British Journal of Cancer. 2008 Jun 10. [Epub ahead of print] [Link]

Ceresoli GL, Castagneto B, Zucali PA, Favaretto A, Mencoboni M, Grossi F, Cortinovis D, Conte GD, Ceribelli A, Bearz A, Salamina S, De Vincenzo F, Cappuzzo F, Marangolo M, Torri V, Santoro A.

1Department of Oncology, Istituto Clinico Humanitas IRCCS, Rozzano, Milano, Italy.

Abstract

The incidence of malignant pleural mesothelioma (MPM) in elderly patients is increasing. In this study, pooled data from two phase II trials of pemetrexed and carboplatin (PC) as first-line therapy were retrospectively analysed for comparisons between age groups. Patients received pemetrexed 500 mg m^-2 and carboplatin AUC 5 mg ml^-1 min^-1 intravenously every 21 days with standard vitamin supplementation. Elderly patients were defined as those >/=70 years old. A total of 178 patients with an ECOG performance status of </=2 were included. Median age was 65 years (range 38-79), with 48 patients >/=70 years (27%). Grade 3-4 haematological toxicity was slightly worse in >/=70 vs <70-year-old patients, with neutropenia observed in 25.0 vs 13.8% (P=0.11), anaemia in 20.8 vs 6.9% (P=0.01) and thrombocytopenia in 14.6 vs 8.5% (P=0.26). Non-haematological toxicity was mild and similar in the two groups. No significant difference was observed in terms of overall disease control (60.4 vs 66.9%, P=0.47), time to progression (7.2 vs 7.5 months, P=0.42) and survival (10.7 vs 13.9 months, P=0.12). Apart from slightly worse haematological toxicity, there was no significant difference in outcome or toxicity between age groups. The PC regimen is effective and well tolerated in selected elderly patients with MPM.

Keywords: malignant pleural mesothelioma; elderly patients; chemotherapy; carboplatin; pemetrexed

Clinical Nuclear Medicine. 33(7):510-512, July 2008. [Link]

Mahmood S, Martinez de Llano SR.

Department of Radiology, Nuclear Medicine Service, Memorial Sloan-Kettering Cancer Center, New York, NY, USA. smahmood@yahoo.com

Abstract

A 71-year-old man with newly diagnosed malignant mesothelioma was referred for an F-18 FDG PET/CT study to evaluate the extent of disease. PET showed mild FDG uptake in the right chest, corresponding to a lobulated, mass-like right pleural effusion versus thickening involving the entire right pleural space, and some mediastinal involvement, on the accompanying CT scan. In addition, marked FDG uptake was seen in the proximal left humerus, suspicious for an osseous metastasis. The corresponding CT scan findings of cortical thickening and a "Swiss cheese" appearance were most consistent with Paget disease. The intense FDG uptake in an osseous lesion on FDG-PET in our case reminds us of the variable nature of FDG uptake in Paget disease, the possibility of false-positive findings on FDG-PET in patients with cancer, and the usefulness of the fusion techniques in the evaluation of skeletal lesions, with the potential for discriminating between benign Paget disease and other pathologic bone findings.

American Journal of Respiratory and Critical Care Medicine.. 2008 Jun 26. [Epub ahead of print] [Link]

Park EK, Sandrini A, Yates DH, Thomas PS, Creaney J, Robinson BW, Johnson AR.

Research and Education Unit, Dust Diseases Board, Sydney, NSW, Australia.

Abstract

Rationale: Soluble mesothelin related protein (SMRP) is raised in epithelial type malignant mesothelioma (MM), but the utility of SMRP in screening for MM is unknown.

Objectives: We aimed to evaluate SMRP in asbestos exposed subjects.

Methods: 538 subjects were studied. Those with elevated SMRP (≥ 2.5nM) underwent further investigation including positron-emission tomography/computed tomography.

Measurements and Main Results: Mean (± SD) SMRP in healthy subjects exposed to asbestos (n=223) was 0.79 (± 0.45) nM. 15 subjects had elevated SMRP, of whom one had lung cancer which was successfully resected. Another with lung cancer was undetected by SMRP. No subjects were diagnosed with MM. Mean SMRP in healthy subjects was significantly lower than in subjects with PPs (p<0.01).

