Deep learning radio-clinical signatures for predicting neoadjuvant chemotherapy response and prognosis from pretreatment CT images of locally advanced gastric cancer patients.

BACKGROUND: Early noninvasive screening of patients who would benefit from neoadjuvant chemotherapy (NCT) is essential for personalized treatment of locally advanced gastric cancer (LAGC). The aim of this study was to identify radio-clinical signatures from pretreatment oversampled computed tomography (CT) images to predict the response to NCT and prognosis of LAGC patients. METHODS: LAGC patients were retrospectively recruited from six hospitals from January 2008 to December 2021. An SE-ResNet50-based chemotherapy response prediction system was developed from pretreatment CT images preprocessed with an imaging oversampling method (i.e. DeepSMOTE). Then, the deep learning (DL) signature and clinic-based features were fed into the deep learning radio-clinical signature (DLCS). The predictive performance of the model was evaluated based on discrimination, calibration, and clinical usefulness. An additional model was built to predict overall survival (OS) and explore the survival benefit of the proposed DL signature and clinicopathological characteristics. RESULTS: A total of 1060 LAGC patients were recruited from six hospitals; the training cohort (TC) and internal validation cohort (IVC) patients were randomly selected from center I. An external validation cohort (EVC) of 265 patients from five other centers was also included. The DLCS exhibited excellent performance in predicting the response to NCT in the IVC [area under the curve (AUC), 0.86] and EVC (AUC, 0.82), with good calibration in all cohorts ( P >0.05). Moreover, the DLCS model outperformed the clinical model ( P <0.05). Additionally, we found that the DL signature could serve as an independent factor for prognosis [hazard ratio (HR), 0.828, P =0.004]. The concordance index (C-index), integrated area under the time-dependent ROC curve (iAUC), and integrated Brier score (IBS) for the OS model were 0.64, 1.24, and 0.71 in the test set. CONCLUSION: The authors proposed a DLCS model that combined imaging features with clinical risk factors to accurately predict tumor response and identify the risk of OS in LAGC patients prior to NCT, which can then be used to guide personalized treatment plans with the help of computerized tumor-level characterization.

Case report: Malignant melanoma of the lower limb with gastric metastasis.

Introduction: Malignant melanoma with gastric metastasis is extremely rare. We report a case of gastric metastasis caused by malignant melanoma of the lower limb. Case presentation: A 60-year-old woman was hospitalized for left plantar pain. The patient found a black maculopapular eruption on the left sole of her left foot, which caused pain when pressed, and the pain was aggravated by walking, so she went to our hospital for treatment. On the second day of admission, the lesion of the left foot was removed under local anesthesia, and the removed tissue was sent for pathological examination. Combined with immunohistochemistry, it was consistent with malignant melanoma. During hospitalization, the patient developed abdominal pain and asked for gastroscopy. Gastroscopy revealed two 0.5 cm × 0.6 cm spots that can be seen arising from the stomach mucosa which were slightly swollen, slightly black in the center, and without erosion, and no abnormality was found in the other parts. At the same time, a biopsy was taken under a gastroscope and pathology suggests malignant melanoma. The patient could not undergo subsequent treatment due to cost. The patient was followed up until February 2022 and was within the survival period. Conclusion: Malignant melanoma gastric metastasis is extremely rare. When a patient has a previous history of melanoma surgery, this needs to be considered when gastrointestinal symptoms are present, and regular endoscopic screening is recommended. Early surgical treatment and postoperative chemotherapy or combined targeted therapy may improve the prognosis of patients.

Case report: Laparoscopic-assisted distal gastrectomy for gastric cancer in a patient with situs inversus totalis.

