Survival of pleurectomy-decortication and hyperthermic chemotherapy in mesothelioma

Background

This study aims to evaluate overall survival, diseasefree survival, and prognostic factors in patients undergoing pleurectomy-decortication and hyperthermic intrathoracic chemotherapy with the diagnosis of malignant pleural mesothelioma.

Methods

Between January 2020 and November 2021, a total of 53 patients (27 males, 26 females; mean age: 58.1±1.3 years; range, 39 to 81 years) who underwent pleurectomy-decortication and hyperthermic intrathoracic chemotherapy with the diagnosis of malignant pleural mesothelioma were retrospectively analyzed. Data including characteristics, comorbidities, postoperative complications, recurrence and mortality status of the patients were recorded. Overall survival and disease-free survival and prognostic factors were evaluated.

Results

The median disease-free survival was 11.67 months and the median overall survival was 24.60 months. The median disease-free survival was 8.80 months in men and 13.17 months in women, indicating a statistically significant difference as it showed that recurrence was detected earlier in male patients (p=0.037). The median disease-free survival and overall survival was 6.13 months and 11.70 in cases diagnosed with biphasic mesothelioma, respectively, while it was 11.67 months and 25.46 months in cases with epithelial mesothelioma, respectively. Pathological subtype was found to be an effective prognostic factor for both survival (p=0.049 and p<0.001, respectively).

Conclusion

Hyperthermic intrathoracic chemotherapy following cytoreductive surgery is a preferable and tolerable method in the treatment of malignant pleural mesothelioma. While evaluating surgical indications, it should be kept in mind that cases with epithelial mesothelioma may benefit more from surgical treatment.

Training and validation of a knowledge-based dose-volume histogram predictive model in the optimisation of intensity-modulated proton and volumetric modulated arc photon plans for pleural mesothelioma patients

BACKGROUND

To investigate the performance of a narrow-scope knowledge-based RapidPlan (RP) model for optimisation of intensity-modulated proton therapy (IMPT) and volumetric modulated arc therapy (VMAT) plans applied to patients with pleural mesothelioma. Second, estimate the potential benefit of IMPT versus VMAT for this class of patients.

METHODS

A cohort of 82 patients was retrospectively selected; 60 were used to "train" a dose-volume histogram predictive model; the remaining 22 provided independent validation. The performance of the RP models was benchmarked, comparing predicted versus achieved mean and near-to-maximum dose for all organs at risk (OARs) in the training set and by quantitative assessment of some dose-volume metrics in the comparison of the validation RP-based data versus the manually optimised training datasets. Treatment plans were designed for a prescription dose of 44 Gy in 22 fractions (proton doses account for a fixed relative biological effectiveness RBE = 1.1).

RESULTS

Training and validation RP-based plans resulted dosimetrically similar for both VMAT and IMPT groups, and the clinical planning aims were met for all structures. The IMPT plans outperformed the VMAT ones for all OARs for the contra-lateral and the mean and low dose regions for the ipsilateral OARs. Concerning the prediction performance of the RP models, the linear regression for the near-to-maximum dose resulted in D_achieved = 1.03D_predicted + 0.58 and D_achieved = 1.02D_predicted + 1.46 for VMAT and IMPT, respectively. For the mean dose it resulted: D_achieved = 0.99D_predicted + 0.34 and D_achieved = 1.05D_predicted + 0.27 respectively. In both cases, the linear correlation between prediction and achievement is granted with an angular coefficient deviating from unity for less than 5%. Concerning the dosimetric comparison between manual plans in the training cohort and RP-based plans in the validation cohort, no clinical differences were observed for the target volumes in both the VMAT and IMPT groups. Similar consistency was observed for the dose-volume metrics analysed for the OAR. This proves the possibility of achieving the same quality of plans with manual procedures (the training set) or with automated RP-based methods (the validation set).

CONCLUSION

Two models were trained and validated for VMAT and IMPT plans for pleural mesothelioma. The RP model performance resulted satisfactory as measured by the agreement between predicted and achieved (after full optimisation) dose-volume metrics. The IMPT plans outperformed the VMAT plans for all the OARs (with different intensities for contra- or ipsilateral structures). RP-based planning enabled the automation of part of the optimisation and the harmonisation of the dose-volume results between training and validation. The IMPT data showed a systematic significant dosimetric advantage over VMAT. In general, using an RP-based approach can simplify the optimisation workflow in these complex treatment indications without impacting the quality of plans.

Relationship Between Physical Function and Health Utility in Patients Undergoing Surgical Treatment for Malignant Pleural Mesothelioma

PURPOSE

Health utility, which is a measure of patient-reported outcome (PRO), has recently been used in health-related quality of life for patients with various cancers. However, the relationship between health utility and the physical function and of patients undergoing pleurectomy/decortication (P/D) as surgical treatment for malignant pleural mesothelioma (MPM) has not been reported in the perioperative and convalescent phases. This study aimed to evaluate the perioperative and postoperative health utility of patients undergoing P/D for MPM at one year postoperatively and to examine the relationship with physical function.

