K. Hyun

Erratum: Outcomes of the Multimodal Treatment of Malignant Pleural Mesiothelioma: The Role of Surgery

[This corrects the article on p. 35 in vol. 51, PMID: 29430427.].

The prognostic effect of the epidermal growth factor receptor gene mutation on recurrence dynamics of lung adenocarcinoma

OBJECTIVES The prognostic effects of epidermal growth factor receptor (EGFR) gene mutation on lung adenocarcinoma recurrence have not been well established. The relationship between EGFR gene mutation and recurrence dynamics of lung adenocarcinoma was investigated. METHODS A total of 527 patients with complete resection for adenocarcinoma were reviewed retrospectively. EGFR gene mutation was analysed by polymerase chain reaction followed by bidirectional direct sequencing in recurred patients. Patients were divided into the EGFR gene mutation group (M) or the wild-type EGFR gene group (W). Recurrence types and disease-free intervals (DFIs) of the 2 groups were compared. DFIs were calculated by the Kaplan-Meier method and compared using the log-rank test and Cox proportional hazard model. RESULTS EGFR gene sequencing was performed in 115 recurrent adenocarcinoma patients. Sixty-six patients had EGFR mutations and 49 patients had wild-type EGFR. The median DFI of the 2 groups were significantly different (M: 20.3 months, W: 15.1 months, P = 0.012). EGFR gene mutation was the only prognostic factor for DFI [hazard ratio (HR) = 0.639, 95% confidence interval (CI) = 0.428-0.954, P = 0.029]. The proportion of loco-regional recurrences and distant metastases of both groups were similar (P = 0.50). In subgroup analysis, EGFR gene mutation (HR = 0.534, 95% CI = 0.339-0.839, P = 0.007) was a significant prognostic factor for DFI of distant metastases. CONCLUSIONS Lung adenocarcinoma with EGFR gene mutations had longer DFI than those with wild-type EGFR gene, especially with regard to distant metastasis. EGFR gene mutation was a prognostic factor for lung adenocarcinoma.

A study of the learning curve for robotic oesophagectomy for oesophageal cancer

OBJECTIVES Robot-assisted minimally invasive oesophagectomy (RAMIE) enables radical, meticulous dissection of the oesophagus and lymph nodes. Our goal was to identify the effect of the learning curve for RAMIE when performing radical upper mediastinal dissection in patients with oesophageal cancer. METHODS We conducted a retrospective review of a prospectively maintained database of patients who underwent RAMIE for oesophageal cancer between May 2008 and July 2016. The gain in proficiency for each postoperative outcome measure was presented using observed-expected cumulative sum (O-E CUSUM) curves. The change points were defined at the maximal distance from the zero axis. RESULTS A total of 140 patients were included. Squamous cell carcinoma (n = 131, 93.6%) was the dominant type. Thirty-day and 90-day deaths occurred in 1 and 5 patients (0.7% and 3.6%, respectively). The change points of the risk-adjusted O-E CUSUM curves were similar to those of the unadjusted O-E CUSUM curves with the exception of those for thoracic procedure time and vocal cord palsy. The number of harvested lymph nodes increased from 25 to 45 before and after 30 cases. The vocal cord palsy rate decreased from 36% to 17% before and after 60 cases. The total operation time decreased from 496 min to 431 min; the length of the hospital stay decreased from 24 days to 14 days; and the anastomotic leakage rate decreased from 15% to 2% before and after 80 cases. CONCLUSIONS Our study demonstrated a temporal improvement in postoperative outcomes based on accumulated experience with RAMIE. The risk-adjusted O-E CUSUM curves were similar to the unadjusted O-E CUSUM curves, which represents the significant impact of the effect of a learning period on the postoperative outcomes of RAMIE in patients with oesophageal cancer.