The role of radiotherapy in the treatment of malignant pleural mesothelioma

What's Current and What's New in Mesothelioma?

Malignant mesothelioma is a rare disease with limited treatment options. In malignant pleural mesothelioma (MPM), radical trimodality approaches, including surgery, radiotherapy and systemic chemo- and immunotherapy, have been delivered in some countries but remain controversial due to a lack of randomised evidence. Even in the unresectable scenario, surgery and radiotherapy play an important role in managing pleural effusions and pain, which may optimise wellbeing and maintain performance status. From the systemic treatment point of view, the recent incorporation of anti-angiogenics and, more importantly, immunotherapy has changed the standard of care in a space where chemotherapy with platinum and pemetrexed was the only therapeutic intervention with demonstrated benefits in overall survival. Histology is essential in determining an initial treatment plan as non-epithelioid MPMs may have a higher substantial survival improvement with dual immunotherapy compared with chemotherapy, whereas chemotherapy remains an option for epithelioid MPM; however, predictive biomarkers for systemic therapy are not entirely validated to guide the selection, as a subgroup of MPM patients might not benefit from immunotherapy. This overview approaches how the overall management of mesothelioma is evolving to incorporate the recent changes in the standards of care.

Isolated Chest Wall Implantation of Non-Small Cell Lung Cancer after Fine-Needle Aspiration: A Case Report and Review of the Literature

Percutaneous fine-needle aspiration biopsy (FNAB) is a well-established and useful procedure in the diagnosis of lung squamous cell carcinoma (LSCC). Tumor seeding has been shown to be a potential risk. We report the case and management of a 78-year-old patient affected by LSCC who developed a chest wall metastasis in a straight line from the primary lesion along the FNAB needle track. Although tumor seeding after FNAB is a rare but possible complication, we suggest that careful examination for implantation (with periodical CT scans) should be performed for at least three years after FNAB.

Systematic review of trimodality therapy for patients with malignant pleural mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is an aggressive form of cancer arising from the pleural mesothelium. Trimodality therapy (TMT) involving extrapleural pneumonectomy with neoadjuvant or adjuvant chemotherapy and adjuvant radiotherapy is a recognized treatment option with a curative intent. Despite encouraging results from institutional studies, TMT in the treatment of MPM remains controversial. The present systematic review aims to assess the safety and efficacy of TMT in the current literature.

METHODS

A systematic review was performed using five electronic databases from 1 January 1985 to 1 October 2012. Studies were selected independently by two reviewers according to predefined selection criteria. The primary endpoint was overall survival. Secondary endpoints included disease-free survival, disease recurrence, perioperative morbidity and length of stay.

RESULTS

Sixteen studies were included for quantitative assessment, including one randomized controlled trial and five prospective series. Median overall survival ranged from 12.8-46.9 months. Disease-free survival ranged from 10-16.3 months. Perioperative mortality ranged from 0-12.5%. Overall perioperative morbidity ranged from 50-82.6% and the average length of stay was 9-14 days.

CONCLUSIONS

Outcomes of patients who underwent TMT in the current literature appeared to be inconsistent. Four prospective series involving a standardised treatment regimen with neoadjuvant chemotherapy indicated encouraging results based on intention-to-treat analysis. However, a small study assessing the feasibility of conducting a randomized controlled trial for TMT versus conservative treatment reported poor short- and long-term outcomes for patients who underwent pneumonectomy. Overall, results of the present systematic review suggest TMT may offer acceptable perioperative outcomes and long-term survival in selected patients treated in specialized centers.

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.

Opioids in pain management of mesothelioma and lung cancer patients

BACKGROUND

Lung cancer and mesothelioma are malignant tumors with generally dismal prognosis and therefore palliative pain treatment constitutes a challenge for the clinician.

OBJECTIVES

The aim of this study was to compare the outcomes of pain treatment with opioids among mesothelioma and lung cancer patients treated for palliation and assess factors which confound to optimal treatment.

PATIENTS AND METHODS

A sub-cohort of 373 lung cancer and 22 mesothelioma patients was identified in multi-center European Pharmacogenetic Opioid Study (EPOS) cohort. A nested case-control (1:4) setting was designed to estimate the pain and other covariates distinguishing 22 mesothelioma- (= cases) and 88 lung cancer patients (controls), analyzed using univariate- and multivariate conditional (fixed-effects) logistic regression models.

RESULTS

The mean total daily dose of opioids varied from 30.0 to 960.0 mg (mean 275, median 160 mg, SD 293) in mesothelioma, and from 10 to 5072 mg (mean 414, median 175, SD 788) in lung cancer patients (p = 0.420). In both groups, pain was mostly experienced as moderate and severe and it was frequently accompanied by depression, poor sleep, anxiety and fatigue. Four mesothelioma patients (18%) and seven lung cancer patients (10%) experienced complete pain relief with opioids by self-assessment. Assessments of pain severity by the patients and their physicians deviated significantly in mesothelioma (p = 0.039 McNemar test), as well as in lung cancer (p = 0.0001). In conditional logistic regression, no significant differences were found in distribution of pain covariates between lung cancer and mesothelioma patients.