METHODS

We included patients underwent P/D. Grip strength, knee extension strength, 6-minute walk distance (6MWD), forced vital capacity (FVC), and forced expiratory volume in one second (FEV1) were measured to assess physical function, and the Short-Form Six-Dimension (SF-6D) was completed to assess health utility. These assessments were performed preoperatively, postoperatively, and one year postoperatively. Statistical analysis was performed using one-way analysis of variance for comparison of pre and postoperative and one year mean values.

RESULTS

There were 24 subjects (23 males, 65.5±8.3 year). SF-6D, 6MWD, FVC, and FEV1 values one year operatively improved significantly compared with postoperative. Additionally, SF-6D was correlated with 6MWD.

CONCLUSION

Health utility were also correlated with exercise capacity.

The prognostic value of 18F-fluorodeoxyglucose positron emission tomography/ computed tomography parameters in patients with malignant pleural mesothelioma

Background

In this study, we aimed to investigate the prognostic value of metabolic ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography parameters in malignant pleural mesothelioma patients.

Methods

A total of 65 patients with malignant pleural mesothelioma (34 males, 31 females; median age: 60 years; range, 39 to 84 years) who underwent whole-body ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography for staging before treatment between March 2008 and January 2018 were included. Relationships between clinicopathological factors and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography parameters and overall survival were evaluated using a log-rank test and Cox regression analysis.

Results

The median follow-up was 13 (range, 4 to 55) months. The Kaplan-Meier analysis revealed a mean survival time of 17±2.6 months. The cumulative two- and five-year survival rates were 34.8% and 7.8%, respectively. Univariate analysis showed that ≥60 age, left hemithorax involvement, a maximum standardized uptake value of ≥9.8, c-T4 status, c-M1 status, and non-surgery were negatively associated with overall survival (p<0.05). Multivariate analysis showed that ≥60 age, left hemithorax involvement, a maximum standardized uptake value of ≥9.8, c-M1 status, and a total lesion glycolysis of ≥180.2 g were negatively associated with overall survival (p<0.05).

Conclusion

Metabolic parameters of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography have the potential to provide prognostic information for malignant pleural mesothelioma patients who are receiving surgery and/or chemotherapy.

Updates in Staging and Management of Malignant Pleural Mesothelioma

While without treatment, malignant pleural mesothelioma (MPM) confers poor survival, cancer-directed surgery as part of multimodality treatment is associated with a 15% 5-year survival. Extrapleural pneumonectomy (EPP) and radical or extended pleurectomy/decortication (P/D) are the 2 types of resection performed in this context. Preoperative staging is critical to patient selection for surgery; P/D is recommended over EPP in most cases. Adjuvant therapy with intraoperative platforms, traditional chemotherapy, hemithoracic radiotherapy resection, and new immunotherapy agents are instrumental in achieving durable long-term results. We outline the latest understanding of disease staging and describe the current state of literature and practice.

Addition of radiotherapy to surgery and chemotherapy improves survival in localized malignant pleural mesothelioma: A Surveillance, Epidemiology, and End Results (SEER) study

INTRODUCTION

Malignant pleural mesothelioma (MPM) is a devastating disease with poor survival outcomes for most patients. Optimizing therapeutic approaches is thus vital, but has been hampered by a dearth of randomized trials to guide decision making. We used a population-level database to evaluate the impact of radiotherapy as a component of trimodality therapy on overall survival (OS) in MPM.

METHODS

We retrospectively reviewed the SEER Radiation/Chemotherapy database for patients with MPM who received surgery and chemotherapy, with or without radiotherapy. A propensity score-matched analysis with inverse probability of treatment weighting (IPTW) was performed. Weight-adjusted univariate KM analysis was performed and doubly robust, IPTW-adjusted multivariable cox proportional hazards regression modeling was also performed to quantify the effect of radiotherapy on OS in trimodality therapy for MPM.

RESULTS

1015 patients were identified. 678 patients received surgery and chemotherapy, and 337 patients received trimodality therapy. For patients with localized disease, OS was significantly improved with trimodality therapy (HR 0.56, CI 0.4 - 0.8, p = 0.001), which persisted with IPTW adjustment (HR 0.65, CI 0.49 - 0.95, p = 0.0248). No significant benefit was seen for patients with regional or distant disease. On multivariate analysis, positive predictors of survival after IPTW adjustment were female sex, diagnosis after 2005, and left-sided disease.

CONCLUSIONS

These findings support a significant benefit to OS by incorporating radiotherapy as a component of trimodality therapy for patients with localized MPM compared to only surgery and chemotherapy. It does not provide a significant overall survival benefit for patients with regional or metastatic disease.

Light Fluence Rate and Tissue Oxygenation (St O2 ) Distributions Within the Thoracic Cavity of Patients Receiving Intraoperative Photodynamic Therapy for Malignant Pleural Mesothelioma

The distributions of light and tissue oxygenation (S_t O₂ ) within the chest cavity were determined for 15 subjects undergoing macroscopic complete resection followed by intraoperative photodynamic therapy (PDT) as part of a clinical trial for the treatment of malignant pleural mesothelioma (MPM). Over the course of light delivery, detectors at each of eight different sites recorded exposure to variable fluence rate. Nevertheless, the treatment-averaged fluence rate was similar among sites, ranging from a median of 40-61 mW cm^-2 during periods of light exposure to a detector. S_t O₂ at each tissue site varied by subject, but posterior mediastinum and posterior sulcus were the most consistently well oxygenated (median S_t O₂ >90%; interquartile ranges ~85-95%). PDT effect on S_t O₂ was characterized as the S_t O₂ ratio (post-PDT S_t O₂ /pre-PDT S_t O₂ ). High S_t O₂ pre-PDT was significantly associated with oxygen depletion (S_t O₂ ratio < 1), although the extent of oxygen depletion was mild (median S_t O₂ ratio of 0.8). Overall, PDT of the thoracic cavity resulted in moderate treatment-averaged fluence rate that was consistent among treated tissue sites, despite instantaneous exposure to high fluence rate. Mild oxygen depletion after PDT was experienced at tissue sites with high pre-PDT S_t O₂ , which may suggest the presence of a treatment effect.