Conclusions: This is the first large scale prospective study of SMRP for screening for malignancy in asbestos-exposed individuals. A high false positive rate was observed. SMRP seems unlikely to prove useful in screening for MM.

Keywords: soluble mesothelin related protein, mesothelioma, asbestos-related disorders, diagnostic accuracy, screening

Cancer Treatment and Research. 2008;143:281-97. [Link]

Hinshaw JL, Pickhardt PJ.

Department of Radiology, University of Wisconsin Medical School, Madison, WI, 53792, USA.

Abstract

Peritoneal carcinomatosis and metastatic involvement of the retroperitoneum are relatively common manifestations of many organ-based malignancies and lymphoproliferative disorders. Primary malignancies of peritoneal and retroperitoneal origin occur much less frequently, and can be difficult to distinguish from metastatic disease. In many cases, a precise diagnosis based on imaging findings alone is not possible. However, the imaging features of these primary tumors, in combination with the clinical and demographic data, can be utilized to narrow the scope of the differential diagnosis. This chapter will present the clinical and imaging features of primary peritoneal and retroperitoneal tumors arising from the various tissue components that comprise the ligaments, mesenteries and connective tissues of these anatomic spaces.

Journal of Occupational Medicine and Toxicology. 2008 Sep 8;3:20. [Link]

Miles SE, Sandrini A, Johnson AR, Yates DH.

Dust Diseases Board Research & Education Unit, Sydney, NSW, Australia. Deborahy88@hotmail.com.

Abstract

Asbestos-related diffuse pleural thickening (DPT), or extensive fibrosis of the visceral pleura secondary to asbestos exposure, is increasingly common due to the large number of workers previously exposed to asbestos. It may coexist with asbestos related pleural plaques but has a distinctly different pathology. The pathogenesis of this condition as distinct from pleural plaques is gradually becoming understood. Generation of reactive oxygen and nitrogen species, profibrotic cytokines and growth factors in response to asbestos is likely to play a role in the formation of a fibrinous intrapleural matrix. Benign asbestos related pleural effusions commonly antedate the development of diffuse pleural thickening. Environmental as well as occupational exposure to asbestos may also result in pleural fibrosis, particularly in geographic areas with naturally occurring asbestiform soil minerals. Pleural disorders may also occur after household exposure. High resolution computed tomography (CT) is more sensitive and specific than chest radiography for the diagnosis of diffuse pleural thickening, and several classification systems for asbestos-related disorders have been devised. Magnetic resonance imaging and fluorodeoxyglucose positron emission tomography (PET) scanning may be useful in distinguishing between DPT and malignant mesothelioma. DPT may be associated with symptoms such as dyspnoea and chest pain. It causes a restrictive defect on lung function and may rarely result in respiratory failure and death. Treatment is primarily supportive.

Investigative Radiology. 2008 Oct;43(10):737-44. [Link]

Plathow C, Staab A, Schmaehl A, Aschoff P, Zuna I, Pfannenberg C, Peter SH, Eschmann S, Klopp M.

Department of Diagnostic Radiology, University of Tuebingen, Tuebingen, Germany. christian.plathow@uniklinik-freiburg.de

Abstract

Objective: To evaluate and compare the role of computed tomography (CT), positron emission tomography (PET), PET/CT, and magnetic resonance imaging (MRI) in the correct staging of patients with limited malignant pleural mesothelioma (MPM).

Materials and Methods: Fifty-four patients with an epithelial MPM (34 men and 20 women) were included in this study. Patients were referred to our department for staging in a predicted resectable state (stage II/III). Within 3 days, PET/CT and MRI was performed in all patients. Images were evaluated by 3 specialists in the field of PET/CT and MRI. The subexaminations of PET/CT, PET, and CT were independently evaluated with respect to tumor stage. Subexaminations were compared with each other, with MRI and PET/CT. N-stage was verified by mediastinoscopy. Afterward, consensus reading was performed.

