Propensity score regression analysis of oesophageal adenocarcinoma treatment with surgery alone or neoadjuvant chemotherapy

Background

Propensity score (PS) regression analysis can be used to minimize differences between cohorts in order to perform comparisons The aim of this study was to use PS analysis to examine the outcomes of oesophageal adenocarcinoma (OAC) treatment with surgery alone or neoadjuvant chemotherapy (NAC) followed by surgery (NACS), to see whether the benefits seen in a randomized trial (MRC OE02) were reproducible in a UK cancer network clinical practice.

Methods

Consecutive patients undergoing potentially curative treatment for OAC in a regional cancer network were studied. Multiple regression models, including PS analysis, were developed to account for confounding factors. Primary outcome measures were disease‐free (DFS) and overall (OS) survival.

Results

A cohort of 440 patients was included in a regression analysis controlling for confounders (176 surgery alone, 264 NACS). NACS was associated with a higher positive margin status rate compared with surgery alone (42·4 versus 26·7 per cent respectively; P < 0·001), an inferior 5‐year DFS rate (32·1 versus 56·9 per cent; P < 0·001) and a worse 5‐year OS rate (27·5 versus 47·3 per cent; P < 0·001). On regression adjustment based on propensity scores, NACS was not associated with DFS (P = 0·220) or OS (P = 0·431). The Mandard tumour regression grade (TRG) score was significantly associated with DFS (hazard ratio (HR) 0·21, 95 per cent c.i. 0·07 to 0·70) and OS (HR 0·27, 0·13 to 0·59). Five‐year DFS and OS rates related to TRG were 64 and 62 per cent respectively for 25 good responders versus 8·0 and 8·6 per cent for 127 poor responders (P < 0·001).

Conclusion

The prescription of NAC to all patients with OAC risks delay in effective treatment of patients who are relatively chemoresistant, given the variability in pathological response. Identification of patients with OAC who may derive the most benefit from NAC should be the focus.

Propensity score analysis of oesophageal cancer treatment with surgery or definitive chemoradiotherapy

BACKGROUND

The role of treatments involving surgery versus definitive chemoradiotherapy (dCRT) for oesophageal cancer remains controversial.

METHODS

Consecutive patients with oesophageal cancer were studied. Those whose treatment involved surgery alone or who received neoadjuvant chemotherapy or chemoradiotherapy were compared with those receiving dCRT. Multiple regression models, including propensity scores, were developed to assess confounding factors associated with undergoing surgery or dCRT, and the risk-adjusted association between treatment and survival.

RESULTS

From a total of 727 patients, regression adjustment to control for bias created a cohort of 521 patients available for comparison (277 in the surgery group and 244 in the dCRT group). Local and distant recurrence rates were 10·1 and 22·0 per cent respectively after surgery, compared with 26·2 and 11·9 per cent following dCRT (P < 0·001). Median survival, and 2- and 5-year survival rates after surgery were 27 months, 53·8 and 31·0 per cent respectively, compared with 28 months, 54·2 and 31·9 per cent after dCRT (P = 0·918). On multivariable analysis, disease-free survival was related to endosonographic tumour category (hazard ratio (HR) 0·76, 95 per cent confidence interval 0·10 to 6·04 for T1; HR 1·57, 0·21 to 11·58 for T2; HR 2·12, 0·29 to 15·49 for T3; HR 3·07, 0·41 to 23·16 for T4; P = 0·003, in relation to T0 as reference), lymph node metastasis count (HR 1·10, 1·04 to 1·15; P < 0·001) and total disease length (HR 0·96, 0·93 to 1·00; P = 0·041).

CONCLUSION

There was no difference in survival after oesophageal cancer treatment involving surgery or dCRT.

Review of the perceptions of general surgical staff within the Wessex region of the status of quality assurance and surgical audit

The opinion of surgical staff about the present state and effectiveness of surgical audit within a single regional health authority has been obtained by questionnaire. Seventy-five per cent of registrars/senior registrars and 72 per cent of consultants completed and returned the proforma. The majority of registrars (86 per cent) believe that it is vital or very important to collect clinical outcome information that is relevant, accurate and complete. However, more than half (56 per cent) felt that these objectives were not being met. All consultants also agreed with the statement that meaningful surgical audit and quality assurance must be based on confidential critical peer review of relevant, accurate, ongoing and complete information. None, however, believed that this objective was being met completely, while only 41 per cent felt that they were doing even 'fairly well', with the principle reason for failure being lack of time. These results support the view that most surgeons are keen to achieve meaningful audit, but at present this objective is not being satisfactorily met.