Two major procedures are used in the surgical treatment of mesothelioma: extrapleural pneumonectomy (EPP) and pleurectomy/decortication (PD). An EPP involves the complete removal of the affected lung and pleura, as well as a partial or total resection of the diaphragm and pericardium. A PD is a similar, but less radical procedure, where the lung itself is spared, but both the parietal and the visceral pleura are removed and possibly the diaphragm and pericardium. There has been considerable historical controversy surrounding the appropriate conditions for the deployment of either procedure, but recent research seems to indicate that PD is more appropriate for early-stage pleural mesothelioma, while EPP, because of the greater amount of gross tissue that is removed, is more appropriate for late stage disease and presentations with a significant local spread. EPP, however, also had a reputation for significant surgical side effects. It was often characterized by high numbers of post-surgical mortality and morbidity and while improvements in technique have certainly reduced the number and the severity of common complications, the procedure is still quite radical, so great care must be taken to ensure the best patient outcomes.

A number of studies on the outcomes of extrapleural pneumonectomy have recently been published. Researchers from the Austria are the latest to publish their findings on EPP.

Overview of the Study

The authors undertook a retrospective analysis of all patients who underwent an extrapleural pneumonectomy for pleural mesothelioma between 1994 and 2005 at the Medical University of Vienna. Of the 49 cases examined, 10 were female patients and 39 were males. 24 patients underwent a left-sided EPP, while 25 right-sided procedures were performed. Histologically, epitheloid mesothelioma was the most common subtype of the study, with 30 presentations. There were 15 cases of biphasic mesothelioma and four sarcomatoid cases. 13 patients received induction chemotherapy and 14 received adjuvant chemotherapy. All cases were examined for mortality, side effects and overall survival time.

During EPP, the entire lung, as well as the pleura, pericardium and diaphragm were resected and a mediastinal lymph node dissection was regularly performed as well. The patients were tracked post-surgery using CT scans every three to six months and underwent cytological or histological sample analysis if indicated.

Results

For all of the 49 cases, median survival was listed at 376 days. Thirty-day survival after surgery was 90%, with four patient deaths. 1-year survival was listed at 53%, 3-year survival at 27% and 5-year survival was listed at 19%. When the researches examined the numbers in terms of patient features, they found—not surprisingly—that patients with epithelial mesothelioma demonstrated significantly better survival times than did people with sarcomatoid or biphasic histologies.

The authors state that the cohort of patients who received induction chemotherapy prior to their EPP demonstrated a five-year survival figure of 52%—a very impressive figure for a disease that has generally resisted effective treatment. Patients who received adjuvant chemotherapy after surgery did not demonstrate any survival differences compared to those who underwent surgery alone. However, those patients who underwent a multimodal therapy consisting of surgery, chemotherapy and radiotherapy had the best overall survival figures. For these patients who survived five-years, 67% were free of tumor recurrence at five years. This number increased to 75% for those patients who underwent induction chemotherapy.

Conclusion

This study confirms two features of a number of previous studies:

1. Single modality therapy is not effective for the long-term survival of mesothelioma patients
2. An EPP is an effective surgical technique for the treatment of pleural mesothelioma, when performed as part of a multimodal approach using induction chemotherapy and radiotherapy.

The authors state that even though complications are common with EPP, these effects can often be planned for and controlled, so their potential occurrence should not automatically disqualify patients from receiving the surgery. As EPP techniques have improved, post-operative mortality has also been well-controlled. The procedure is still the best chance that patients with advanced disease or local spread have for achieving macroscopically complete resection–the removal of all visible malignant tissue–which is what many mesothelioma specialists feel is the end point of any surgery.

Labels: mesothelioma