The risk of weekend biopsy: Impact of specimen source and fixation status on HER2 assessment in the treatment of advanced gastric cancer (The HER_WEEKEND study).

Accurate evaluation of human epidermal growth factor receptor type 2 (HER2) expression is crucial for determining chemotherapy regimens in gastric cancer. However, formalin fixation status has been identified as an important factor affecting HER2 assessment reliability. This retrospective cohort study aimed to investigate the correlation between sample collection day (weekday vs. weekend) and source (biopsy vs. surgical specimens) in assessing HER2 expression in patients with unresectable advanced/recurrent gastric cancer. Data were collected from gastric cancer patients who received chemotherapy at a single public hospital in Japan from 2008 to 2021. The analysis included 177 patients (109 men, 68 women) with a median age of 68.0 (21-88) years, and the primary outcome was the HER2 positivity rate. The overall HER2 positivity rate was 18.1%, with higher rates on weekdays (20.0%) compared to weekends (12.8%). Biopsies had higher positivity rates on weekdays (23.9%) but lower rates on weekends (11.1%) than surgical specimens. Significant differences were observed in formalin fixation times between weekdays and weekends for both biopsies and surgical samples. The study findings suggest that longer formalin fixation times on weekends may lead to underestimating HER2 expression, particularly in biopsies. Therefore, it is crucial to be cautious of excessive formalin fixation when collecting samples, especially during weekend biopsies.

The incidence of cardiovascular thrombotic complications after laparoscopic resection in colorectal cancer in Japanese hospitals: A large-scale clinical study.

Aim: The aim of this retrospective study was to investigate the incidence of cardiovascular thrombotic complications after laparoscopic resection in colorectal cancer. Methods: This study involved 2017 patients with stages 0-III colorectal cancer who underwent laparoscopic surgery at 17 Japanese hospitals between January 2010 and December 2013. We assessed the incidence of postoperative cardiovascular thrombotic and haemorrhagic complications. Results: Laparoscopic surgeries were performed in 1152 men and 865 women with 1405 colon and 612 rectal cancers, respectively. Overall, 3%, 38%, 17%, 8%, and 9% of patients had comorbidities of heart failure, high blood pressure, diabetes, history of stroke, and vascular disease, respectively. Antithrombotic agents were being consumed by 17% of patients. The types (and perioperative rest periods) of the antithrombotic agents were aspirin in 58% (18.6 days), clopidogrel in 19% (21.1 days), cilostazol in 13% (13.3 days), and warfarin potassium in 21% (14.6 days) of cases with antithrombotic agents. Surgical time and blood loss in the total cohort were 234 minutes and 56 mL. Four cases (0.2%) had cardiovascular thrombotic complications, including one severe cardiac infarction and one stroke with major sequelae (CHADS2 scores were 2 points in both cases). Hemorrhagic complications occurred in 19 cases (0.9%). In particular, the incidence of the major gastroduodenal haemorrhagic ulcer was higher in cases with antithrombotic agents than without them (0.05% vs 0%, P = .02). Conclusion: The incidence of cardiovascular thrombotic complications was rare, although severe cardiac infarction and stroke could occur even after minimally invasive surgery in colorectal cancer.

Morphological observation of process of mouse temporomandibular joint formation.

The aim of this study was to clarify the developmental mechanism of the temporomandibular joint (TMJ) cavity, using the relationship between Meckel's cartilage and the mandible to morphologically observe the process of TMJ formation in mouse fetuses. We investigated the involvement of apoptosis in the development of the mouse TMJ cavity. We attempted to 3-dimensionally clarify the developmental process of the mandible and Meckel's cartilage by observing the developmental process optically and reconstructing 3-dimensional images to observe 3-dimensional locations of the mandible and Meckel's cartilage. Formation of the upper joint cavity began on embryonal day 16, and a complete joint cavity was formed on embryonal day 18. Formation of the lower joint cavity began on embryonal day 18, and formation was almost completed on embryonal day 19. Meckel's cartilage adjacent to the mandible decreased with development of the mandible but was vestigial on embryonal day 19. The posterior region of Meckel's cartilage developed toward the posterior direction, and it was 3-dimensionally confirmed that the mandible and Meckel's cartilage were separated. Histological observation by the TUNEL method revealed the presence of solitary and diffuse apoptotic cells not only in the joint cavity, but also around the condyle.