Joo Won Chung

Importance: The long-term safety of laparoscopic distal gastrectomy for locally advanced gastric cancer (AGC) remains uncertain given the lack of 5-year follow-up results. Objective: To compare the 5-year follow-up results in patients with clinically AGC enrolled in the Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS)-02 randomized clinical trial who underwent laparoscopic or open distal gastrectomy. Design, Setting, and Participants: The KLASS-02, a multicenter randomized clinical trial, showed that laparoscopic surgery was noninferior to open surgery for patients with locally AGC. The present study assessed the 5-year follow-up results, including 5-year overall survival (OS) and relapse-free survival (RFS) rates and long-term complications, in patients enrolled in KLASS-02. From November 21, 2011, to April 29, 2015, patients aged 20 to 80 years diagnosed preoperatively with locally AGC were enrolled. Final follow-up was on June 15, 2021. Data were analyzed June 24 to September 9, 2021. Interventions: Patients were treated with R0 resection either by laparoscopic gastrectomy or open gastrectomy as the full analysis set of the KLASS-02 trial. Main Outcomes and Measures: Five-year OS and RFS rates, recurrence patterns, and long-term surgical complications were evaluated. Results: This study enrolled a total of 1050 patients. A total of 974 patients were treated with R0 resection; 492 (50.5%) in the laparoscopic gastrectomy group (mean [SD] age, 59.8 [11.0] years; 351 men [71.3%]) and 482 (49.5%) in the open gastrectomy group (mean [SD] age, 59.4 [11.5] years; 335 men [69.5%]). In patients who underwent laparoscopic and open distal gastrectomy, the 5-year OS (88.9% vs 88.7%) and RFS (79.5% vs 81.1%) rates did not differ significantly. The most common types of recurrence were peritoneal carcinomatosis (73 of 173 [42.1%]), hematogenous metastases (36 of 173 [20.8%]), and locoregional recurrence (23 of 173 [13.2%]), with no between-group differences in types of recurrence at each cancer stage. The correlation between 3-year RFS and 5-year OS at the individual level was highest in patients with stage III gastric cancer (ρ = 0.720). The late complication rate was significantly lower in the laparoscopic than in the open surgery group (32 of 492 [6.5%] vs 53 of 482 [11.0%]). The most common type of complication in both groups was intestinal obstruction (13 of 492 [2.6%] vs 24 of 482 [5.0%]). Conclusions and Relevance: The 5-year outcomes of the KLASS-02 trial support the 3-year results, which is the noninferiority of laparoscopic surgery compared with open gastrectomy for locally AGC. The laparoscopic approach can be recommended in patients with locally AGC to achieve the benefit of low incidence of late complications. Trial Registration: ClinicalTrials.gov Identifier: NCT01456598.

Artificial intelligence has been applied to many industries, including medicine. Among the various techniques in artificial intelligence, deep learning has attained the highest popularity in medical imaging in recent years. Many articles on deep learning have been published in radiologic journals. However, radiologists may have difficulty in understanding and interpreting these studies because the study methods of deep learning differ from those of traditional radiology. This review article aims to explain the concepts and terms that are frequently used in deep learning radiology articles, facilitating general radiologists' understanding.

BACKGROUND AND AIM: Primary hepatic neuroendocrine carcinomas (PHNECs) are extremely rare, with only about 150 cases having been reported in the English-language literature. Because of the rarity of PHNECs, its clinical features and treatment outcomes are not well understood. Here, we report our experiences with PHNECs. METHODS: We identified patients diagnosed with PHNEC and analyzed their demographics, baseline laboratory data, tumor characteristics, treatment modalities and outcomes. RESULTS: A total of 218 consecutive patients were identified with pathologically confirmed neuroendocrine carcinoma. Of these, 12 patients were diagnosed with PHNECs; the median age was 66.5 years (range, 37 to 80 years), and seven patients (58.3%) were male. Two patients who each had a single hepatic mass underwent curative surgical resection. One patient who was of inoperable status at the initial diagnosis because of multiple intrahepatic metastases showed a partial response after the ninth round of systemic chemotherapy and then underwent surgical resection. The median overall survival in the 12 patients was 16.5 months (range, 0.7 to 41.7 months). Three patients who underwent surgical treatment are alive without recurrence for 15.2 months, 18.0 months, and 36.9 months, respectively. CONCLUSIONS: Primary hepatic neuroendocrine carcinoma should be considered as a possible differential diagnosis in the management of hepatic tumors. The liver can be the primary origin of neuroendocrine tumors, and if the tumors are diagnosed as primary hepatic neuroendocrine tumors, surgical resection must be considered for curative treatment.

OBJECTIVE: To investigate whether adding rifampicin to vancomycin could cure more patients with nosocomial methicillin-resistant Staphylococcus aureus pneumonia compared with vancomycin-only. DESIGN: Prospective randomized open-label study. SETTING: Medical intensive care unit in Seoul, Korea. PATIENTS: Ninety-three of 183 patients with Gram-positive nosocomial pneumonia. INTERVENTIONS: The enrolled patients with subsequently documented methicillin-resistant Staphylococcus aureus pneumonia (modified intention-to-treat population) were treated with vancomycin (1 g intravenous every 12 hrs) plus rifampicin (300 mg twice daily by mouth) (n = 41) or with vancomycin-only (n = 42). The intended treatment (at least 5 days) was completed in 30 patients in the vancomycin plus rifampicin group and 34 patients in the vancomycin-only group (per protocol population). MEASUREMENTS AND MAIN RESULTS: The primary outcome was the clinical cure rate on day 14 of treatment. The secondary outcomes were intensive care unit mortality on days 28 and 60, and microbiological eradication on day 14. The clinical cure rate in the modified intention-to-treat population was 53.7% (22 of 41) in the vancomycin plus rifampicin group, and 31.0% (13 of 42) in the vancomycin-only group (p = .047), and the respective rates in the per protocol population were 63.3% (19 of 30) and 38.2% (13 of 34) (p = .079). The respective mortality rates were nine (22.0%) of 41 and 16 (38.1%) of 42 on day 28 (p = .151), and 11 (26.8%) of 41 and 21 (50.0%) of 42 on day 60 (p = .042). The microbiological eradication rate did not differ between groups (p = .472). CONCLUSIONS: Vancomycin plus rifampicin seems to be more effective than vancomycin alone in the treatment of nosocomial methicillin-resistant Staphylococcus aureus pneumonia.