Extra-pleural pneumonectomy

The extra-pleural pneumonectomy (EPP) is a standardised surgical procedure born for pleural tuberculosis and later used in pleural cancer treatment, especially in malignant pleural mesothelioma (MPM). This systematic review aimed to focus on the actual overall EPP role in surgical oncology. The literature search was performed from January 1985 to January 2018 In PubMed, Embase, and Cochrane according to PRISMA protocol. The search was restricted to publications in English with the research words "extrapleural pneumonectomy", "malignant pleural mesothelioma", "pleural malignancies". The results were then filtered focusing only on papers with series of patients treated with EPP, for mesothelioma and non-mesothelioma malignancies. The search was restricted to publications in English. We found a 5-year overall survival (OS) ranging from 0 to 78%. The peri-operative mortality and morbidity ranged from 0 to 11.8% and 0 to 82.6%, respectively. The most represented and described post-operative complications reported were ARDS, pericardial tamponade, cardiac herniation, pulmonary embolism, respiratory infections, respiratory failure, atrial arrhythmia, myocardial infarction. In referral centres and selected patients, EPP is a cytoreductive or radical surgical treatment in extended pleural malignancies. Prospective studies are needed to standardise the timing of the procedure in a multimodality treatment program, according to the oncological and functional indications, to keep an acceptable complications rate and post-operative quality of life status.

Prolonged post-recurrence survival following pleurectomy/decortication for malignant pleural mesothelioma

The present study analyzed surgical results in patients with malignant pleural mesothelioma (MPM) who underwent extrapleural pneumonectomy (EPP) or pleurectomy/decortication (P/D). Data for 44 patients who achieved macroscopic complete resection following neoadjuvant chemotherapy followed by EPP (n=29) or P/D (n=15) were reviewed. Patient demographics and oncological outcomes were compared between the EPP and P/D groups. The median overall (OS) and progression-free survival (PFS) times were 22 and 14 months, respectively. OS was significantly different between the EPP and P/D groups (median OS, 17 vs. 34 months; 5-year OS, 11 vs. 44%; P=0.019); no difference was noted in PFS (median PFS, 13 vs. 21 months; 5-year PFS, 11 vs. 17%; P=0.373). Univariate analysis demonstrated that epithelial histology (P=0.0003) and P/D (P=0.018) were significant favorable prognostic factors for OS. Using multivariate analysis, epithelial histology (P=0.001) remained the only significant factor. Post-recurrence survival (PRS) among all patients was significantly longer in the P/D group (median PRS, 3 vs. 20 months; 1.5-year PRS, 5 vs. 54%; P=0.003), even among patients with epithelial-type MPM (median PRS, 6 s vs. 20 months; 1.5-year PRS, 8 vs. 61%; P=0.012). Chemotherapy following recurrence (P=0.033) was significantly associated with superior PRS in multivariate analysis. Postoperative pulmonary function was significantly improved in the P/D group. In summary, P/D may be an alternative procedure to EPP for resectable MPM providing similar PFS and improved PRS.

Surgical Options for Malignant Mesothelioma: A Single-Center Experience

Background

We investigated the surgical outcomes of patients who underwent therapeutic surgery for malignant pleural mesothelioma (MPM) at a single center.

Methods

A retrospective review of 21 patients who underwent therapeutic surgery for MPM from January 2001 to June 2015 was conducted to assess their outcomes. The patients’ characteristics and postoperative course, including complications, mortality, overall survival, and recurrence-free survival, were analyzed.

Results

Of the 21 patients who underwent therapeutic surgery, 15 (71.4%) underwent extrapleural pneumonectomy, 2 pleurectomy (9.5%), and 4 excision (19.1 %). The median age was 57 years (range, 32–79 years) and 15 were men (71.4%). The mean hospital stay was 16 days (range, 1–63 days). Median survival was 14.3 months. The survival rate was 54.2%, 35.6%, and 21.3% at 1, 3, and 5 years, respectively. In patients’ postoperative course, heart failure was a major complication, occurring in 3 patients (14.3%). The in-hospital mortality rate was 2 of 21 (9.5%) due to a case of severe pneumonia and a case of acute heart failure.

Conclusion

A fair 5-year survival rate of 21.3% was observed after surgical treatment. Heart failure was a major complication in our cohort. Various surgical methods can be utilized with MPM, each with its own benefits, taking into consideration the severity of the disease and the comorbidities of the patient. Patients with local recurrence may be candidates for surgical intervention, with possible satisfying results.