CONCLUSION

Pain perception by the patients was associated frequently with other symptoms and complete pain control with opioids was achieved only with minority of patients both with mesothelioma and advanced lung cancer. Adequate pain control requires continuous monitoring and tailoring the dose to patient's individual needs and tolerance, recognition of accompanying symptoms such as depression and poor sleep, and their management.

Radiotherapy applications of patients with malignant mesothelioma: A single center experience

BACKGROUND

In the management of malignant pleural mesothelioma, radiotherapy has been used for the purpose of prophylaxis to reduce the incidence of recurrence at surgical insertion sites or palliate the symptoms.

AIM

The purpose of the study was to evaluate the techniques and effectiveness of radiotherapy in malignant pleural mesothelioma.

MATERIALS AND METHODS

Forty-four (18 female, 26 male) patients diagnosed with malignant pleural mesothelioma were retrospectively evaluated. All patients had surgery or thoracoscopic biopsy for diagnosis, staging or treatment and all received palliative or prophylactic radiotherapy. Fifty-seven percent of the patients received chemotherapy.

RESULTS

Prophylactic radiation was applied to 27 patients with 4-15 MeV electron energies. The median radiotherapy dose was 30 Gy with 3 Gy daily fraction dose. During treatment, 12 patients had grade 1 erythema according to the RTOG scale. In 3 (12%) patients, a local failure at treatment field was observed. Palliative radiotherapy was applied to 17 patients for pain palliation. The median radiation dose was 40 Gy with 2 Gy daily fraction dose by using 6-18 MV photon and/or 4-12 MeV electron energies. Two patients had grade 1 erythema and one patient had grade 2 odynophagy according to the RTOG scale. For 10 (59%) patients, palliation of chest pain was delivered. No late toxicity was observed for all cases.

CONCLUSION

Our experience showed that prophylactic and palliative radiotherapy are effective and safe therapy modalities in malignant pleural mesothelioma in preventing seeding metastasis at intervention sites or relieving pain. Prospective randomized studies are still needed to determine the benefits of radiotherapy application and to indicate optimum dose schemes.

Respiratory chest pain: diagnosis and treatment

Chest pain from respiratory causes is a common complaint and may indicate the presence of a serious or even life-threatening pathologic condition. Most chest pains are the result of irritation or inflammation of the parietal pleura, as the visceral pleura is insensate, although pain may arise from direct malignant invasion or trauma to the chest wall. Rapid recognition with appropriate understanding of the anatomy and physiology of chest pain from respiratory causes is vital to ensure timely and appropriate therapy.

Prophylactic radiotherapy to intervention sites in mesothelioma: a systematic review and survey of UK practice

BACKGROUND AND PURPOSE

Patients with malignant pleural mesothelioma (MPM), who undergo chest instrumentation, may develop seeding at the site of intervention, leading to subcutaneous tumour. This is believed to be reduced by the common practice of prophylactic irradiation to intervention tracts (PIT). However, evidence to support PIT is currently inadequate and contentious.

MATERIALS AND METHODS

We carried out a systematic search of published literature for articles relating to the incidence of chest wall intervention tract metastases and the use of PIT in mesothelioma. In addition, a survey of current practice was conducted in 54 UK oncology centres.

RESULTS

Fourteen studies revealed an incidence of chest wall intervention tract metastases of 0-48% with a trend toward a higher rate of metastases for more invasive procedures. Three randomised controlled trials (RCTs), two prospective non-randomised studies and five retrospective series met the eligibility criteria to evaluate the role of PIT in MPM. Of the three RCTs, two did not support the use of PIT. None of the RCTs included patients who had received systemic chemotherapy. Of the oncology centres responding to the survey, 75% practiced PIT, and 80% would be interested in a trial to determine the efficacy of PIT.

CONCLUSIONS

No consensus has been reached to support the use of PIT. However, most centres in the UK still offer PIT. There was widespread interest in a randomised controlled trial to establish PIT efficacy in the era of effective systemic chemotherapy for malignant pleural mesothelioma.

Prevention of malignant seeding at drain sites after invasive procedures (surgery and/or thoracoscopy) by hypofractionated radiotherapy in patients with pleural mesothelioma

INTRODUCTION

Literature data show that mesothelioma cells can implant along the surgical pathway of invasive procedures such as thoracotomy and thoracoscopy. We investigated the use of hypofractionated radiotherapy for preventing such malignant seeding.

MATERIAL AND METHODS

Thirty-two consecutive patients diagnosed with pleural mesothelioma were included in the present retrospective study. All patients underwent surgery and/or thoracoscopy for diagnosis, staging or talc pleurodesis. They were treated with electron external beam radiation therapy (21 Gy in 3 fractions over 1 week), directed to the surgical pathway after the invasive procedure. After completion of radiation treatment, 20 of 32 patients (63%) underwent chemotherapy.

