Fatal bowel perforation caused by ingestion of high-powered magnets in a 6-year-old boy.

Foreign body ingestion in children is a frequent cause for medical consultation. Although most foreign bodies are spontaneously eliminated from the gastrointestinal tract, life-threatening complications such as gastrointestinal obstruction or perforation can occur. We report the case of a 6-year-old boy who died 2 days after the onset of nausea and abdominal pain, with no foreign body ingestion witnessed or reported in the previous days. Autopsy showed a diffuse peritonitis and a perforation of the transverse colon caused by three high-powered magnets stacked together, and attached to the outer stomach wall via a fourth magnet located in the stomach. The cause of death was peritonitis due to bowel perforation by ingested magnets, which were shown to have come from a toy belonging to the child. Ingestion of multiple high-powered magnets carries a high risk of gastrointestinal complications and can exceptionally have a fatal outcome, especially as it often goes unreported and causes non-specific gastrointestinal symptoms that can delay diagnosis and management. This case highlights the need to raise public awareness of the potential risks of ingesting such magnets and to strengthen safety standards to protect children from this serious health hazard.

Optimal surgical approach for mid-transverse colon cancer: a systematic review and meta-analysis.

BACKGROUND AND AIM: The incidence of cancer colon has increased dramatically. In addition, the database lacks a review to analyze the outcomes of surgeries for mid-transverse colon cancer with several recent controversial studies. We aimed to compare the outcomes of extended hemicolectomy versus transverse colectomy for mid-transverse colon cancer. METHOD: PubMed, Scopes, Web of Science and Cochrane Library were searched for eligible studies from inception to 1 December 2022 and a systematic review and meta-analysis were done to detect. RESULTS: According to eligibility criteria, 8 studies (2237 patients) were included in our study. The pooled results of the included studies showed no difference in the 5-year OS, 3-year DFS and 5-year DFS between the two types of surgery (5-year OS, RR = 1.15, 95% CI 0.94-1.39, P = 0.17), (3-year OS, RR = 0.96, 95% CI 0.88-1.06, P = 0.42) and (5-year DFS, RR = 1.21, 95% CI 0.91-1.62, P = 0.20). In addition to that, the recurrence rate and the incidence of complications were similar in the two groups (Recurrence rate, RR = 1.08, 95% CI 0.62-1.89, P = 0.79) and (Complications, RR = 1.07, 95% CI 0.74-1.54, P = 0.72). However, the number of LN harvest and the time of the operation were more in case of extended hemicolectomy. CONCLUSION: Despite harvesting less LN, transverse colectomy has similar oncological outcomes to extended hemicolectomy for mid-transverse colon cancer. In addition to that, there was no significant difference in the incidence of complications between the two surgeries.

Novel approach toward minimally invasive surgery for mid-transverse colon cancer: 'moving the left colon' technique.

AIM: During surgery for mid-transverse colon cancer (MTC), surgeons often face the dilemma of whether to mobilize the hepatic or splenic flexure. There is no established optimal minimally invasive surgical procedure for MTC. METHODS: We present our novel minimally invasive surgical technique, called the 'moving the left colon' technique for MTC, along with a video demonstration. The procedure involves four main steps: (i) mobilization of the splenic flexure using a medial-to-lateral approach, (ii) dissection of lymph nodes around the middle colic artery from the left side of the superior mesenteric artery approach, (iii) separation of the pancreas and transverse mesocolon and (iv) 'moving the left colon' and performing an intracorporeal anastomosis. By mobilizing the splenic flexure, anatomical landmarks are revealed, which enables safer dissection. Combining this technique with intracorporeal anastomosis allows for a safe and easy anastomosis. RESULTS: Between April 2021 and January 2023, a single-skilled colorectal surgeon performed laparoscopic transverse colectomies using our new approach on three consecutive patients with MTC. The patients had a median age of 75 years (range 46-89 years). The median operative time was 194 min (range 193-228 min) and blood loss was 8 mL (range 0-20 mL). None of the patients experienced any perioperative complications and the median postoperative hospital stay was 6 days. CONCLUSION: We introduced a novel approach for laparoscopic surgery for MTC. This technique can be performed safely and may help standardize minimally invasive surgery for MTC.