Malignant mesothelioma as a difficult interdisciplinary problem

The authors of the present report review the etiology and clinical symptoms of malignant pleural mesothelioma (MPM) as well as diagnostic techniques (both radiological and biomarkers) used for its detection. Subsequently, they present methods of multimodal treatment (surgery, chemotherapy, and radiotherapy) recommended by the International Mesothelioma Interest Group (IMIG). Finally, they discuss complications and long-term results associated with these methods of MPM treatment.

New Concepts in the Treatment of Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive and generally incurable cancer. Current anti-MPM chemotherapy-based treatments are only marginally effective, and long-term survival remains an unmet goal. Nonetheless, in selected cases, personalized surgery-based multimodality treatments (MMT) have been shown to significantly extend survival. The design of MMT and selection of patients are challenging, and optimal results require accurate presurgical diagnosis, staging, and risk stratification. Further, meticulous surgical techniques and advanced radiation protocols must be applied. We review key principles and evolving concepts in the care of MPM patients with a focus on the expanding role of MMT in MPM.

Malignant pleural mesothelioma: single-institution experience of 101 patients over a 15-year period

BACKGROUND

Malignant pleural mesothelioma (MPM) is a rare but aggressive neoplasm that typically originates from the mesothelial surfaces of the pleural cavity. Exposure to asbestos is the principal etiological agent of MPM. The disease is characterized by difficult stage classification and limited consensus on therapeutic approach. We have evaluated the experience with MPM in the Antwerp University Hospital over the past 15 years.

METHODS

A database was created with all patients diagnosed with or treated for a MPM between 2001 and 2015. A total of 101 patients were included on which different survival analyses were performed combined with a reproduction of demographic, clinical, histologic and therapeutic data, and these were compared to literature data.

RESULTS

Vast majority of our 101 patients were male (80%) with a median age of 66 years at diagnosis with predominantly epitheloid histology (81%). Overall median survival was 18.3 months and overall 1-, 2- and 5-year survival rates were 68%, 37% and 7%, respectively. Kaplan-Meier analysis showed a non-significant difference in survival between the several best (b) TNM-stages (p = .356). A significant difference in survival was observed in patients undergoing surgery versus no surgery (p = .008), between the different histological types (p < .0001) and treatment with chemotherapy alone versus chemotherapy with surgery (p < .0001). Smoking at diagnosis and epitheloid histology have been identified as significant prognostic factors in the multivariate Cox regression model (HR 3.13 and 0.53, respectively).

CONCLUSION

Descriptive and survival analysis of our patient database confirmed the limitations of the current staging system and were concordant with literature regarding MPM.

Radio-immunotherapy and chemo-immunotherapy as a novel treatment paradigm in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm with poor outcome. Novel radical radiation techniques using intensity modulated radiation therapy (IMRT) have become an important component of therapy in mesothelioma. Immunotherapy also provides new therapeutic options. However, how best to integrate immunotherapy with standard therapy such as radiation, chemotherapy and surgery remains unknown. A change of paradigm from adjuvant normofractionation to induction accelerated hypofractionated hemithoracic radiation could provide a platform to combine immunotherapy due to the potential benefit of short course high dose radiation on the immune system. Immunotherapy can also be combined with chemotherapy. Although chemotherapy is generally considered immunosuppressive, some chemotherapeutic agents do induce cell death that can be immunogenic and stimulate a specific immune response against the tumor. Immunotherapy could also be used in between cycles of chemotherapy to limit tumor cell repopulation and optimize the results of both treatments. The integration of immunotherapy into a multimodality approach is opening new avenue of treatment for mesothelioma.

Localized malignant pleural sarcomatoid mesothelioma misdiagnosed as benign localized fibrous tumor

Localized malignant pleural mesothelioma (LMPM) is a rare tumor with good prognosis by surgical resection. We report an atypical case of malignant pleural sarcomatoid mesothelioma (SM) in an asymptomatic 65-year-old woman, who had no history of exposure to asbestos. She presented with a small pleural mass without pleural effusion and was misdiagnosed as a benign localized fibrous tumor (BLFT) on pathologic examination through a surgical tumor specimen. However, seven months later, the patient returned with serious cancerous symptoms. A large recurrent tumor mass was found within the chest wall invading at the old surgical resection site. SM, a subtype of LMPM, was confirmed with histopathogy and immunohistochemisty. In conclusion, malignant pleural mesothelioma (MPM) can present with typical radiologic finding similar to a BLFT, and has a wide histopathologic presentation in biopsy specimen. A thorough pathologic investigation should be attempted even when a pleural mass resembles benign, localized, and small on radiologic studies.

Multimodality therapy for malignant pleural mesothelioma: surgery plus chemoradiotherapy?

Malignant pleural mesothelioma, well known for its association with asbestos exposure, is an aggressive cancer of the pleura with poor prognosis if left untreated. There is no defined standard of care, but with curative surgery-based multimodality therapy, long-term survival has been documented. In addition to radiation and/or chemotherapy, multimodality therapy includes one of two operations (extrapleural pneumonectomy or radical pleurectomy/decortication) performed with the goal of resecting all gross disease. Ongoing trials are evaluating various treatment strategies involving radical resection, chemotherapy, radiation, intracavitary chemotherapy, photodynamic therapy and immunologic/biologic agents. Improvement in early diagnosis, targeted treatment and adjuvant therapy to control micrometastatic disease are needed to improve outcomes for patients with this challenging disease.