In 52 patients, surgery served as gold standard. In 2 patients, follow-up control served as gold standard as an inoperable situation with distant metastases was found. Additionally, interobserver variability ([kappa] value) was calculated.

Results: In stage II, accuracy was 0.77 (CT), 0.86 (PET), 0.8 (MRI), 1.0 (PET/CT), and in stage III 0.75, 0.83, 0.9, 1.0. PET/CT was significantly more accurate (P < 0.05) in stages II and III compared with all other techniques. CT and MRI were not able to detect distant metastases in 2 patients, which changed therapy (operable vs. inoperable). Interobserver variability was 0.7, 0.9, 0.8, 1.0 in stage II and 0.9, 0.9, 0.9, 1.0 in stage III.

Conclusion: PET/CT makes it possible to stage patients with limited MPM with high accuracy and low interobserver variability.

European Journal of Cardio-Thoracic Surgery. 2008 Nov;34(5):1090-6. Epub 2008 Sep 16. [Link]

Sørensen JB, Ravn J, Loft A, Brenøe J, Berthelsen AK; Nordic Mesothelioma Group.

Aaseboe U, Billing B, Bjørck T, Brodin O, Brunsvig P, Forsløw U, Frank H, Hansen O, Harving H, Hillerdal G, Jakobsen KD, Johansson A, Ladegaard L, Lindh B, Melgaard P, Mygind N, Månsson T, Palshof T, Sundstrøm S, Sørensen P, Vigander T.

Department of Oncology, Finsen Centre/National University Hospital, Copenhagen, Denmark. jens.benn.soerensen@rh.regionh.dk

Abstract

Objectives: Extrapleural pneumonectomy (EPP) in MPM may be confined with both morbidity and mortality and careful preoperative staging identifying resectable patients is important. Staging is difficult and the accuracy of preoperative CT scan, 18F-FDG PET/CT scan (PET/CT), and mediastinoscopy is unclear. The objectives were to compare these staging techniques to each other and to surgical–pathological findings.

Methods: Patients had epithelial subtype MPM, age ≤70 years, and lung function test allowing pneumonectomy. Preoperative staging after 3–6 courses of induction chemotherapy included conventional CT scan, PET/CT, and mediastinoscopy. Surgical–pathological findings were compared to preoperative findings.

Results: Forty-two consecutive patients were without T4 or M on CT scan. PET/CT showed inoperability in 12 patients (29%) due to T4 (7 patients) and M1 (7 patients). Among 30 patients with subsequent mediastinoscopy, including 10 with N2/N3 on PET/CT, N2 were histologically verified
in 6 (20%). Among 24 resected patients, T4 occurred in 2 patients (8%), and N2 in 4 (17%), all being PET/CT negative. PET/CT accuracy of T4 and N2/N3 compared to combined histological results of mediastinoscopy and EPP showed sensitivity, specificity, positive predictive value, negative predictive value, and positive and negative likelihood ratios of 78% and 50%, 100% and 75%, 100% and 50%, 94% and 75%, not applicable and 5.0, and 0.22 and 0.67, respectively.

Conclusions: Non-curative surgery is avoided in 29% out of 42 MPM patients by preoperative PET/CT and in further 14% by mediastinoscopy. Even though both procedures are valuable, there are false negative findings with both, urging for even more accurate staging procedures.

Keywords: Mesothelioma; Staging; PET/CT scan; Mediastinoscopy; Extrapleural pneumonectomy

Nuclear Medicine and Biology. 2008 Nov;35(8):851-60. [Link]

Saito Y, Furukawa T, Arano Y, Fujibayashi Y, Saga T.

Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, 263-8555, Japan.

Abstract

Introduction: Various techniques are available for in vivo imaging, and precise understanding of their characteristics is essential for effective use of the imaging results. We established human mesothelioma cell lines expressing red fluorescent protein (RFP) and examined their fluorescence intensity and uptake of positron emission tomography (PET) tracer analogs to compare their characteristics and assess their usefulness in the evaluation of therapeutics.