Laparoscopic D3 oncological resection in splenic flexure cancer: Technical details and its impact on long-term survival.

AIM: The applicability of laparoscopic D3 oncological resection for splenic flexure cancer (SFC) surgery has not been fully explored due to technical difficulties and variations in surgical procedure. The aim of this work is to describe the feasibility of performing laparoscopic D3 resection in SFC and its impact on long-term survival. METHOD: A retrospective study on 47 out of 52 consecutive patients who underwent elective laparoscopic colectomy for SFC from December 2006 until December 2019 at Korea University Anam Hospital was performed. Data on patients' demographic and clinical features, surgical procedures, intraoperative and postoperative complications, pathological features and follow-up were collected. Categorical data are expressed as frequencies (n) and percentages (%). Continuous data are expressed as mean ± standard deviation and median (range). The Kaplan-Meier test was used to determine the overall survival (OS), progression-free survival (PFS) and disease-free survival (DFS). RESULTS: The median age of patients was 67.0 years (range 27-87 years) and 72.3% were men. Ten (21.3%) patients presented with an obstructing tumour and underwent an elective laparoscopic colectomy, while 68.1% of patients presented with Stage II and III disease. The conversion rate was 4.3% and the morbidity rate was 31.9%. There was one postoperative death secondary to splenic infarction and anastomotic leak leading to multi-organ failure. Four deaths occurred due to disease progression during a median follow-up of 63.8 months. The rate of recurrence was 20%, the 5-year OS was 89.6% and the 5-year PFS was 72.9%. After R0 resection, the 5-year OS was 91.5% and the 5-year DFS was 74.5%. CONCLUSION: Laparoscopic D3 colectomy for SFC is feasible, with an acceptable morbidity and long-term oncological outcome when performed by highly skilled laparoscopic colorectal surgeons with knowledge of the complex anatomy around the splenic flexure. Further randomized trials should be performed to determine the advantage of laparoscopic D3 colectomy over conventional colectomy for SFC.

Usefulness of the endoscopic surgical skill qualification system for laparoscopic colectomy for transverse colon cancer: a Japanese multicenter analysis.

PURPOSE: Laparoscopic colectomy for transverse colon cancer (TCC) can be technically demanding due to the anatomical complexity of the region. In Japan, the Endoscopic Surgical Skill Qualification System (ESSQS) was established to improve the skill of laparoscopic surgeons and further develop surgical teams. We examined the safety and feasibility of laparoscopic colectomy for TCC and evaluated the effects of the Japanese ESSQS in facilitating this approach. METHODS: We retrospectively reviewed 136 patients who underwent laparoscopic colectomy for TCC between April 2016 and December 2021. Patients were divided into an ESSQS-qualified surgeon group (surgery performed by an ESSQS-qualified surgeon, n = 52) and a non ESSQS-qualified surgeon (surgery performed by a non ESSQS-unqualified surgeon, n = 84). Clinicopathological and surgical features were compared between groups. RESULTS: Postoperative complications occurred in 37 patients (27.2%). The proportion of patients who developed postoperative complications was lower in the ESSQS-qualified surgeon group (8.0%) than that in the non ESSQS-qualified surgeon group (34.5%; p < 0.017). Multivariate analysis revealed "Operation by ESSQS-qualified surgeon surgeon" (odds ratio (OR) 0.360, 95% confidence interval (CI) 0.140-0.924; p = 0.033), blood loss (OR 4.146, 95% CI 1.688-10.184; p = 0.002), and clinical N status (OR 4.563, 95% CI 1.814-11.474; p = 0.001) as factors independently associated with postoperative complications. CONCLUSION: The present multicenter study confirmed the feasibility and safety of laparoscopic colectomy for TCC and revealed that ESSQS-qualified surgeon achieved better surgical outcomes.

Analysis of surgical outcomes of laparoscopic versus open surgery for locally advanced mid-transverse colon cancer.