The impact of pleural disease on the management of advanced ovarian cancer

Malignant pleural effusion is the most common site of stage IV ovarian cancer. A positive cytology is required for a stage IVA diagnosis. Unfortunately, the accuracy rate of pleural cytology remains low. A number of factors have been identified as prognostic for clinical outcomes in patients with epithelial ovarian cancer (EOC), the International Federation of Gynaecology and Obstetrics (FIGO) stage and residual tumor after debulking surgery being the most widely reported. Thereby careful selection of patients is crucially important, yet no preoperative predictor has proven sufficiently reliable to predict surgical outcome. The authors present a review of the literature on stage IV ovarian cancer specifically focusing on prognostic value of FIGO stage, preoperative workup, role of video-assisted thoracic surgery and maximal cytoreductive surgery.

Ki67 index is an independent prognostic factor in epithelioid but not in non-epithelioid malignant pleural mesothelioma: a multicenter study

Background:

Estimating the prognosis in malignant pleural mesothelioma (MPM) remains challenging. Thus, the prognostic relevance of Ki67 was studied in MPM.

Methods:

Ki67 index was determined in a test cohort of 187 cases from three centres. The percentage of Ki67-positive tumour cells was correlated with clinical variables and overall survival (OS). The prognostic power of Ki67 index was compared with other prognostic factors and re-evaluated in an independent cohort (n=98).

Results:

Patients with Ki67 higher than median (>15%) had significantly (P<0.001) shorter median OS (7.5 months) than those with low Ki67 (19.1 months). After multivariate survival analyses, Ki67 proved to be—beside histology and treatment—an independent prognostic marker in MPM (hazard ratio (HR): 2.1, P<0.001). Interestingly, Ki67 was prognostic exclusively in epithelioid (P<0.001) but not in non-epithelioid subtype. Furthermore, Ki67 index was significantly lower in post-chemotherapy samples when compared with chemo-naive cases. The prognostic power was comparable to other recently published prognostic factors (CRP, fibrinogen, neutrophil-to-leukocyte ratio (NLR) and nuclear grading score) and was recapitulated in the validation cohort (P=0.048).

Conclusion:

This multicentre study demonstrates that Ki67 is an independent and reproducible prognostic factor in epithelioid but not in non-epithelioid MPM and suggests that induction chemotherapy decreases the proliferative capacity of MPM.

Extrapleural pneumonectomy for malignant mesothelioma: an Italian multicenter retrospective study

BACKGROUND

This study assessed perioperative outcome and long-term survival in a large series of patients with malignant pleural mesothelioma who underwent extrapleural pneumonectomy (EPP) to identify prognostic factors allowing better patient selection.

METHODS

We retrospectively collected data from nine referral centers for thoracic surgery in Italy. Perioperative outcome and survival data were available for 518 malignant pleural mesothelioma patients (84.4% with epithelial tumors, 68.0% with pathologic stage 3 disease) who underwent EPP with intention-to-treat (R0/R1) between 2000 and 2010. Induction chemotherapy was administered in 271 patients (52.3%) and adjuvant therapy in 373 patients (72.0%), including radiotherapy in 213 patients (41.1%), adjuvant chemotherapy in 43 patients (8.3%), and both in 117 patients (22.6%).

RESULTS

In all, 136 patients (26.3%) had major complications after EPP, and 36 (6.9%) died within 90 days after surgery. The median overall survival was 18 months, with a 1-, 2-, and 3-year overall survival of 65%, 41%, and 27%, respectively. At multivariable analysis adjusted for age and disease stage, male sex (hazard ratio [HR] 1.47, 95% confidence interval [CI]: 1.12 to 1.92), nonepithelial histology (HR 1.96, 95% CI: 1.48 to 2.58), and trimodality treatment using induction chemotherapy (HR 0.61, 95% CI: 0.43 to 0.85) were significantly associated with survival. Development of a major complication also significantly worsened outcome (HR 1.85, 95% CI: 1.37 to 2.50).

CONCLUSIONS

The success of EPP in the context of a multimodality treatment depends on a series of patient characteristics. Female patients, patients with epithelial tumors, and patients who received induction chemotherapy will best benefit from EPP.

Extrapleural pneumonectomy or pleurectomy/decortication for malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is associated with a very poor prognosis. Unlike other solid tumors, any type of planned surgery for MPM would be cytoreductive rather than radical. There are two types of surgery for MPM. Extrapleural pneumonectomy (EPP) involves en bloc resection of the lung, pleura, pericardium, and diaphragm. Pleurectomy/decortication (P/D) is a lung-sparing surgery that removes only parietal/visceral pleura. In comparison with EPP, P/D is theoretically less radical but is associated with less perioperative mortality/morbidity and less postoperative deterioration of cardiopulmonary function. It still remains unclear which surgical technique is superior in terms of the risk/benefit ratio. In this context, selection between EPP and P/D has been a matter to debate.

[Helical tomotherapy in the treatment of malignant pleural mesothelioma: The impact of low doses on pulmonary and oesophageal toxicity]

PURPOSE

To evaluate the adjuvant treatment of malignant pleural mesothelioma by helical tomotherapy and the impact of low doses on esophageal and pulmonary toxicity.