Background: Situs inversus totalis (SIT) is a rare congenital disease with a series of clinical features characterized by a mirror image distribution of the viscera to the normal anatomy. Case presentation: This study aims to report a 63-year-old male SIT patient with gastric cancer with a preoperative diagnosis of stage IIB gastric cancer (cT3N0M0), who underwent a preoperative multi-disciplinary treatment (MDT) discussion and an abdominal enhancement CT for visceral evaluation to ensure a successful operation. A laparoscopic-assisted distal gastrectomy including D2 lymph node dissection and Billroth I reconstruction was successfully performed. Laparoscopic radical gastric gastrectomy and D2 lymph node dissection were performed through the opposite surgical station to the conventional one, followed by digestive tract reconstruction under small incision-assisted direct vision. There was less blood loss throughout the operation, no postoperative complications, and the patient was discharged successfully 10 days after surgery. Histopathological examination showed ulcerated high-medium differentiated adenocarcinoma stage IB (PT2N0M0). There were no complications or tumor recurrence in the patient with examination 6 months after the operation. Conclusion: Surgery in a patient with gastric cancer and SIT can be safely performed by the application of 3D laparoscopy and small incisions to assist the digestive tract reconstruction under direct vision.

Left-sided appendicitis due to anatomical variation: A case report.

Introduction: Left-sided appendicitis is a rare condition, and we report a patient with left abdominal heterotopia of the right colon complicated by acute appendicitis in the left lower quadrant. Case presentation: A 39-year-old male was admitted to hospital following left lower abdominal pain for 1 day. Imaging examination by abdominal CT showed that the appendix was not clearly seen, and a mass was found in the left lower abdomen. Because the patient's abdominal pain was severe and the current diagnosis was not clear, after soliciting the patient's consent, we performed laparoscopic exploration. This exploration revealed that the cecum and ascending colon were located in the left iliac fossa, the appendix was swollen, the length of the appendix was approximately 6 cm, the diameter of the appendix was approximately 1 cm, and there was pus moss attached to the surface. We performed a laparoscopic appendectomy; the procedure was uneventful and the patient was discharged 3 days after the procedure. Conclusion: Left-sided appendicitis is a rare condition and is therefore easy to misdiagnose. Wrong diagnosis can lead to serious complications and endanger the patient's life. Therefore, a full combination of laboratory tests and CT scan is required. If still no diagnosis can be made correctly, a laparoscopic exploration needs to be performed in a timely manner. This case teaches us that when we encounter a patient with severe left abdominal pain that cannot be definitely diagnosed, we need to be vigilant and perform timely laparoscopic exploration when necessary.

Intussusception Related to Small Intestinal Lipomas: A Case Report and Review of the Literature.

Introduction: Adult intussusception is a rare disease that is difficult to diagnose and treat and is even rarer when it is caused by a lipoma of the small intestine. We reported a case of a small intestine lipoma combined with intussusception, which can guide people in future clinical work. Case Presentation: A 51-year-old female was admitted to the hospital with "abdominal pain for 1 month." Enhanced computed tomography (CT) of the abdomen suggested a lipoma in the left lower quadrant and a proximal intussusception. After excluding surgical contraindications, laparoscopic exploration was performed on the second day of admission, which showed a small amount of ascites in the abdominal cavity, a small intestine-small intestine-type intussusception about 20 cm from the ileocecal area and about 140 cm from the ileocecal area, and a mass of about 2×4 cm that was palpable by laparoscopic intestinal forceps, which was protruded into the intestinal cavity with a soft texture and sound mobility. A 5 cm-long incision was made above the mass to dissect into the abdomen layer by layer, and the diseased intestine was dislodged outside the abdominal cavity with oval forceps. The intestine was reduced by hand and observed for half an hour after reduction, and the blood circulation and peristalsis of the intestine were observed to be still sound. The intestine was dissected at 2 cm from the upper and lower margins of the mass using linear anastomosis to operate small intestine side-to-side anastomosis. The intestine was opened concurrently and closed with a linear anastomosis, using 3-0 absorbable thread to reinforce anastomosis intermittently. The procedure went smoothly, and the patient was discharged on the 5th postoperative day. Conclusion: A small intestinal lipoma combined with small intestinal intussusception is rare in clinical practice and needs to be diagnosed by asking history detailedly, physical examination, and relevant ancillary tests such as abdominal CT. Laparoscopic-assisted small incision surgery for adult intussusception combines the advantages of laparoscopic surgery and laparotomy, operating simply and easily.