PURPOSE: This study compared the surgical outcomes between laparoscopic colectomy (LC) and open colectomy (OC) for mid-transverse colon cancer (MTC). METHODS: This multicenter retrospective study compared the short- and long-term surgical outcomes for patients with advanced MTC (T3 and T4 with or without nodal involvement) who underwent LC or OC between January 2008 and December 2019 using a propensity score-matched analysis. RESULTS: A total of 177 patients with advanced MTC were enrolled. After matching, 58 cases for the OC and LC groups were selected. No significant differences in age, sex, tumor progression, or procedure type (extended resection or segmental resection) existed between groups. The LC group had significantly less blood loss (20 mL vs. 50 mL, p=0.048) and a shorter postoperative hospital stay (8 days vs. 12 days, p<0.001) than the OC group. Postoperative complications (Clavien-Dindo grade ≥ 2) occurred in 27.6% and 25.9% of the OC and LC groups respectively (p=1). Three patients (5.2%) and one patient (1.7%) of the OC and LC groups respectively developed anastomotic leakage (p=0.62). Re-operation was required in five patients (8.6%) in the OC group and one patient (1.7%) in the LC group (p=0.21). No surgery-related deaths occurred in either group. The 3-year overall survival rates (stage II: LC 100% vs. OC 92.8%, p=0.15; stage III: 88.9% vs. 84.3%, p=0.88, respectively) were similar between the two groups. CONCLUSION: LC is a minimally invasive technique with lesser blood loss, shorter postoperative hospital stays, and oncologic equivalence to OC. Hence, LC is useful for MTC treatment. TRIAL REGISTRATION: UMIN000042676.

[A Case of Right Hemicolectomy for Inflammatory Myofibroblastic Tumor Arising in the Right Transverse Colon].

The patient was a 21-year-old male. He presented with right lower abdominal pain and showed tenderness in the same area. An abdominal contrast-enhanced CT examination revealed a 45 mm tumor that continuously stained in the right transverse colon. The patient presented with tenderness and rebound tenderness. Due to a suspected submucosal tumor, laparotomy was performed and an elastic hard tumor of 5 cm in size was found on the serous membrane side of the right transverse colon. As malignancy could not be ruled out, a right hemicolectomy with lymph node dissection was performed. The pathological diagnosis was an inflammatory myofibroblastic tumor(IMT), characterized by the proliferation of spindle- shaped spindle-shaped fibroblast-like cells with inflammatory cell infiltration. As of 9 years post-surgery, there has been no recurrence. However, long-term surveillance is necessary.

[A Case of Response to Pembrolizmab in Unresectable MSI-High Transverse Colon Cancer].

A 80s man was diagnosed circulated type 2 colon cancer at the transverse colon, and pathological findings was adenocarcinoma( por1). Genomic findings were microsatellite instability-high(MSI-H), all RAS wild type and BRAFV600E mutated. Contrast-enhanced CT showed an enlarged lymph nodes(#221, #222, #223, #214)along the middle colic and superior mesenteric artery. Clinical diagnosis was a locally advanced unresectable transverse colon cancer, cT4aN3M1a(LYM), cStage Ⅳa. Drug therapy with pembrolizumab was prescribed. Six months later, contrast-enhanced CT and PET demonstrated remarkable shrinkage of the primary tumor and lymph nodes except 2 peri-colic enlarged lymph nodes. Primary lesion turned almost undetectable, however the biopsy demonstrated residual tumor. Two months later, CT showed that the residual lymph nodes had also disappeared.

[A Case of Submucosal Invasion(SM2)Gastric Cancer with Peritoneal Dissemination Three Years after Surgery].

The patient is a 90-year-old man. Three years and 3 months after laparoscopic distal gastrectomy for early gastric cancer, pT1b(SM2)pN1M0, Stage Ⅰ, the patient visited our hospital with abdominal pain, and a large amount of ascites and stenosis of transverse colon were pointed out. He underwent a right hemicolectomy under laparotomy. Histopathologically, it was diagnosed as peritoneal recurrence of previous gastric cancer. Postoperatively, he died of aspiration pneumonia. As for the cause of death after surgery of early gastric cancer, there are many causes of death from other diseases and few from primary malignancy. Furthermore, recurrence of peritoneal dissemination is extremely rare and considered to be a valuable case.

[A Case of Pathologic Complete Response Achieved with Preoperative Pembrolizumab Therapy for Transverse Colon Cancer].