PATIENTS AND METHODS

Between June 2007 and May 2011, 29 patients diagnosed with malignant pleural mesothelioma received adjuvant radiotherapy by helical tomotherapy. The median age was 63 years (34-72). Histologically, 83 % of patients had epithelioid malignant pleural mesothelioma. Clinically, 45 % of patients were T3 and 55 % N0. Eighty six percent of the patients were treated by extrapleural pneumonectomy and 35 % received neoadjuvant chemotherapy with platinum and pemetrexed. The median dose in the pneumonectomy cavity was 50Gy at 2Gy/fraction.

RESULTS

The mean follow-up was 2.3 years after diagnosis. Overall survival at 1 and 2 years was 65 and 36 % respectively. The median survival from diagnosis was 18 months. Median lung volumes receiving 2, 5, 10, 13, 15 and 20Gy (V2, V5, V10, V13, V15 and V20) were 100, 98, 52, 36, 19 and 5 %. The median of the mean remaining lung dose was 11Gy. Two patients died of pulmonary complications, three patients had grade 3 lung toxicity, while esophageal grade 3-4 toxicity was observed in three other patients. No significant impact of clinical characteristics and dosimetric parameters were found on pulmonary toxicity, however a V10≥50 %, a V15≥15 % and mean lung dose of 10Gy or more had a tendency to be predictive of pulmonary toxicity (P<0.1). Moreover, in our analysis, the mean lung dose seems to have a significant impact on esophageal toxicity (P=0.03) as well as low doses to the controlateral lung: V5, V10 and V13 (P<0.05).

CONCLUSION

Helical tomotherapy is a promising technique in the multimodality treatment of malignant pleural mesothelioma. Low doses received by the contralateral lung appear to be the limiting factor. A dosimetric comparison with volumetric modulated arctherapy techniques would be interesting in this setting.

Radical pleurectomy/decortication followed by high dose of radiation therapy for malignant pleural mesothelioma. Final results with long-term follow-up

PURPOSE

We have previously shown the feasibility of delivering high doses of radiotherapy in malignant pleural mesothelioma (MPM) patients who underwent radical pleurectomy/decortication (P/D) or surgical biopsy. In this report, we present the long-term results of MPM patients treated with radical P/D followed by high doses of radiotherapy.

METHODS AND MATERIALS

Twenty consecutive MPM patients were enrolled in this prospective study and underwent radical P/D followed by high dose radiotherapy. The clinical target volume was defined as the entire hemithorax excluding the intact lung. The dose prescribed was 50 Gy in 25 fractions. Any FDG-avid areas or regions of particular concern for residual disease were given a simultaneous boost to 60 Gy. Nineteen patients received cisplatin/pemetrexed chemotherapy. Kaplan-Meier analysis was used to calculate rates of overall survival (OS), progression-free survival (PFS), and loco-regional control (LRC).

RESULTS

The median follow-up was of 27 months. The median OS and PFS were 33 and 29 months, respectively. The median LRC was not reached. The Kaplan-Meier estimates of OS at 2 and 3 years were 70% and 49%, respectively. The estimates of PFS at 2 and 3 years were 65% and 46%, respectively. The estimates of LRC at 2 and 3 years were 68% and 59%, respectively. The predominant pattern of failure was distant: 7 patients developed distant metastases as the first site of relapse, whereas only 3 patients experienced an isolated loco-regional recurrence. No fatal toxicity was reported. Five Grades 2-3 pneumonitis were documented.

CONCLUSIONS

High dose radiation therapy following radical P/D led to excellent loco-regional control and survival results in MPM patients. A median OS of 33 months and a 3-year OS rate of 49% are among the best observed in recent studies, supporting the idea that this approach represents a concrete therapeutic option for malignant pleural mesothelioma.

Role of new radiation techniques in the treatment of pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm arising from the surface serosal cells of the pleural cavity. Surgery remains the main therapeutic standard in the treatment of MPM with the goal of complete gross cytoreduction of the tumor. Because MPM is a diffuse disease affecting the entire mesothelial lining of the hemithorax, surgery alone can rarely achieve adequate tumor-free resection margins. The surgical choices are pleurectomy/decortication (P/D) or extrapleural pneumonectomy (EPP). Radiotherapy (RT) is usually applied postoperatively with the aim to improve local control. However, the efficacy of RT is limited by the large volume of the target to be irradiated (tumor and pleural cavity) and the radiosensitivity of the nearby organs (heart, liver, lung, spinal cord, and esophagus). These factors have historically limited the effective radiation doses that can be given to the patient. There is no role for radical RT alone, but the role of RT as part of multimodality therapy is discussed. After EPP adjuvant RT to the entire hemithorax can reduce the recurrence rate and is well tolerated if strict limits to the dose to contralateral lung are applied: the V20 and V5 (the percent volume of the lung receiving more than 20Gy and 5Gy of radiation) correlate with increased lung toxicity. The use of modern sophisticated techniques allows good target coverage, more conformal high dose delivery, and clinically relevant normal tissue sparing.

