Extra-pleural pneumonectomy versus no extra-pleural pneumonectomy for patients with malignant pleural mesothelioma: clinical outcomes of the Mesothelioma and Radical Surgery (MARS) randomised feasibility study

BACKGROUND

The effects of extra-pleural pneumonectomy (EPP) on survival and quality of life in patients with malignant pleural mesothelioma have, to our knowledge, not been assessed in a randomised trial. We aimed to assess the clinical outcomes of patients who were randomly assigned to EPP or no EPP in the context of trimodal therapy in the Mesothelioma and Radical Surgery (MARS) feasibility study.

METHODS

MARS was a multicentre randomised controlled trial in 12 UK hospitals. Patients aged 18 years or older who had pathologically confirmed mesothelioma and were deemed fit enough to undergo trimodal therapy were included. In a prerandomisation registration phase, all patients underwent induction platinum-based chemotherapy followed by clinical review. After further consent, patients were randomly assigned (1:1) to EPP followed by postoperative hemithorax irradiation or to no EPP. Randomisation was done centrally with computer-generated permuted blocks stratified by surgical centre. The main endpoints were feasibility of randomly assigning 50 patients in 1 year (results detailed in another report), proportion randomised who received treatment, proportion eligible (registered) who proceeded to randomisation, perioperative mortality, and quality of life. Patients and investigators were not masked to treatment allocation. This is the principal report of the MARS study; all patients have been recruited. Analyses were by intention to treat. This trial is registered, number ISRCTN95583524.

FINDINGS

Between Oct 1, 2005, and Nov 3, 2008, 112 patients were registered and 50 were subsequently randomly assigned: 24 to EPP and 26 to no EPP. The main reasons for not proceeding to randomisation were disease progression (33 patients), inoperability (five patients), and patient choice (19 patients). EPP was completed satisfactorily in 16 of 24 patients assigned to EPP; in five patients EPP was not started and in three patients it was abandoned. Two patients in the EPP group died within 30 days and a further patient died without leaving hospital. One patient in the no EPP group died perioperatively after receiving EPP off trial in a non-MARS centre. The hazard ratio [HR] for overall survival between the EPP and no EPP groups was 1·90 (95% CI 0·92-3·93; exact p=0·082), and after adjustment for sex, histological subtype, stage, and age at randomisation the HR was 2·75 (1·21-6·26; p=0·016). Median survival was 14·4 months (5·3-18·7) for the EPP group and 19·5 months (13·4 to time not yet reached) for the no EPP group. Of the 49 randomly assigned patients who consented to quality of life assessment (EPP n=23; no EPP n=26), 12 patients in the EPP group and 19 in the no EPP group completed the quality of life questionnaires. Although median quality of life scores were lower in the EPP group than the no EPP group, no significant differences between groups were reported in the quality of life analyses. There were ten serious adverse events reported in the EPP group and two in the no EPP group.

INTERPRETATION

In view of the high morbidity associated with EPP in this trial and in other non-randomised studies a larger study is not feasible. These data, although limited, suggest that radical surgery in the form of EPP within trimodal therapy offers no benefit and possibly harms patients.

FUNDING

Cancer Research UK (CRUK/04/003), the June Hancock Mesothelioma Research Fund, and Guy's and St Thomas' NHS Foundation Trust.

Constrictive Pericarditis After Left Extrapleural Pneumonectomy and Radiotherapy for Malignant Mesothelioma

We report the devastating complication of constrictive pericarditis after multimodality therapy including left extrapleural pneumonectomy for malignant pleural mesothelioma. The patient presented with progressive dyspnea, ascites, and peripheral edema 6 months after receiving adjuvant radiotherapy. A diagnosis of constrictive pericarditis was made late in the clinical course after exhaustive investigation to exclude primary disease recurrence. Pericardial decortication was subsequently undertaken 12 months after the initial surgery, but the patient died of multi-organ failure. Our experience, combined with a review of the available literature, leads us to advise a low level of suspicion and early operation to relieve cardiac constriction. Furthermore, these complications emphasize the importance of trials such as the Mesothelioma and Radical Surgery (MARS) study.