A 77-year-old female patient presented with a medical history of 4 cancerous lesions, each with a surgical history. She was referred to our hospital due to anemia. Upon examination, she was diagnosed with transverse colon cancer. Duodenal invasion was suspected, which made performing R0 surgery difficult; therefore, the NAC approach was chosen. Three courses of CAPOX were administered, resulting in tumor obstruction, leading to the formation of an ileum stoma. MSI testing revealed MSI-H, and pembrolizumab treatment was initiated. CT scans showed tumor shrinkage, and PET scans indicated no accumulation, resulting in a cCR. Colon resection including the lesion suspected of stenosis was performed with a strong desire for stoma closure and the determination of potential curative resection. Additionally, a partial resection of the duodenum was performed. Pathological examination did not reveal any evident tumor cells, leading to the determination for a pCR. The patient has been under postoperative surveillance for 1 year without any recurrence.

[A Case of Pancreatic Tail Cancer Causing Gastrointestinal Hemorrhage Due to Transverse Colon Invasion].

An 81-year-old woman was admitted to our hospital due to frequent bleeding and hemorrhagic shock. Blood tests revealed anemia and contrast-enhanced abdominal CT revealed a pancreatic tail tumor with a diameter of 60 mm. The boundary between pancreatic tumor and the transverse colon, stomach and spleen was unclear, and invasion of the transverse colon as well as the stomach and spleen was suspected. Hemorrhage due to colon invasion of the pancreatic tail cancer and intra-tumoral hemorrhage were suspected. Due to persistent bleeding, the patient had emergency surgery to control bleeding. The pancreatic tail tumor invaded not only the colon but also stomach and spleen, distal pancreatectomy, partial gastrectomy and splenectomy was performed in combination with resection of the transverse colon, and transverse colon colostomy. We report a case of gastrointestinal bleeding caused by transverse colon invasion of pancreatic tail cancer, which resulted in emergency surgery.

[A Case of Medullary Carcinoma of the Colon].

The patient is a 79-year-old woman who visited her local doctor with a chief complaint of abdominal pain. A lower gastrointestinal endoscopy revealed a circumferential type 3 mass in the transverse colon. The patient was diagnosed with transverse colon cancer (cT3N0M0, cStage Ⅱa)and underwent laparoscopic transverse colectomy(D3). The postoperative course was good, and she was discharged on POD 9. Pathological results showed a diagnosis of medullary carcinoma(pT3N0M0, pStage Ⅱa)with MSI-high. The patient was treated with UFT/UZEL for 6 months as postoperative adjuvant chemotherapy. The patient has been recurrence-free for 1 year and 6 months postoperatively and is under outpatient follow-up. Medullary carcinoma is a rare histologic type that is estimated to account for 2-3% of all colorectal cancers. Medullary carcinoma of the colon is more common in elderly patients, women, and the right side of the colon, with a relatively favorable prognosis. We report a case of medullary carcinoma of the transverse colon in which the patient had a relatively long survival, with some discussion of the literature.

[A Case of Stage â £c dMMR Transverse Colon Cancer with Complete Response to Combination Therapy with Immune Checkpoint Inhibitor in Stage â £B Lung Adenocarcinoma].

The patient is a 72-year-old man. He was diagnosed as a duplication of left upper lobe lung adenocarcinoma cStage ⅣB and transverse colon cancer cStage Ⅳc. Because he had symptoms of atelectasis and esophageal stricture due to the progression of lung cancer, we decided to precede immunochemotherapy(CBDCA plus PEM plus pembrolizumab)for lung cancer. After the start of treatment, both lung and colorectal cancer were shrinking, but after the 3 courses of treatment, he developed intestinal obstruction due to transverse colon cancer. Because generalized peritonitis due to perforation of the colon by endoscopic stenting for the obstruction and then emergency surgery was performed. The resected transverse colon lesion was diagnosed as pathologically complete response. Lung cancer was also diagnosed as clinically complete response. Since his ADL decreased postoperatively, he is under observation without reintroduction of immunochemotherapy. Fourteen months have passed since the last administration, and no progression has been observed in either lung nor colon cancers. Pembrolizumab is considered to be successful in the patient with dMMR colorectal cancer lacking MLH1 and PMS2.

[A Case of Transverse Colon Cancer Associated with Lynch Syndrome with Excellent Response to Pembrolizumab].