A Rare Cause of Small Bowel Obstruction: A Case Report.

Introduction: Small bowel obstruction is a common surgical emergency abdominal condition in clinical practice. Fecalith is one of the rare causative factors, especially phytobezoars. Case Report: We report the case of a 66-year-old man admitted with "abdominal pain with vomiting for 1 day." Enhanced CT of the abdomen suggested incomplete small bowel obstruction. The symptomatic treatment with fasting, fluid replacement, gastrointestinal decompression, and antibiotics was conducted after the patient was admitted to the hospital. After 2 days of treatment, the patient's abdominal pain was not significantly relieved, so a decision was made to perform laparoscopic examination surgery. During surgery, a columnar foreign body was found embedded in the lumen of the small intestine about 10 cm away from the ileocecal region. Combined with the patient's preoperative history of consuming a large number of persimmons, the primary diagnosis of small intestinal fecalith obstruction was considered. We performed an enterotomy to remove the foreign body, and the procedure was uneventful. On postoperative day 7, the patient was successfully discharged. Conclusion: When we encounter a patient with intestinal obstruction without a history of surgery in our clinical work, we should take a careful history, especially about the consumption of foods that can cause phytoliths. When a patient has consumed a large amount of food that can cause phytobezoars before the abdominal pain, we should diagnostically consider it as phytobezoars intestinal obstruction, which helps to reduce the incidence of misdiagnosis and allows the patient to receive treatment timely and effectively.

Abdominal Cocoon With Intestinal Perforation: A Case Report.

Introduction: Abdominal cocoon is a very rare abdominal disease. Abdominal cocoon mainly leads to intestinal obstruction, and abdominal cocoon with gastrointestinal perforation is rare. Case Presentation: We report a 63-year-old man who was admitted to our hospital with "persistent lower abdominal pain for one day". Abdominal CT examination revealed a small amount of free gas in the abdominal cavity, ascites, and gastrointestinal perforation. An emergency operation was performed. During the operation, the end of the right lower abdominal ileum was found to be conglutinated and twisted into a mass, a local intestinal dilatation, and obstruction, local intestinal wall was black and gangrene, and fecal effusion flowed out. The adhesions were carefully separated, and the necrotic small intestine was removed. The operation process went smoothly, and the patient recovered well after the operation. Conclusion: The cases of intestinal perforation caused by the abdominal cocoon are very rare. In clinical work, when we encounter patients with gastrointestinal perforation, we need to carefully ask the history. When the patients had no digestive system diseases in the past, we need to consider the possibility of the abdominal cocoon with perforation.

A case of iatrogenic intussusception in adults: a rare case report.

BACKGROUND: Intussusception has a low incidence rate in adults. Many cases in adults are caused by tumors. Intussusception results from conditions other than tumors are uncommon. This is the first case report about intussusception that occurred after removing a long intestinal tube (LT). CASE PRESENTATION: A 69-year-old female complained of "recurrent abdominal pain with reduced flatus passage and frequency of bowel movement for 10 days" was admitted to the hospital. Plain abdominal radiography and abdominal CT upon admission showed intestinal obstruction. The patient's abdominal pain was not relieved after symptomatic treatments, which involved fluid and electrolyte replacement, LT placement, spasmolytic agents, and analgesics. Hence, surgical exploration was carried out. The patient had a good recovery postoperatively. No abdominal pain or bloating developed after food intake. The patient passed flatus and had bowel movements later. On postoperative day 9, the LT was removed. On the 10th day, the patient suddenly developed abdominal distension and acute abdominal pain. Emergency abdominal CT showed small bowel intussusception. Surgical exploration was then performed. Severe small bowel dilatation located at 1.5 m from the ligament of Treitz was found during the procedure. Intussusception at the site was observed. No color change of the intestinal wall was detected, suggesting that no necrosis was present. So, a manual reduction was done. The patient was discharged on postoperative day 6. CONCLUSIONS: This case serves as a warning that the simple action of pulling out the LT might also cause serious complications, which should be given more attention.