Prolonged survival in a patient with recurrent pulmonary metastases secondary to mucinous cystadenocarcinoma of the appendix with pseudomyxomatous peritonei

We report a 65-year-old man presenting with recurrent pulmonary metastases 20 years after an appendectomy for mucinous cystadenocarcinoma with pseudomyxomatous peritonei. He underwent bilateral staged metastatectomies for metastases 7 years after the diagnosis and further metastasectomy after a recent recurrence. This is a rare case of recurrent pulmonary metastatic mucinous cystadenocarcinoma, and despite poor prognosis and nondefinitive initial treatment, this patient remains alive and well 20 years later.

How best to manage the space after pneumonectomy? Theory and experience but no evidence

OBJECTIVE

We set out to find a policy for the management of the pneumonectomy space which would minimise risk and be acceptable to all the surgeons. We believe this will reduce opportunities for error, be welcomed by nursing staff, and improve adherence to protocols.

METHODS

We sought evidence in the scientific and educational literature. Finding no sure guidance, we audited our own experience of two policies, with the emphasis on minimising risk.

RESULTS

There was no evidence from randomised trials. There was no cohesive advice in the text books. Our data indicated that it was improbable that randomised controlled trial (RCT) would have the power to find the evidence. Unable to establish the best strategy, we chose what appeared to be the lowest risk management policy.

CONCLUSIONS

It is instructive that such a fundamental question should be unanswered. We have adopted a low risk and well established strategy--an unclamped underwater seal drain--but have no evidence base other than clinical experience. This is illustrative of much of what we do in clinical surgical practice. Avoiding major risk is often more important than proving small differences in benefit.

Combined lung resection and transdiaphragmatic adrenalectomy in patients with non-small cell lung cancer and homolateral solitary adrenal metastasis

Surgery may offer a long-term survival benefit to a small proportion of patients with operable non-small cell lung cancer (NSCLC) and solitary adrenal metastasis. Several approaches to lung resection with a separate open or laparoscopic adrenalectomy have been advocated. We describe a technique that allows a single incision, single operation through a transdiaphragmatic approach to the ipsilateral adrenal gland following a standard lung resection through a postero-lateral thoracotomy. By using this approach, along with the harmonic scalpel to aid adrenal dissection, both lobectomy and adrenalectomy can be carried out safely and effectively with minimal perioperative and postoperative morbidity.

A prospective randomized controlled trial of suction versus non-suction to the under-water seal drains following lung resection

OBJECTIVE

Practice varies as to whether or not suction is applied to under-water seal drains following lung surgery. We tested the null hypothesis that there is no difference with respect to air leak duration.

METHODS

Patients undergoing thoracotomy or video assisted thoracoscopic surgery for lobectomy or wedge resection had either low-pressure suction or no suction applied to their underwater seal bottles postoperatively. Patients were allocated using minimization, a method of unbiased allocation ensuring balance between the arms of a trial with respect to known or suspected confounding factors. The trial was powered for duration of air leak. If an air leak persisted on the 7th post-operative day, the surgeon determined further management. Kaplan-Meier survival analysis of air leak duration and a log rank test were performed on an intention-to-treat basis, with observations censored at 144h (6 complete days).

RESULTS

Of the 254 patients that entered the trial, data were available for analysis for 239 (123 no-suction and 116 suction). There was no significant difference in the cumulative persistence of air leaks between the two groups (P=0.62) and inspection of the Kaplan-Meier curves suggests that any difference is negligible.

CONCLUSIONS

Applying suction to the underwater seal drains following lung surgery makes no difference in terms of air leak duration. In the light of this finding we have adopted a uniform policy of no suction being applied to the underwater seal, from the time of surgery, unless a specific clinical judgment is made to use it. The anticipated gains are that this will reduce work and cost and aid mobilization.