A 47-year-old woman diagnosed with transverse colon cancer with liver, peritoneal, and lymph node metastases was admitted. Modified FOLFOX6(mFOLFOX6)regimen was given as a first line chemotherapy and was followed by pembrolizumab after 1 cycle of the mFOLFOX6, because microsatellite instability(MSI)test of the tumor showed high-frequency MSI. Because of the transverse colon obstruction after 2 cycles of pembrolizumab, she underwent right hemicolectomy. Histological examination of the resected specimen revealed no residual tumor cells in the primary tumor and reginal lymph nodes. Immunohistochemistry for mismatch repair proteins(IHC-MMR)showed loss of MSH2 and MSH6 expression. Genetic test identified a MSH2 pathogenic variant leading to the diagnosis of Lynch syndrome. The present case shows the importance of MSI test or IHC-MMR before the treatment of metastatic colorectal cancer.

[Axillary Lymph Node Recurrence after Curative Surgery for Transverse Colon Cancer-A Case Report].

We report the rare case of an 89-year-old female with axillary lymph node recurrence after curative surgery for transverse colon cancer who had undergone right hemicolectomy with D3 lymphadenectomy with an uneventful postoperative course. Pathological examination confirmed the tumor's status as tub2>sig, T4aN3M0, and pStage Ⅲc, and signet-ring cell carcinoma was remarkably found in the metastatic lymph node. Genetic testing revealed wild-type RAS, a BRAF mutation, and a high MSI. After 9 months of follow-up without adjuvant chemotherapy, CEA increased sharply to 41.3 ng/mL by 9 months postoperatively, and CT showed nodules in the right axilla, adrenal gland, and retroperitoneum. PET-CT showed abnormal fluorodeoxyglucose uptake in the same regions. A core needle biopsy of the axillary lymph node revealed signet-ring cell carcinoma, which was diagnosed as a recurrence of transverse colon cancer. Although we suggested chemotherapy due to the unresectable recurrence of colorectal cancer, she preferred to receive supportive care instead. Three months after the recurrence was diagnosed, CEA increased to 248.4 ng/mL, and CT showed enlargement of the axillary lesion and a new lesion in the hilum of the lung.

[A Case of Long-Term Survival with Metachronous Hepatic and Pulmonary Metastases from Transverse Colon Cancer by Multidisciplinary Treatment].

A 64-year-old woman underwent right hemicolectomy for transverse colon cancer. Histopathological findings revealed T, type 2, 24×22 mm, tub2, pT2N1a(1/23)M0, and pStage Ⅲa. Postoperative adjuvant chemotherapy was not administered at the patient's request. One year after surgery, carcinoembryonic antigen(CEA)level was elevated, and Gd-EOB-DTPA- enhanced MRI revealed a nodule in segment 2 and 4/8 of the liver. Based on the diagnosis of hepatic metastasis, laparoscopic partial hepatectomy was performed. Three years after hepatectomy, CEA level was found to be elevated again, and chest CT showed a solitary pulmonary nodule in segment 7 of the right lung. With a diagnosis as pulmonary metastasis, FOLFIRI plus bevacizumab was performed. After 41 courses of FOLFIRI plus bevacizumab, the pulmonary nodule decreased in size, and no new lesions appeared. The chemotherapy was terminated at the patient's request. Six months later, the pulmonary nodule increased in size, and thoracoscopic partial pulmonary resection was performed. Hepatic and pulmonary resection specimens were histopathologically consistent as metastasis of colorectal cancer. The patient has been alive without recurrence for about 4 years after final surgery(pulmonary resection)without postoperative adjuvant chemotherapy. We report a case of long-term survival with metachronous hepatic and pulmonary metastases from transverse colon cancer by multidisciplinary treatment.

[Laparoscopic Resection of a Liver and Ovarian Metastasis of Transverse Colon Cancer-A Case Report].

