Prognostic implication of the neoadjuvant rectal score and other biomarkers of clinical outcome in Hong Kong Chinese patients with locally advanced rectal cancer undergoing neoadjuvant chemoradiotherapy.

BACKGROUND: Neoadjuvant chemoradiotherapy is a standard treatment for locally advanced rectal cancer, for which pathological complete response is typically used as a surrogate survival endpoint. Neoadjuvant rectal score is a new biomarker that has been shown to correlate with survival. The main objectives of this study were to investigate factors contributing to pathological complete response, to validate the prognostic significance of neoadjuvant rectal score, and to investigate factors associated with a lower neoadjuvant rectal score in a cohort of Hong Kong Chinese. METHODS: Data of patients with locally advanced rectal cancer who received neoadjuvant chemoradiotherapy from August 2006 to October 2018 were retrieved from hospital records and retrospectively analysed. RESULTS: Of 193 patients who had optimal response to neoadjuvant chemoradiotherapy and surgery, tumour down-staging was the only independent prognostic factor that predicted pathological complete response (P<0.0001). Neoadjuvant rectal score was associated with overall survival (hazard ratio [HR]=1.042, 95% confidence interval [CI]=1.021-1.064; P<0.0001), disease-free survival (HR=1.042, 95% CI=1.022-1.062; P<0.0001), locoregional recurrence-free survival (HR=1.070, 95% CI=1.039-1.102; P<0.0001) and distant recurrence-free survival (HR=1.034, 95% CI=1.012-1.056; P=0.002). Patients who had pathological complete response were associated with a lower neoadjuvant rectal score (P<0.0001), but pathological complete response was not associated with survival. For patients with intermediate neoadjuvant rectal scores, late recurrences beyond 72 months from diagnosis were observed. CONCLUSION: Neoadjuvant rectal score is an independent prognostic marker of survival and disease recurrence in a cohort of Hong Kong Chinese patients who received neoadjuvant chemoradiotherapy for locally advanced rectal cancer.

Adjuvant chemoradiation for gastric cancer: experience in the Chinese population.

AIMS: The role of adjuvant chemoradiation for gastric cancer after curative R0 gastrectomy was first established by the US Intergroup 0116 study. Although confirmatory studies are in progress, few data are available regarding its application to the Chinese population. We describe our radiotherapy technique and report the treatment results in Hong Kong. MATERIALS AND METHODS: This was a single centre retrospective study on 63 Chinese patients who underwent adjuvant chemoradiation for gastric adenocarcinoma between June 2000 and December 2004. The treatment protocol was based on that of the Intergroup study. Computed tomography planned anteroposterior opposing field arrangement and treatment under breath hold at deep inspiration position were adopted. RESULTS: In total, 63 patients, mean age 50 years, with gastric cancer stage IB to limited metastatic IV disease were analysed. The median follow-up time was 27.2 months. The relapse-free survival and overall survival at 3 years were 50 and 54%, respectively. The recurrence pattern was dominated by distant failure and only one patient developed isolated locoregional recurrence. Of the 10 patients who had positive microscopic surgical margins after surgery, seven had recurred and died. On multivariate analysis, margin status was the only significant prognosticator for survival. Thirty per cent of patients experienced grade 3 or above acute toxicity (24% haematological, 14% gastrointestinal) and one patient died of neutropenic sepsis. There was one case of grade 3 late toxicity. CONCLUSIONS: The outcome after adjuvant chemoradiation for gastric cancer seemed to be favourable, with manageable toxicities, in the Chinese population. Locoregional failure was uncommon. Patients with microscopic surgical margin involvement had a very high failure rate despite adjuvant chemoradiation.