Method: A human mesothelioma cell line was stably transfected to express RFP. Fluorescence, cell number and protein amount were measured during cell growth and treatment with cytotoxic reagents. In in vivo experiments, RFP-expressing cells were injected subcutaneously or into the pleural cavity of nude mice, and fluorescence images were taken with or without pemetrexed treatment. The uptake of [³H]3′-deoxy-3′-fluorothymidine ([³H]FLT) and [¹⁴C]2-fluoro-2-deoxy-d-glucose ([¹⁴C]FDG) under treatment with the above reagents in vitro and in vivo were examined.

Results: Strong correlation was observed between fluorescence intensity and total cell number with or without cytotoxic treatment. The uptake of [³H]FLT and [¹⁴C]FDG decreased rapidly after the initiation of treatment with actinomycin D or cycloheximide. When treated with pemetrexed, the uptake of [³H]FLT temporarily increased. The cells formed subcutaneous and orthotopic tumors, with fluorescence intensity correlating with tumor volume. The correlation was sustained under pemetrexed treatment. The uptake of [³H]FLT in vivo increased significantly early after pemetrexed treatment.

Conclusion: Fluorescence imaging could be used to semiquantitatively monitor tumor size, whereas PET could be used to monitor tumor response to therapeutic treatments, and especially, FLT might be a good marker of the response to anti-folate chemotherapeutics.

Keywords: Mesothelioma; Mouse tumor model; Fluorescence imaging; PET; FLT

Internal Medicine. 2008;47(23):2053-6. Epub 2008 Dec 1. [Link]

Kimura T, Koyama K, Kudoh S, Kawabe J, Yoshimura N, Mitsuoka S, Shiomi S, Hirata K.

Department of Respiratory Medicine, Osaka City University, Osaka. kimutats@med.osaka-cu.ac.jp

Abstract

We report a 56-year-old man who underwent monitoring of the response to chemotherapy of malignant pleural mesothelioma (MPM). ⁸F-fluoro-2-deoxy-_D-glucose positron emission tomography (FDG-PET) and computed tomography (CT) were performed prior to chemotherapy and after the first and second courses of chemotherapy. The tumor lesion exhibited shrinkage on CT and a decrease in the standardized uptake value (SUV) max after the first course of chemotherapy, but exhibited size enlargement and an increase in SUV max after the second course of chemotherapy. These findings suggest that results of quantification of metabolic response by FDG-PET are related to the objective response as determined by CT in patients with MPM.

Keywords: FDG-PET, mesothelioma, SUV, response

European Journal of Nuclear Medicine and Molecular Imaging. 2011 Jan 6. [Epub ahead of print] [Link]

Gerbaudo VH, Mamede M, Trotman-Dickenson B, Hatabu H, Sugarbaker DJ.

Division of Nuclear Medicine and Molecular Imaging, Brigham & Women’s Hospital, Harvard Medical School, 75 Francis St., Boston, MA, 02115, USA, vgerbaudo@partners.org.

Abstract

Purpose: This study investigated the diagnostic performance and prognostic value of fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT in suspected malignant pleural mesothelioma (MPM) recurrence, in the context of patterns and intensity of FDG uptake, histologic type, and treatment algorithm.

Methods: Fifty patients with MPM underwent FDG PET/CT for restaging 11 ± 6 months after therapy. Tumor relapse was confirmed by histopathology, and by clinical evolution and subsequent imaging. Progression-free survival was defined as the time between treatment and the earliest clinical evidence of recurrence. Survival after FDG PET/CT was defined as the time between the scan and death or last follow-up. Overall survival was defined as the time between initial treatment and death or last follow-up date.