A 60s woman was diagnosed to transverse colon cancer and she underwent laparoscopic right hemicolectomy. Localized peritoneal dissemination surrounding tumor was detected during surgery. She was administrated to chemotherapy due to a hepatic metastasis in S2/3 postoperatively. Subsequently, PET-CT revealed a left ovarian metastasis in addition to a liver metastasis during chemotherapy. Laparoscopic hepatic left lateral segmentectomy and bilateral adnexectomy was performed at 1 year and 9 months after the first surgery and histopathological examination showed a metastasis of transverse colon cancer. The growth of liver and lung metastases and peritoneal disseminations was detected at 6 months later after the second surgery and the patient is currently receiving palliative treatment. Previous literatures described that ovarian metastasis of colon cancer showed bilateral metastasis and resistance to chemotherapy frequently and ruptured in some cases. We should consider to resect bilateral ovary even if unilateral metastasis alone was detected by imaging examination.

[A case of retrograde intussusception due to transverse colon cancer detected by abdominal ultrasonography].

A 78-year-old female patient presented to our hospital with abdominal pain and melena. Abdominal ultrasonography detected a multiple concentric ring sign and retrograde invagination mass near the hepatic flexure. Colonoscopy revealed a 40-mm diameter type 1 tumor in the transverse colon near the splenic flexure, and the biopsy specimen demonstrated a well-differentiated adenocarcinoma. Retrograde intussusception due to transverse colon cancer was diagnosed, and laparoscopic transverse colon resection with lymph node dissection was performed. The resected specimen revealed a 48×40mm diameter type 1 tumor in the transverse colon and was diagnosed as pT2N0M0 pStage I. Contrast-enhanced computed tomography was unavailable, but real-time assessment of the invaginated mass and bowel blood flow was possible by abdominal ultrasonography, which was useful in determining the diagnosis and treatment strategy.

Laparoscopic Complete Mesocolic Excision with Central Vascular Ligation (CME + CVL) for Right-Sided Colon Cancer: A New "Superior Mesenteric Artery First" Approach.

PURPOSE: It remains a technical challenge to perform "superior mesenteric artery (SMA) first" approach for laparoscopic right hemicolectomy with complete mesocolon excision (CME) as the vascular anatomy of the right colon varies a lot, which may cause difficulty in early location of SMA and the risk of vascular damage during central vascular ligation (CVL). The purpose of this study was to describe a new "SMA first" approach for laparoscopic CME with CVL in right hemicolectomy with Treitz's ligament and ileocolic vascular pedicle as the anatomical landmarks for early identification of and exposure of SMA. METHODS: This procedure was performed on 21 patients with right colon cancer between March 2020 and August 2021. To start, the transverse mesocolon was retracted to expose the ligament of Treitz, and the pedicle of ileocolic vessels was anteriorly grasped. Next, the peritoneum near the right border of the ligament of Treitz was divided along the left side of SMA until the peritoneum below the ileocolic vessels. Next, the mesenteric lymphatic adipose tissue outside of the sheath of SMA was dissected from medial to lateral. Then, laparoscopic right hemicolectomy with complete mesocolic excision (CME) was performed. Patients' preoperative baseline characteristics and intraoperative and postoperative complications were examined. RESULTS: The median operative time was 180 min, and the median intraoperative blood loss was 50 ml (interquartile range 40-90). Chylous leakage occurred in four patients, and all the patients resolved with percutaneous drainage. The total harvested lymph nodes was 21.0 (range 16-27). The median times to first flatus and liquid diet intake were both 3.0 days. The median number of postoperative hospital days was 10.0 days. No severe postoperative complications, such as abdominal infection, anastomotic leakage, or bleeding, were observed. CONCLUSIONS: This new "SMA first" approach is safe and technically feasible for laparoscopic CME with CVL in right hemicolectomy.

Mid-transverse Location in Primary Colon Tumor: A Poor Prognostic Factor?