[Surgical aspects of malignant pleural mesothelioma: from the perspective of pathology]

The increased use of asbestos in Germany in the mid 1970s led occupational physicians, pulmonologists, thoracic surgeons and pathologists to the expectation of an increasing incidence and mortality in patients with pleural mesothelioma up to 2020. Prerequisite for curative surgery is a pathological anatomical tumor diagnosis on the basis of a biopsy and accurate tumor staging. In order to achieve reproducible results in the assessment of malignant pleural diseases, the pathological anatomical diagnosis of malignant pleural mesothelioma should be made according to the guidelines of the international mesothelioma interest group (IMIG). Currently used multimodal thoracic surgery therapeutic concepts present new challenges and problems to the pathological anatomical diagnosis and are discussed in this article.

Tomotherapy after pleurectomy/decortication or biopsy for malignant pleural mesothelioma allows the delivery of high dose of radiation in patients with intact lung

INTRODUCTION

This study aimed to assess the safety of high doses of radiation delivered with tomotherapy to the intact lung after radical pleurectomy/decortication or biopsy for malignant pleural mesothelioma (MPM).

METHODS

Twenty-eight patients were enrolled in this prospective study and underwent adjuvant or definitive tomotherapy after radical pleurectomy/decortication (n = 20) or pleural biopsy (n = 8) for MPM. The dose prescribed to the planning target volume, defined as the entire hemithorax, including chest-wall incisions and drain sites and excluding the intact lung, was 50 Gy delivered in 25 fractions. All patients underwent fluorodeoxyglucose-positron emission tomography for staging after surgery. Any fluorodeoxyglucose-avid areas or regions of particular concern for residual disease were given a simultaneous boost of radiotherapy to 60 Gy. Specific lung dosimetric parameters were reported. Toxicity was graded using the modified Common Toxicity Criteria version 3.0.

RESULTS

The median follow-up was of 19 months (range, 6-29 months). Five patients (17.8%) experienced severe respiratory symptoms corresponding to grade 2 pneumonitis in three cases, and grade 3 pneumonitis in two cases. No fatal respiratory toxicity was reported. Controlateral lung V5 was strongly correlated with the risk of pneumonitis. Patients who developed grade 2 and 3 pneumonitis had a higher controlateral lung V5 (mean V5=32%) than those without pneumonitis (mean V5=17%) (p=0.002). Other two grade 3 toxicities were registered: one severe pain to the chest wall, and one severe thrombocytopenia.

CONCLUSIONS

Tomotherapy allows the safe delivery of high dose of radiation to the hemithorax of MPM patients with intact lung.

What is the survival after surgery for localized malignant pleural mesothelioma?

A best evidence topic in thoracic surgery was written according to a structured protocol. This was with the purpose of assisting our management of patients with localized malignant mesothelioma of the pleura (LMM). Although the terminology is used inconsistently, this variant has been formally defined by the WHO as a distinct entity defined as localized disease histologically identical to the diffuse form but without any evidence of pleural spread. Treatments for LMM include different combinations of surgery, chemotherapy and radiotherapy. There is an impression that LMM may have a better outcome than the commoner diffuse form of malignant mesothelioma that has been reported to have a survival between 8 and 14 months. In order to advise our patients on prognosis, we studied the duration of survival after surgical resection of LMM. A total of 150 papers were found, of which 16 represented the best evidence to answer the question. The authors, journal, date, country of publication, study type, relevant outcomes and results of these papers are tabulated. It is difficult to combine the results of these 16 papers because both treatments and results are reported differently. Some report median survival (range: 11.6-36 months) and others disease-free survival (range: 0 months to 11 years). Median survival to the longest follow-up was 29 months when calculated by pooling data from informative papers using the Kaplan-Meier method. Our review suggests that survival in LMM is longer than that generally quoted for the more common diffuse form of malignant mesothelioma. Hence, aggressive treatment of LMM may be reasonable in appropriate patients.

CD147 immunohistochemistry discriminates between reactive mesothelial cells and malignant mesothelioma

Malignant mesothelioma (MM) is a rare form of cancer. Its histopathological diagnosis is very difficult, as it exhibits a number of different appearances that can be misinterpreted as metastatic invasion or atypical hyperplasia. Thus, there is an urgent need to identify adequate markers to distinguish between benign and malignant cells, allowing the implementation of appropriate therapies and, possibly, specific directed therapies. MM, like other tumors, show an increase in glucose uptake, due to high rates of glycolysis, inducing an intracellular overload of acids. In this context, monocarboxylate transporters (MCTs) emerge as important players, by mediating the transmembranar co-transport of lactate with a proton, thereby, regulating pH and allowing continuous glycolysis. Importantly, proper MCT expression and activity depend on its co-expression with a chaperone, CD147, which is associated with poor prognosis in cancer. Twenty-two samples including reactive mesothelial cells, MM, and atypical mesothelial hyperplasias were evaluated for immunoexpression of MCT1, MCT4, and CD147. Expression of these proteins was compared with GLUT1 as a new promising marker for MM. Although MCT isoforms were not differentially expressed in the two types of cytological specimens, CD147, as GLUT1, was almost exclusively expressed in MM. Both MCT1 and MCT4 are not able to discriminate between mesothelial reactive cells and mesothelial malignant cells, while CD147 was able to distinguish these two proliferations. If confirmed, besides being a good marker for identification of MM, CD147 may also be a target for therapeutical strategies in this rare type of tumor.