Results: Treatment failure was confirmed in 42 patients (30 epithelial and 12 non-epithelial MPM). Sensitivity, specificity, accuracy, negative predictive value, and positive predictive value for FDG PET/CT were 97.6, 75, 94, 86, and 95.3%, respectively. FDG PET/CT evidence of single site of recurrence was observed in the ipsilateral hemithorax in 18 patients (44%), contralaterally in 2 (5%), and in the abdomen in 1 patient (2%). Bilateral thoracic relapse was detected in three patients (7%). Simultaneous recurrence in the ipsilateral hemithorax and abdomen was observed in ten (24%) patients and in seven (17%) in all three cavities. Unsuspected distant metastases were detected in 11 patients (26%). Four patterns of uptake were observed in recurrent disease: focal, linear, mixed (focal/linear), and encasing, with a significant difference between the intensity of uptake in malignant lesions compared to benign post-therapeutic changes. Lesion uptake was lower in patients previously treated with more aggressive therapy and higher in intrathoracic lesions of patients with distant metastases. FDG PET/CT helped in the selection of 12 patients (29%) who benefited from additional previously unplanned treatment at the time of failure. Multivariate analysis showed that histologic type remained the only independent predictor of progression-free survival. Survival after relapse was independently predicted by the pattern of FDG uptake and PET nodal status, and overall survival by the maximum standard uptake value.

Conclusion: FDG PET/CT is an accurate modality to diagnose and to estimate the extent of locoregional and distant MPM recurrence, and it carries independent prognostic value. Once the disease recurs, survival outcomes seem to be independent of histologic type and highly dependent on the intensity of lesion uptake and on the pattern of metabolically active disease in FDG PET/CT. Our observations should be considered limited to patients treated surgically with or without perioperative therapies and should not be extrapolated to those unresectable cases treated with chemotherapy alone.

Keywords FDG, FDG PET/CT, Mesothelioma, Lung cancer, Response to treatment, Recurrence, Survival

Lung Cancer.. 2012 Nov 30. pii: S0169-5002(12)00619-8. doi: 10.1016/j.lungcan.2012.10.017. [Epub ahead of print] [Link]

Roca E, Laroumagne S, Vandemoortele T, Berdah S, Dutau H, Maldonado F, Astoul P.

Department of Thoracic Oncology, Pleural Diseases, and Interventional Pulmonology, Hôpital Nord, Marseille, France.

Abstract

Malignant mesothelioma (MM) is an uncommon neoplasm with a poor prognosis usually associated with asbestos exposure. 18F-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) has become an invaluable tool for the diagnosis, staging, and prognosis of this severe disease as it combines both anatomic and functional information in a single imaging procedure, allowing for improved management of this disease. For many authors, 18F-FDG-PET/CT is the cornerstone of the pre-therapeutic evaluation of mesothelioma patients, particularly when multimodal therapy (including extra-pleural pneumonectomy or omentectomy) is considered. However, while characteristic patterns have been reported as predictive of macroscopic pleural or peritoneal involvement, false negative findings are possible, both for pleural and peritoneal mesothelioma, during the initial diagnosis or during the patient’s surveillance as illustrated by this report of three cases of suspected MM with negative PET/CT. This report highlights the limitations of PET/CT in the diagnostic evaluation of MM and the importance of histopathological confirmation by thoracoscopy and/or laparoscopy, which remain the most important diagnostic procedures in MM.

Hellenic Journal of Nuclear Medicine. 2012 Sep-Dec;15(3):252-3. [Link]

Basu S, Rekhi B, Shamim SA, Jambhekar NA.

Radiation Medicine Centre (B.A.R.C), Tata Memorial Centre Annexe, Jerbai Wadia Road, Parel, Mumbai 400012, India. drsanb@yahoo.com.

Abstract

An aggressive second primary in the form of a lung adenocarcinoma with a rapidly progressive fatal course is described in the setting of a metastasizing differentiated papillary carcinoma of the thyroid. The patient, first presented in HJNM, was a 58 year old male, diagnosed with papillary thyroid carcinoma and renal metastases one year back, for which he had undergone a total thyroidectomy with neck nodal dissection.

