A case of simultaneous laparoscopic surgery for double cancer comprising multiple early gastric cancer and advanced sigmoid colon cancer after revascularization

Background Traditionally, the surgery for simultaneous double cancer of the stomach and colon required a large incision to the upper and lower region of the abdomen. In this case, an artificial blood vessel was located under the skin after revascularization. Considering ischemia due to graft compression by incision retractor during laparotomy, this was difficult to do. This is a report on laparoscopic surgery for simultaneous double cancer of the stomach and colon after revascularization. Case presentation A 69-year-old man had early gastric cancer and advanced sigmoid colon cancer. He had suffered from thromboangitis obliterans and has undergone revascularization many times due to poor blood flow in his lower limbs. He had had some artificial blood vessels inserted under the skin, confirmed by blood vessel construction image by preoperative computed tomography (CT). There was a bypass vessel from the left axillary artery to the left femoral artery under the skin of the left thoracoabdominal. In addition, there were two bypass vessels from the left external iliac artery to the right femoral artery under the skin of the lower abdomen. One of the two bypasses was occluded. In the blood flow to the intestinal tract, the inferior mesenteric artery was already occluded. Peripheral blood flow in the common iliac artery depended on blood flow from the artificial blood vessel, and blood flow from the internal iliac artery to the rectum was poor. Laparoscopic Hartmann’s operation was performed for Stage II B (UICC 8th Edition) sigmoid colon cancer. Because the blood flow in the intestinal tract on the anal side was poor, we thought that anastomosis was at a high risk for leakage. Laparoscopic total gastrectomy was also performed simultaneously for two Stage I (UICC 8th edition) gastric cancers in the cardia and body. The location of the port site and stoma was carefully determined preoperatively to prevent damage and infection to the artificial blood vessels. Minimal invasive surgery was performed using laparoscopic surgery. Conclusions Laparoscopic surgery with small incisions is useful for patients with double cancer who need an approach to the upper and lower abdomen. Furthermore, laparoscopic surgery has less interference on graft in patients with artificial blood vessels under the skin by intraperitoneal approach.

Mutational concordance analysis provides supportive information for double cancer diagnosis

Background Mutation analysis using next-generation sequencing highlights the features of tumors with somatic alterations. However, the mutation profile of double cancer remains unclear. Here, we analyzed tumors derived from the same patient using whole exome sequencing (WES) to investigate the coherence of somatic mutations in double cancer. Methods First, the tumor mutational burden (TMB) was investigated using WES of 5521 tumor specimens from a Japanese pan-cancer cohort. The frequencies of mutation concordance were then compared in these cancers. Finally, we calculated the expected value of mutational concordance fitting a Poisson distribution to determine the relationship between double and metastatic cancers. Results In all, 44, 58, and 121 paired samples were diagnosed as double cancer, multifocal lesions (derived from identical tissues), and metastasis, respectively. Our analysis revealed that common somatic mutations were almost entirely absent in double cancer, whereas primary tumors and metastatic foci harbored several identical alterations. Concordance of the mutation profile in the same patient reflects the tumor origin and development, suggesting the potential for identifying double cancer based on common somatic mutations. Furthermore, according to a Poisson distribution, double cancer could be discriminated based on paired samples from the same patient. The probability of double cancer with more than 10 mutations was ≤1 part-per-billion (ppb, 10− 9). In multifocal lesions, 74% of tumor pairs accumulated ≤10 common mutations, implying a difference in tumor origin within identical tissues. Conclusions These findings indicate that counting common somatic mutations can indicate the differences in origin between tumors derived from the same patient. Our mutation coherence analysis can thus provide beneficial information for diagnosing double cancer.

Screening and treatment strategy for double cancer for esophageal cancer surgery patients.

336 Background: Esophageal cancer treatment, especially esophagectomy, is highly invasive, so treatment strategies are considered in view of existing double cancers. On the other hand, in Japan, 90% of esophageal cancers are squamous cell carcinoma, and it is known that there are a large proportion of head and neck cancers for double cancers as field cancerization. Methods: The aim of this study is to investigate the types of double cancer, simultaneous/metachronous, and the frequency and treatment policy of head and neck cancer as a particularly high coexistence rate for esophageal cancer surgery patient. The subjects were 304 patients who underwent esophagectomy performed from April 2010 to December 2017. All patients were examined with high-definition endoscopy with NBI by certificated endoscopist at the first visit as a search for simultaneous double cancer from the pharynx to the stomach. And after esophagectomy, endoscopy was also performed to check for metachronous double cancers in the remaining esophagus, gastric tube, and pharynx at least every 2 years. Results: The number of double cancer cases was found in 94 cases (30.9%), and the total number of double cancer cases was 122. Head and neck cancer(33 cases), stomach cancer(16 cases), and colon cancer(12 cases) were observed as the main course of double cancers. In double cancer cases, 47cases(50.0%) were metachronous, 35cases(37.2%) were simultaneous, and 12cases(12.8%) were both synchronous. The most common double cancer was head and neck cancer(33 cases:35.1%), and 23 cases were simultaneous, 10 cases were metachronous. As treatment strategy for head and neck cancer, endoscopic laryngo-pharyngo surgery(ELPS) were 19 cases. 10 cases(52.7%) were synchronous cancers, and 9 cases (47.3%) were metachronous cancers which were detected during follow-up after esophagectomy. Conclusions: Head and neck cancer associated with esophageal cancer surgery is the most common type of double cancer, and 1/3 of ELPS cases have been detected by follow-up endoscopy after esophagectomy, so endoscopic surveillance was also considered important.

Is preoperative screening colonoscopy useful in patients with gastric cancer?

290 Background: In patients with gastric cancer (GC), the most common double cancer is colorectal cancer (CRC). However, the meaning of screening colonoscopy has not been established. The aim of this retrospective study was to evaluate the useful of screening colonoscopy in preoperative patients with GC. Methods: This study included 689 patients who received screening colonoscopy before gastric surgery between 2012 and 2016. Multivariate analysis using logistic regression model was conducted to elucidate independent risk factors of CRC. Then, we investigated the clinicopathological factors for CRC. Results: Colorectal adenomas and CRC were observed in 315 patients (46%) and 37 patients (5.4%), respectively. The clinical T classification of the CRC were as follows; Tis: 24 patients (65%), T1: 8 patients (21%), T2: 2 patients (6%), and T3: 3 patients (8%). In multivariate analysis, male (OR 5.04, 95% C.I. 1.29-19.6, p = 0.020) was revealed as risk factor for affecting CRC. The treatments for CRC were as follows; EMR was performed in 27 patients, simultaneous resection with GC was performed in 9 patients, resection after gastrectomy was performed in 1 patient, respectively. Pathological stage of CRC was as follows; Stage 0: 24 patients, Stage I: 10 patients, and Stage IIA: 3 patients, respectively. As for the patients who underwent surgery for CRC, all of them received radical colectomy. No patient died for CRC who received colonoscopy before gastric surgery. Conclusions: Screening colonoscopy is useful for GC patients. Because most of the synchronous CRC were found early stage and curatively treated.