In colorectal cancer, whereas mucinous adenocarcinoma (MAC) has several poor clinical prognostic factors compared to adenocarcinoma (AC), the prognosis of MAC remains controversial. We evaluated the prognosis of MAC without distant metastasis and the effects of adjuvant chemotherapy using health insurance registry data managed by South Korea. Patients with colorectal cancer between January 2014 and December 2016 were included (AC, 22,050 [96.8%]; MAC, 729 [3.2%]). We observed no difference in overall survival (OS) between AC and MAC in stages I and II. However, MAC showed a worse OS than AC in stage III disease, especially in patients administered chemotherapy (p < 0.001). These findings persisted after propensity score matching of clinical characteristics between AC and MAC. In addition, transcriptome analysis of The Cancer Genome Atlas (TCGA) data showed increased chemoresistance-associated pathways in MAC compared to AC. In consensus molecular subtypes (CMS) classification, unlike in AC, CMSs 1, 3, and 4 comprised most of MAC and the proportions of CMSs 3 and 4 increased with stage progression. These results suggest clues to overcome resistance to chemotherapy and develop targeted treatments in MAC.

Purpose: To delineate the learning curve (LC) for laparoscopic appendectomy (LA) performed by residents according to seniority in training.Methods: Between October 2015 and November 2016, 150 patients underwent LA by three residents (in their first, second, and third year of training) under supervision. The patients were non-randomly assigned to each resident. The data were reviewed and analyzed retrospectively from prospectively collected database. The perioperative outcomes were compared between the three residents including operation time, complication, conversion, and so on. The LCs were evaluated by the moving average method and cumulative sum control chart (CUSUM) for operation time and surgical completion.Results: Baseline characteristics and perioperative outcomes were similar except for age and location of the appendix among the three groups. Operation time was not different among the three residents (43.9, 45.3, and 48.4 min for A, B, and C, respectively). The moving average method for operation time showed a decreasing tendency for all residents. CUSUM for operation time showed that the peak points occurred at the 24th, 18th, and 31st cases for resident A, B, and C, respectively. In terms of surgical failure, residents A, B, and C reached steady states after the 35th, 11th, and 16th cases, respectively. Perforation of the appendix base was the only risk factor for surgical failure.Conclusion: The LC for LA by residents was 11-35 cases according to multidimensional statistical analyses. The accumulation of surgical experience of residents might affect the LC, especially for surgical completion rather than for operation time.

This operative report documents the details of a surgery. Standardization of the medical terminology for the operative report written in free text is significant for performing medical research and establishing insurance systems by accurately sharing information on treatment. However, standardization of operative reports is a labor-intensive task that has a risk of induced errors. We have proposed a concatenation of bidirectional encoder representations from transformers (ConBERT) model for predicting the International Classification of Disease-9 code using the operative report and diagnosis recorded in free text to standardize the operative report automatically. We compared the pre-trained models of BERT and character BERT and created a new model by concatenating the combinations of each model. The proposed ConBERT model showed a micro AP score of 0.7672, F1 score of 0.7415, and AUC of 0.9842. In addition, we developed a web-based application to demonstrate the performance of our model and make it publicly accessible.