The final histopathologic diagnosis was a differentiated papillary carcinoma of thyroid with lymph node metastases. The patient was also diagnosed with multifocal renal metastases that demonstrated varying degree of radioiodine ((131)I) uptake and a flip-flop pattern with (18)F-FDG-PET study. His thyroglobulin (Tg) was more than 250ng/mL and was treated with two doses of (131)I in two visits of 6 months’ apart. Post-treatment (131)I scan on both occasions had shown uptake in the renal metastases of both sides and in the residual thyroid tissue. No lung lesion was shown in PET and X-rays studies at that time.

Recently, he developed progressive dyspnoea and underwent (18)F-FDG-PET/CT at a different centre. The present PET/CT study showed nodular thickening involving the visceral and parietal surfaces of the entire right pleura (SUV(max) 16.5) with bilateral small nodules in the lung. The lesions were initially diagnosed as non-iodine avid metastases. However, in view of his rapidly progressive symptoms that were discordant with the tumor characteristics of the primary, he underwent computed tomogram (CT) guided right-sided pleural based mass biopsy for pathological diagnosis.

On histopathology, the impression was that of a poorly differentiated carcinoma with glandular traits with focal papillary architecture. In view of possibility of a second primary, for objective diagnosis immunohistochemical (IHC) markers were examined and their staining showed diffuse positivity for surfactant protein, TTF-1 and CK7, along with cytokeratin (CK), epithelial membrane antigen (EMA), cytokeratin-19 (CK19) CD10 positivity and anti-mesothelioma antibody (HBME1) negativity. Overall morphological features and IHC profile were consistent with a high grade lung adenocarcinoma.

Mesothelioma was further ruled out, based on HBME-1 and calretinin negativity. A second malignancy in a patient of thyroid carcinoma with non-iodine avid metastatic disease is more commonly encountered and suspected in practice in the context of a low serum Tg. The whole body (18)F-FDG-PET/CT can at times aid this diagnosis. However, as in our case, this can occur even in the setting of very high Tg. Quite frequently, in routine practice, these non-iodine avid (18)F-FDG-PET positive lesions are interpreted as non-iodine concentrating metastases due to de-differentiation with no further treatment administered. Histological assessment and application of a panel of IHC markers like positive expression of surfactant B protein, apart from CK7 immunostaining diagnosed the second primary in the present case.

The patient unfortunately died during the first cycle of palliative chemotherapy. In conclusion, in this communication an aggressive second malignancy in the lungs was diagnosed 13 months after the initial diagnosis in a patient with papillary metastatic thyroid carcinoma that appeared to be non-iodine avid metastasis in the setting of significantly raised serum thyroglobulin. The case underscores the value of histopathological and immunohistochemical correlation in appropriate cases.

Abdominal Imaging. 2014 August 20. [Epub ahead of print] [Link]

Vicens RA, Patnana M, Le O, Bhosale PR, Sagebiel TL, Menias CO, Balachandran A.

Abstract

Peritoneal disease can be caused by a wide spectrum of pathologies. While peritoneal disease is usually caused by primary or secondary malignancies, benign diseases can occur and mimic malignancies. This article begins with an overview of peritoneal embryology and anatomy followed by a detailed description of the multimodality imaging appearance of peritoneal diseases. Common diseases include peritoneal carcinomatosis, pseudomyxoma peritonei, lymphomatosis, sarcomatosis, and tuberculous peritonitis. The uncommon diseases which cause peritoneal disease include desmoid fibromatosis, desmoplastic small round cell tumor, malignant mesothelioma, well-differentiated mesothelioma, multicystic mesothelioma, papillary serous carcinoma, leiomyomatosis, extramedullary hematopoiesis, inflammatory pseudotumor and amyloidosis. This manuscript will help the radiologist become familiar with the different peritoneal spaces, pathways of spread, multimodality imaging appearance and differential diagnoses of peritoneal diseases in order to report the essential information for surgeons and oncologists to plan treatment.

Journal of Computer Assisted Tomography 2014 Oct 28 [Epub ahead of print] [Link]

Frauenfelder T, Kestenholz P, Hunziker R, Nguyen TD, Fries M, Veir Haibach P, Husmann L, Stahel R, Weder W, Opitz I.

