestos fibers into the vagina and to the cervix and ovaries. Occupational cohorts have reported excess mortality from reproductive cancers, but exposure-response relationships are inconsistent. We examine the incidence and exposure-response relationships of these cancers among 2,968 women and girls exposed to blue asbestos at Wittenoom, Western Australia. METHODS: 2,552 women were residents of the town and 416 worked for the asbestos company (Australian Blue Asbestos). Standardized incidence ratios compared the Wittenoom women with the Western Australian population. A nested case-control design and conditional logistic regression examined exposure-response relationships. RESULTS: Ovarian (standardized incidence ratio, 1.27), cervical (standardized incidence ratio, 1.44), and uterine cancer (standardized incidence ratio, 1.23) increased but not statistically significantly among the Wittenoom women compared with the Western Australian population. Among the Australian Blue Asbestos workers, cervical cancer was twice that of the Western Australian population (standardized incidence ratio, 2.38), but ovarian cancer was less (standardized incidence ratio, 0.65). Women who first arrived at Wittenoom aged >or=40 years had an odds ratio of 13.9 (95% confidence interval, 2.2-90.2) for cervical cancer compared with those aged <15 years at first arrival. Women who lived with or washed the clothes of an Australian Blue Asbestos worker did not have an increased risk for any of the gynecologic or breast cancers. DISCUSSION: There is no consistent evidence of an increased risk for gynecologic and breast cancers among the women from Wittenoom. Ovarian cancers and peritoneal mesotheliomas were not misclassified in this cohort.

Clear cell renal cell carcinoma with smooth muscle stroma.

A recent publication described 5 unusual clear cell renal tumors with prominent smooth muscle stroma that were characterized only by immunostaining. We report 3 additional tumors composed of clear cell renal cell carcinoma intimately admixed with abundant smooth muscle stroma. Epithelial differentiation of the malignant clear cell components and smooth muscle differentiation of the benign spindle cell stroma was confirmed by the immunostaining profiles and by electron microscopy. Fluorescence in situ hybridization analysis of chromosome 3 showed loss of the entire chromosome in 2 cases and loss of 3p in the third case. We therefore interpret these tumors as unique low-grade variants of clear cell renal cell carcinoma that have induced a prolific metaplastic stromal reaction. Extensive tissue sampling and immunostaining are recommended to distinguish cases with an extensive smooth muscle component from morphologically similar but benign lesions including angiomyolipoma, leiomyoma, or mixed epithelial and stromal tumor of the kidney.

Comparison of osteopontin, megakaryocyte potentiating factor, and mesothelin proteins as markers in the serum of patients with malignant mesothelioma.

INTRODUCTION: There is increasing interest in identifying a blood-based marker for the asbestos-related tumor, malignant mesothelioma. Three potential markers for mesothelioma are mesothelin, megakaryocyte potentiating factor (MPF) and osteopontin. The purpose of the current study was to directly compare these biomarkers in the same sample population, determining their sensitivity and specificity in establishing a diagnosis, and to determine if diagnostic accuracy for mesothelioma is improved by combining the data from all three markers. METHODS: Serum levels of mesothelin, MPF and osteopontin were determined by commercially available assays in 66 samples from patients with pleural malignant mesothelioma, 20 healthy individuals, 21 patients with asbestos-related lung or pleural disease, 30 patients presenting with benign pleural effusions and 30 patients with other malignancies. RESULTS: Serum levels of the three markers were elevated in mesothelioma patients. At a level of specificity of 95% relative to healthy controls and patients with benign asbestos related disease, the sensitivity for mesothelioma was 34% for MPF, 47% for osteopontin and 73% for mesothelin. Osteopontin and MPF were unable to differentiate patients with mesothelioma from patients with other malignancies or those presenting with transudative pleural effusions. Combining the data from the three biomarkers using a logistic regression model did not improve sensitivity for detecting mesothelioma above that of the mesothelin marker alone. CONCLUSION: Serum mesothelin remains the most specific marker for the diagnosis of mesothelioma.