Extrapleural Pneumonectomy - Pleurectomy, Mesothelioma
Radical 'Curative' Surgery: Extrapleural Pneumonectomy
Radical EPP classically has been described for pure epithelial tumor, stage I that is technically resectable and encapsulated by the parietal pleura. Due to sampling error, it is impossible to clarify with 100% certainty whether the tumor is a pure epithelial type or mixed tumor on the basis of the preoperative or intraoperative biopsy.
The centers that are able to attract large numbers of mesothelioma patients due to ongoing prospective trials may be relaxing the socalled 'classic indications' based on stage, age, and histology. Surgeons at these institutions are chiefly concerned with the patients' functional ability to tolerate the operation and the ability to accomplish maximal tumor debulking. If, indeed, higher-stage patients can undergo the operation with risks equal to pleurectomy-decortication, enthusiasm for its general incorporation in more aggressive adjunctive trials would be justified.
There are few patients who actually qualify for exploration outside the research setting. In Butchart's review, 29 of 46 or 63% of patients were eligible for EPP.40 The only other series that reveals this percentage is DaValle's, where 33 of 56 patients over a 27-year period had EPP (59%).96a Sugarbaker has recently reported 50% of the patients seen at his institution are not eligible for EPP and adjuvant therapy.
Unfortunately, these series really do not define why one patient may have a pleurectomy while another would have EPP, and it is obvious, however, that some institutions have simply never adopted the operation as feasible for treatment of the disease.
Probably the most enlightening study on eligibility was the Lung Cancer Study Group (LCSG) malignant mesothelioma pilot study from 1985 to 1988.226 To be eligible for entry into the study the patient was required to have disease limited to the hemithorax by radiographic evaluation, a residual FEV1 after resection of at least 1L/s and no significant cardiovascular illness - clearly more lenient criteria than those which limited eligibility due to age, histologic type, or presumed stage. Even with these 'relaxed" criteria, only 20 of the 83 evaluated patients were resected with an EPP. The reasons that EPP could not be performed were chiefly extent of disease not allowing complete gross resection (54%), inadequate respiratory reserve (33%), stage IV disease (11%), and concurrent medical illness (10%).
Due to its magnitude, EPP has significantly greater morbidity than pleurectomy. The major complication rate ranges from 20 to 40%, and arrhythmia requiring medical management is the most common complication.
In Sugarbaker's most recent report, major morbidity occurred in 24% of the patients having EPP and minor morbidity in 41%.257a The rate for bronchopleural fistula is greater with right-sided EPPs with an overall fistula rate of 3 to 20%. The bronchopleural fistula can be handled, for the most part, with open thoracostomy drainage with or without muscle flap interposition.
The mortality rates following EPP were unacceptably high in the 1970s with a 31% reported by Butchart.40 Since then, however, there has been a steady decline in the operative mortality for the operation to consistent rates less than 10% in series of 20 or more patients. Mortality occurs chiefly in older patients from respiratory failure, myocardial infarction, or pulmonary embolus. Rusch229 reported a perioperative mortality of 6% (3 of 50) after EPP and Sugarbaker reports a perioperative mortality of 3.8% from myocardial infarction and presumed pulmonary emboli.257a
Rusch226 described sites of recurrence after EPP to be distant areas, compared with biopsy only or pleurectomy-decortication, and the local control was superior to that of the other modalities. Pass and colleagues195c also found a higher proportion of first sites of local recurrence seen in the pleurectomy population, compared with the patients having EPP. In Sugarbaker's series of patients, Baldini has reported that the sites of first recurrence were local in 35% of patients, abdominal in 26%, the contralateral thorax in 17%, and other distant sites in 8%.19a Long-term survival rates after EPP remain disappointing with the median survivals ranging from 9.3 to 17 months for the majority series