Radical pleurectomy and intraoperative photodynamic therapy for malignant pleural mesothelioma

BACKGROUND

Radical pleurectomy (RP) for mesothelioma is often considered either technically unfeasible or an operation limited to patients who would not tolerate a pneumonectomy. The purpose of this study was to review our experience using RP and intraoperative photodynamic therapy (PDT) for mesothelioma.

METHODS

Thirty-eight patients (42-81 years) underwent RP-PDT. Thirty five of 38 (92%) patients also received systemic therapy. Standard statistical techniques were used for analysis.

RESULTS

Thirty seven of 38 (97%) patients had stage III/IV cancer (according to the American Joint Committee on Cancer [AJCC manual 7th Edition, 2010]) and 7/38 (18%) patients had nonepithelial subtypes. Macroscopic complete resection was achieved in 37/38 (97%) patients. There was 1 postoperative mortality (stroke). At a median follow-up of 34.4 months, the median survival was 31.7 months for all 38 patients, 41.2 months for the 31/38 (82%) patients with epithelial subtypes, and 6.8 months for the 7/38 (18%) patients with nonepithelial subtypes. Median progression-free survival (PFS) was 9.6, 15.1, and 4.8 months, respectively. The median survival and PFS for the 20/31 (64%) patients with N2 epithelial disease were 31.7 and 15.1 months, respectively.

CONCLUSIONS

It was possible to achieve a macroscopic complete resection using lung-sparing surgery in 97% of these patients with stage III/IV disease. The survival we observed with this approach was unusually long for the patients with the epithelial subtype but, interestingly, the PFS was not. The reason for this prolonged survival despite recurrence is not clear but is potentially related to preservation of the lung or some PDT-induced effect, or both. We conclude that the results of this lung-sparing approach are safe, encouraging, and warrant further investigation.

Recommendations for uniform definitions of surgical techniques for malignant pleural mesothelioma: a consensus report of the international association for the study of lung cancer international staging committee and the international mesothelioma interest group

INTRODUCTION

Extrapleural pneumonectomy has been well defined; however, surgeons vary regarding the surgical extent and goals of "pleurectomy/decortication" (P/D). We explored mesothelioma surgeons' concepts of P/D with the aim of unifying surgical nomenclature.

METHODS

A web-based survey was administered to surgeons who operated on malignant pleural mesothelioma (MPM) for diagnosis, staging, palliation, or cytoreduction. One hundred thirty surgeons from 59 medical centers were included. Surgeons who did not perform surgery for MPM within the last year were excluded.

RESULTS

There were 62 (48%) respondents from 39 medical centers in 14 countries. The mean number of patients with MPM seen annually at each medical center was 46, and the mean annual number of cytoreductive procedures performed per surgeon was 8. Most (88%) agreed that the goal of cytoreductive surgery should be macroscopic complete resection of tumor. P/D was defined as resection of parietal and visceral pleura with the aim of achieving macroscopic complete resection by 72% of respondents. If the diaphragm or pericardium required resection, 64% preferred the term "radical P/D," whereas "P/D" (40%) or "total pleurectomy" (39%) was preferred if these structures were not removed. Most surgeons believed that extrapleural pneumonectomy (90%) or "radical P/D" (68%) could provide adequate cytoreduction, whereas only 23% thought that P/D could.

CONCLUSIONS

There was significant variation regarding surgical nomenclature for procedures for MPM. The International Staging Committee of the International Association for the Study of Lung Cancer and the International Mesothelioma Interest Group recommend that P/D should aim to remove all macroscopic tumor involving the parietal and visceral pleura and should be termed "extended" P/D when the diaphragm or pericardium is resected.

Photodynamic therapy for malignant pleural mesothelioma: the future of treatment?

Malignant pleural mesothelioma is a deadly incurable cancer, with a median survival of approximately 9 months. The best available chemotherapy, arguably the standard of care, only yields a 40% response rate and an 11-week extension in median survival. Surgery, the modality most likely to be associated with prolonged remission, remains investigational and must always be combined with other modalities in an effort to treat the microscopic disease that will remain even after the most aggressive operations. One such modality, photodynamic therapy, is a light-based cancer treatment that has features making it particularly well suited as a component of a surgery-based multimodal treatment plan. Utilizing intraoperative photodynamic therapy has enabled development of a less drastic surgical procedure that is also yielding some encouraging survival results. A unique aspect of photodynamic therapy is its stimulation of a tumor-directed immune response, a feature that offers promise for designing future treatments.

Multimodality Imaging Review of Malignant Pleural Mesothelioma Diagnosis and Staging

Early diagnosis and accurate disease staging in patients with malignant pleural mesothelioma (MPM) are essential in classifying such patients into prognostic subgroups to allow delivery of stage-specific therapies. This review addresses the current status of multimodality imaging in the diagnosis and staging of MPM. Clinical, research, and future directions in computed tomography (CT), magnetic resonance imaging, and PET/CT diagnosis and staging of MPM are discussed, including the use of novel PET probes. The article concludes with important take-home messages summarized as the pearls and pitfalls of each diagnostic modality in the diagnosis and staging of patients with MPM.