RESULTS

After a mean follow-up of 13.6 months (range 3-41) from the end of radiation therapy, no patient had tumour progression in the treated area. The treatment was well tolerated, as only erythema grade I (Radiation Therapy Oncology Group, RTOG, scale) was noted in 11 patients. Seventeen patients died of disease with local progression after a mean survival time of 12.6 months (range 3-27); thirteen patients are alive with disease after a mean follow-up of 13.9 months (range 4-41); two patients are alive without evidence of disease after a mean follow-up of 16.50 months (range 6-27).

DISCUSSION

The present study shows the efficacy and safety of local radiotherapy in preventing malignant seeding after thoracoscopy in patients with pleural mesothelioma although larger prospective trials are probably still needed to validate this treatment approach.

Malignant mesothelioma

Malignant mesothelioma is a fatal asbestos-associated malignancy originating from the lining cells (mesothelium) of the pleural and peritoneal cavities, as well as the pericardium and the tunica vaginalis. The exact prevalence is unknown but it is estimated that mesotheliomas represent less than 1% of all cancers. Its incidence is increasing, with an expected peak in the next 10–20 years. Pleural malignant mesothelioma is the most common form of mesothelioma. Typical presenting features are those of chest pain and dyspnoea. Breathlessness due to a pleural effusion without chest pain is reported in about 30% of patients. A chest wall mass, weight loss, sweating, abdominal pain and ascites (due to peritoneal involvement) are less common presentations. Mesothelioma is directly attributable to occupational asbestos exposure with a history of exposure in over 90% of cases. There is also evidence that mesothelioma may result from both para-occupational exposure and non-occupational "environmental" exposure. Idiopathic or spontaneous mesothelioma can also occur in the absence of any exposure to asbestos, with a spontaneous rate in humans of around one per million. A combination of accurate exposure history, along with examination radiology and pathology are essential to make the diagnosis. Distinguishing malignant from benign pleural disease can be challenging. The most helpful CT findings suggesting malignant pleural disease are 1) a circumferential pleural rind, 2) nodular pleural thickening, 3) pleural thickening of > 1 cm and 4) mediastinal pleural involvement. Involvement of a multidisciplinary team is recommended to ensure prompt and appropriate management, using a framework of radiotherapy, chemotherapy, surgery and symptom palliation with end of life care. Compensation issues must also be considered. Life expectancy in malignant mesothelioma is poor, with a median survival of about one year following diagnosis.

Malignant mesothelioma 2008

PURPOSE OF REVIEW

Mesothelioma is an aggressive malignancy of the pleura with poor survival. There will be approximately 3000 cases of mesothelioma in the United States annually. Multimodality treatment including neoadjuvant chemotherapy in selected individuals followed by extrapleural pneumonectomy and radiation has been studied in recent trials for its effects on disease free and overall survival This review provides a general overview of malignant mesothelioma with a summary of the most significant articles from within the past year as well as from the past.

RECENT FINDINGS

Areas of recent interest include the evaluation of osteopontin and mesothelin as new tumor markers for mesothelioma. New phase III trials have been performed to evaluate the use of combined chemotherapy regimens.

SUMMARY

Malignant mesothelioma is a very difficult malignancy to treat. Patients with the disease usually have an occupational asbestos exposure, and in some, viral exposure with SV40. There have been many historical treatments including combinations of local control with surgery and radiation as well as attempts to prevent systemic failure with chemotherapy. Novel therapies including intrapleural chemotherapy, photodynamic therapy and hyperthermic perfusion have also been used with some success. Finally there are several attempts at immunomodulating and targeted treatments, which are in phase I/II trials.

Primary Malignant Mesothelioma of the Abdominal Wall: Complete Response with Radiotherapy Alone

A 72-year-old female was found to have a large primary mesothelioma of the right flank musculature. She was not felt to be surgically resectable and was treated with 3D-conformal radiotherapy alone to a total dose 70 Gy. She had a complete response with no evidence of local progression when two years after treatment imaging revealed lung metastases, confirmed on biopsy. The present case suggests that radiotherapy alone can provide sustained local control of mesothelioma.

[Malignant pleural mesothelioma: interrogations and hopes concerning the expected epidemic]

Malignant pleural mesothelioma (MPM) is a rare incurable tumor. Interest in MPM has increased in recent years due to a steadily increasing incidence subsequent to the intensive use of asbestosis, the main causal agent, but also due to better awareness in the political and scientific communities faced with a serious public health issue. Our knowledge of MPM has improved regularly in terms of pathologic diagnosis and the mechanisms underlying the mesothelial carcinogenesis. MPM is also the subject of many technological innovations as illustrated by the recent identification of new biological markers, access to metabolic imaging, and clinical research on targeted treatments. Proper management implies the participation of the general population since the implementation of administrative procedures for social indemnities. In 2007, a more aggressive therapeutic approach is becoming common practice with the use of radiotherapy and the emergence of the concept of multimodal care centered on wide pleuropneumonectomy. These advances create real hope for improvement, but also many interrogations since no standard treatment protocol has been clearly identified.