BACKGROUND: The location of colonic tumors has been linked to different clinical and oncologic outcomes. Transverse colon cancers are generally included as right colon cancers. Furthermore, hepatic and splenic flexure tumors are usually included as components of the transverse colon. OBJECTIVE: This study was aimed at comparing the clinicopathologic characteristics and long-term outcomes between mid-transverse and right and left colon cancers and determining the prognostic impact of the primary tumor location in the mid-transverse colon. DESIGN: This was a retrospective study. SETTINGS: Two specialized colorectal centers were included. PATIENTS: Patients who underwent curative surgery for colon cancer were analyzed. Tumors located in the transverse colon, excluding the flexures, were defined as mid-transverse colon cancers. MAIN OUTCOME MEASURES: Demographic characteristics, operative outcomes, pathologic results, and long-term outcomes were the primary outcome measures. RESULTS: Of the 487 patients, 41 (8.4%) had mid-transverse, 191 (39.2%) had right, and 255 (52.4%) had left colon cancers. For mid-transverse colon cancers, the mean length of hospital stay, mean length of the resected specimen, and the mean number of harvested lymph nodes were significantly higher. For patients with stage I to III cancer, the 5-year overall and disease-free survival rates were significantly worse in the mid-transverse colon cancers than in the right and left colon cancers (overall survival: 55.5% vs 82.8% vs 85.9%, p = 0.004, and disease-free survival; 47.7% vs 72.4% vs 79.5%, p = 0.003). After adjustment for other clinicopathologic factors, mid-transverse colon cancers were significantly associated with a poor prognosis (HR = 2.19 [95% CI, 1.25-3.83]; p = 0.006). LIMITATIONS: Molecular and genetic information were unavailable in this retrospective study. CONCLUSIONS: In our case series, colon cancers located in the mid-transverse colon showed poorer prognosis than cancers in other locations. The impact of tumor location in the mid-transverse colon on prognosis, including molecular and genetic markers, should be investigated further in prospective studies. See Video Abstract at http://links.lww.com/DCR/B631. LOCALIZACIN TRANSVERSA MEDIA EN EL TUMOR DE COLON PRIMARIO UN FACTOR DE MAL PRONSTICO: ANTECEDENTES:La ubicación de los tumores de colon se ha relacionado con diferentes resultados clínicos y oncológicos. Los cánceres de colon transverso se incluyen generalmente como cánceres de colon derecho. Además, los tumores del ángulo hepático y esplénico suelen incluirse como un componente del colon transverso.OBJETIVO:Este estudio tuvo como objetivo comparar las características clínico-patológicas y los resultados a largo plazo entre los cánceres de colon transverso medio y derecho e izquierdo y determinar el impacto pronóstico de la ubicación del tumor primario en el colon transverso medio.DISEÑO:Este fue un estudio retrospectivo.AJUSTE ENTORNO CLINICO:Se incluyeron dos centros colorrectales especializados.PACIENTES:Se analizaron los pacientes que fueron sometidos a cirugía curativa por cáncer de colon. Los tumores ubicados en el colon transverso, excluidos los ángulos, se definieron como "cánceres de colon transverso medio".PRINCIPALES MEDIDAS DE RESULTADO VOLARACION:Las características demográficas, los resultados quirúrgicos, los resultados patológicos y los resultados a largo plazo fueron las principales medidas de resultado valoracion.RESULTADOS:De los 487 pacientes, 41 (8,4%) tenían cáncer de colon transverso medio, 191 (39,2%) derecho y 255 (52,4%) cáncer de colon izquierdo. Para los cánceres de colon transverso medio, la duración media de la estancia hospitalaria, la duración de la muestra resecada y el número medio de ganglios linfáticos extraídos fueron significativamente mayores. Para los pacientes en estadio I-III, las tasas de supervivencia general y sin enfermedad a 5 años fueron significativamente peores en los cánceres de colon transverso medio que en los cánceres de colon derecho e izquierdo (supervivencia general: 55,5% frente versus a 82,8% frente versus a 85,9%, p = 0,004 y supervivencia libre de enfermedad; 47,7% frente a 72,4% frente a 79,5%, p = 0,003, respectivamente). Después del ajuste por otros factores clínico-patológicos, los cánceres de colon transverso medio se asociaron significativamente con un pronóstico desfavorable (Razón de riesgo: 2,19; intervalo de confianza del 95%: 1,25-3,83; p = 0,006).LIMITACIONES:La información molecular y genética no estuvo disponible en este estudio retrospectivo.CONCLUSIONES:En nuestra serie de casos, los cánceres de colon localizados en el colon transverso medio mostraron un peor pronóstico que los cánceres en otras localizaciones. El impacto de la ubicación del tumor en el colon transverso medio sobre el pronóstico, incluidos los marcadores moleculares y genéticos, debe investigarse más a fondo en estudios prospectivos. Consulte Video Resumen en http://links.lww.com/DCR/B631. (Traducción-Dr Adrián Ortega).