Radical radiotherapy for stage I/II non-small cell lung cancer in patients not sufficiently fit for or declining surgery (medically inoperable)

Abstract

Background: In general, surgery is believed to offer the best prospects for cure for early stage non-small cell lung cancer (NSCLC). In spite of the intention to consider all patients with stage I-II disease for surgery, there are those who, although technically operable, either refuse surgery or are considered inoperable because of insufficient respiratory reserve, cardiovascular disease or general frailty. This group may therefore be considered "medically inoperable". Some respiratory physicians refer these patients for radical radiotherapy whilst others believe that radiotherapy has little to offer and adopt a watch policy, referring patients for palliative radiotherapy only when they become symptomatic. Although there is little evidence from randomised trials to support the use of radical radiotherapy for stage I/II NSCLC, it is the perception of most clinical oncologists (radiotherapists) that patients should receive radical, as opposed to palliative, treatment (COIN 1999).

Objectives: To determine the effectiveness and the morbidity of radical radiotherapy for medically inoperable NSCLC.

Search strategy: Randomised trials were sought by electronic searching the Cochrane Clinical Trials Register and both randomised and non-randomised trials sought by searching Medline and Excerpta Medica (Embase). Further studies were identified from references cited in those papers already identified by electronic searching.

Selection criteria: Studies of patients of any age with stage I/II NSCLC receiving radiotherapy at a dose greater than 40Gy in 20 fractions over four weeks or its radiobiological equivalent.

Data collection and analysis: Two randomised and thirty-five non-randomised studies were identified. One randomised and nine non-randomised studies did not meet the selection criteria and were not included in the review.

Main results: In the randomised trial comparing two radiotherapy schedules, two-year survival was superior following continuous hyperfractionated accelerated radiotherapy (CHART; 37%) compared to 60Gy in 30 fractions over six weeks (24%). There were 26 non-randomised retrospective studies including an estimated 2003 patients, in which overall survival results varied between 33-72% at two years, 17-55% at three years and 0-42% at five years. The proportion of deaths not due to cancer was 11-43%. Cancer-specific survival was between 54-93% at two years, 22-56% at three years and 13-39% at five years. Complete response rates were 33-61% and local failure rates between 6-70%. Distant metastases developed in approximately 25% of patients. Better response rates and survival were seen in those with smaller tumours and in those receiving higher doses though the reasons for prescribing higher doses were not clearly stated. Worse outcome was seen in those with prior weight loss or poor performance status. Assessment of treatment-related morbidity and effects on quality of life and symptom control were inconclusive because of the lack of prospective evaluation and paucity of data.

Reviewer's conclusions: There were no randomised trials that compared a policy of immediate radical radiotherapy with palliative radiotherapy given when patients develop symptoms. In the absence of such trials, radical radiotherapy appears to result in a better survival than might be expected had treatment not been given. A substantial, though variable, proportion of patients died during follow-up from causes other than cancer. The optimal radiation dose and treatment technique (particularly with respect to mediastinal irradiation) remain uncertain.