Abstract

Purpose

The objective of this study was to determine the diagnostic value of computed tomography (CT) and positron emission tomography (PET)/CT for staging of malignant pleural mesothelioma (MPM) in patients undergoing induction chemotherapy.

Methods

Sixty-two patients (median age, 61 years; female: n = 9) with proven MPM underwent CT after induction chemotherapy. Of these, 28 underwent additional PET/CT. Extrapleural pneumonectomy was performed for pathological TNM staging. Clinical TNM stage was assessed by 3 independent readers. Relative and absolute underestimation and overestimation were compared with pathological tumor stage. Sensitivity, specificity, and accuracy for differentiation between stages T2 and T3 were assessed. Interobserver agreement between the readers was analyzed (κ).

Results

Positron emission tomography/CT and CT underestimated T stage in up to 30% of the cases. Positron emission tomography/CT had a higher accuracy for tumor extent compared with CT (PET/CT: 0.92; CT: 0.84). The accuracy for nodal staging was higher for CT than for PET/CT (PET/CT: 0.78; CT: 0.87). Concerning International Mesothelioma Interest Group classification, PET/CT improved the accuracy of preoperative staging compared with CT (PET/CT: 0.91; CT: 0.82). Interobserver agreement was moderate for CT (0.48-0.62) and good for PET/CT (0.64-0.83) for T staging. For nodal staging, interobserver agreement was fair to moderate for CT and good for PET/CT (CT: 0.37-0.51; PET/CT: 0.73-0.76).

Conclusions

Positron emission tomography/CT is more accurate and has a lower interobserver variability for clinical intrathoracic staging of MPM compared with CT. Nevertheless PET/CT underestimated tumor stage in a substantial number of cases, showing the need for a more accurate imaging technology or approach.

Respiration 2015 May 8 [Epub ahead of print] [Link]

Pinelli V, Roca E, Lucchini S, Laroumagne S, Loundou A, Dutau H, Maldonado F, Astoul P.

Abstract

Background

Careful clinical staging in patients with malignant pleural mesothelioma (MPM) is fundamental in management planning. Positron emission tomography/computed tomography (PET/CT) is increasingly recognized as an important staging modality.

Objectives

The purpose of this study was to assess whether the metabolic activity of the pleural tumor detected with PET/CT correlates with specific endoscopic features and pleural distribution of the lesions as assessed by medical thoracoscopy.

Methods

Consecutive patients with MPM and available PET/CT performed before thoracoscopy were separated into 2 groups, according to their standardized uptake value (SUV). Kaplan-Meier-analysis for survival was performed on groups with low and high SUV. Agreement between PET/CT and thoracoscopy evaluation was analyzed using Cohen’s kappa coefficient. The Wilcoxon test was used to compare the median SUV, and the χ2 test was used to evaluate differences in endoscopic findings.

Results

A total of 32 patients were included. The median maximum SUV (SUV max) was 6.1 and patients were separated into 2 groups based on this cutoff. Patients with SUV max Conclusions

PET/CT data may be predictive of thoracoscopic features of MPM associated with prognosis and staging, but the correlation is moderate at best. A degree of disagreement exists between these two modalities, which supports thoracoscopy as the gold standard for assessment of local invasion in MPM.

Lung Cancer 2015 July 29 [Epub ahead of print] [Link]

Armato SG 3rd, Coolen J, Nowak AK, Robinson C, Gill RR, Straus C, Khanwalkar A.

Abstract

Imaging of malignant pleural mesothelioma is essential to patient management, prognostication, and response assessment. From animal models to clinical trials, the gamut of research activities and clinical standards relies on imaging to provide information on lesion morphology and the growing number of physiologic characteristics amenable to capture through imaging techniques. The complex morphology, growth pattern, and biological mechanisms of mesothelioma, however, present challenges for image acquisition and interpretation. Nevertheless, novel approaches to image acquisition and subsequent image analysis have expanded the opportunities for (as well as the need for) imaging in this disease. This paper summarizes the imaging-based research presented orally at the 2014 International Conference of the International Mesothelioma Interest Group (iMig) in Cape Town, South Africa, October 2014. Presented topics include the imaging of hypoxia in a murine model through positron emission tomography (PET), the use of diffusion-weighted magnetic resonance imaging (MRI) to assess the histologic composition of biphasic mesothelioma and to assess early response to chemotherapy, the correlation of CT-based tumor volume with the volume of the post-surgical tumor specimen, the development of volumetric tumor response criteria, and pre-treatment tumor volume growth considerations for tumor response assessment.

Clinical Case Reports 2015 October [Link]

Fujita K, Kim YH, Nakatani K, Mio T.

Abstract

Refractory empyema occasionally reflects hidden malignant disease. We presented a rare case of rapidly progressive malignant mesothelioma of the pleura (MPM) mimicking empyema. Physicians should be aware of MPM when patients with empyema are refractory to the standard treatment, and PET-CT may be helpful in establishing a precise diagnosis in such cases.

Respiratory Medicine Case Reports 2016 July 12 [Link]

DeLapp D1, Chan C1, Nystrom P

Abstract

Mesothelioma is a rare pulmonary malignancy commonly associated with asbestos exposure. Its presentation is insidious and non-specific, with complaints of chest pain, dyspnea and cough. Chest X-ray may demonstrate unilateral pleural effusion. CT and PET scans may highlight nodular pleural plaques. Diagnosis often times is difficult with negative imaging and negative pleural fluid studies. In rare cases, hydropneumothoraces may be seen. We report a case of malignant pleural mesothelioma presenting as recurrent hydropneumothorax with negative CT scan of the chest for pleural abnormalities and negative pleural fluid studies.

BMJ Case Reports 2016 October 4 [Link]

Ertan G, Eren A, Ulus S

Abstract

Mesothelioma is an uncommon malignant neoplasm and a localised form of the pleura is especially very rare. Diagnosis of localised malignant pleural mesothelioma (LMPM) is very challenging. Histopathological verification is the gold standard, and studies such as CT, positron emission tomography (PET) and thoracoscopy are very valuable tools in assisting diagnosis. We report a case of histopathologically proven LMPM, which was discovered as a well circumscribed solitary subpleural nodule on PET-CT after presentation with cranial metastasis. This case shows that LMPM can present with uncommon radiological and clinical appearances, and imaging tools such as PET-CT have a very important role in diagnosis.

Acta Oncologica 2016 October 12 [Epub ahead of print] [Link]

Botticella A, Defraene G, Nackaerts K, Deroose CM, Coolen J, Nafteux P, Peeters S, Ricardi U, De Ruysscher D

Abstract

BACKGROUND:
The gross tumor volume (GTV) definition for malignant pleural mesothelioma (MPM) is ill-defined. We therefore investigated which imaging modality is optimal: computed tomography (CT) with intravenous contrast (IVC), positron emission tomography-CT (PET/CT) or magnetic resonance imaging (MRI).
MATERIAL AND METHODS:
Sixteen consecutive patients with untreated stage I-IV MPM were included. Patients with prior pleurodesis were excluded. CT with IVC, 18FDG-PET/CT and MRI (T2 and contrast-enhanced T1) were obtained. CT was rigidly co-registered with PET/CT and with MRI. Three sets of pleural GTVs were defined: GTVCT, GTVCT+PET/CT and GTVCT+MRI. Quantitative and qualitative evaluations of the contoured GTVs were performed.
RESULTS:
Compared to CT-based GTV definition, PET/CT identified additional tumor sites (defined as either separate nodules or greater extent of a known tumor) in 12/16 patients. Compared to either CT or PET/CT, MRI identified additional tumor sites in 15/16 patients (p = .7). The mean GTVCT, GTVCT+PET/CT and GTVCT+MRI [±standard deviation (SD)] were 630.1 cm3 (±302.81), 640.23 cm3 (±302.83) and 660.8 cm3 (±290.8), respectively. Differences in mean volumes were not significant. The mean Jaccard Index was significantly lower in MRI-based contours versus all the others.
CONCLUSION:
As MRI identified additional pleural disease sites in the majority of patients, it may play a role in optimal target volume definition.