[A Case of BRAF Mutant Cecal Cancer Treated with Encorafenib, Binimetinib, and Cetuximab Triple Therapy].

A Japanese woman in her early 70's presented to our hospital with abdominal pain and nausea. Abdominal computed tomography showed irregular wall thickening of the ileocecal region and small intestine dilatation. Colonoscopy revealed a tumor lesion at the ileocecal valve and adenocarcinoma was detected in the biopsy specimen. Accordingly, the diagnosis was cecal cancer and bowel obstruction. Right hemicolectomy was performed as palliative surgery, and laparotomy findings revealed peritoneal dissemination. The final staging was pT4a, pN2b, pM1c, pStage Ⅳc, harboring a BRAFV600E mutation. Rapid postoperative tumor progression occurred, leading to multiple liver metastases and ascites. Encorafenib, binimetinib, and cetuximab triple therapy was started as a second line regimen. The therapy was extremely effective. CA19-9 level decreased to within normal range, and the liver tumor size was visibly diminished. After receiving treatment for 2 months in outpatient care, she had to discontinue the treatment due to carcinomatous peritonitis. Unfortunately, she died 6 months after initial diagnosis. BRAF-mutated colon cancer is associated with poor prognosis. In Japan, encorafenib, binimetinib, and cetuximab triple therapy is a new BRAF targeting regimen approved in 2020. We report this clinical course in hopes of eventually achieving better outcomes for patients with this aggressive disease.

[A Case of Early-Stage Cecal Cancer with Mesenteric Phlebosclerosis Requiring Laparoscopic Right Hemicolectomy of the Colon].

The patient was a 71-year-old woman diagnosed with mesenteric phlebosclerosis(MP)2 years earlier. CT performed to investigate her abdominal pain revealed an ascending colon obstruction. Colonoscopy(CS)revealed MP extending to the ascending colon hepatic flexure with stenosis and a cecal tumor(biopsy tub1). Although the cancerous lesion itself was potentially curable by endoscopic treatment, it was surgically resected because of the ascending colon stenosis caused by the MP that had also caused intestinal obstruction. Intraoperative findings revealed wall thickening and stiffening from the cecum to the ascending colon hepatic flexure. Postoperative pathological examination revealed cecal carcinoma pTis, N0, M0, pStage 0. The background mucosal tissue was consistent with MP, but no findings suggested a relationship between the MP and tumor. Although the relationship between MP and carcinogenesis is unknown, and no such relationship was identified in this case, we report this case because a further accumulation of cases of MP and carcinoma is necessary, considering the rarity of MP itself and the non-negligible number of cases with carcinoma.

[A Case of Concentrated Ascites Reinfusion Therapy(CART)for Abundant Refractory Ascites in Cecal Cancer with Peritoneal Dissemination Followed by the Readministration of Chemotherapy].

A 66-year-old man underwent laparoscopic ileocecal resection for cecal cancer with liver metastasis(cT3N1M1a, cStage Ⅳa). One month later, combination chemotherapy with capecitabine, oxaliplatin, and bevacizumab was administered for liver metastasis. However, during the treatment, peritoneal dissemination and abundant diuretic-resistant ascites was revealed, resulting in poor dietary intake. One year and 11 months after the surgery, the chemotherapy was interrupted and cell-free and concentrated ascites reinfusion therapy(CART)was undergone as palliative care. The initial volume of retrieved ascites was 6,500 mL, and the volume was increased gradually to a maximum of 14,020 mL without hemodynamic instability. Totally CART was administered 10 times during 7 months without any complications: mean volume of retrieved ascites; 9,780 mL/unit, the interval between therapies; 2-3 weeks. Serum albumin level did not decrease since CART administration. His oral intake and daily activities were improved by CART. These clinical outcomes contributed to the readministration of chemotherapy. We present a recent case of safe and periodical CART for abundant refractory ascites in cecal cancer with peritoneal dissemination, resulting in the improvement of QOL and the readministration of chemotherapy.

Pseudo-submucosal tumor in the colon: seeing is believing.

A 65-year-old woman was admitted to our hospital with complaints of lower abdominal pain. Her physical examination was unremarkable. The results of routine laboratory testing were within the normal limits. In addition, abdominal CT was normal. Colonoscopy showed a cecum submucosal tumor with a pale yellow surface. Endoscopic ultrasound revealed homogeneous hypoechoic lesions originated from submucosal layer. ESD was subsequently performed to remove the submucosal lesion. During the ESD procedure, fecal outflowed from appendix opening . Yellow fecal-like material was visible after submucosal incision. The trap electrocut surface uplift showed more fecal attachment on the lamina propria surface, and myolayer integrity after clean the fecal (Fig1c), The final pathology of the surface bulge suggested hyperplasia (Fig1d). Patients were discharged with relieved lower abdominal pain. The final diagnosis was submucosal fecalith mimicking a submucosal tumor, eventually leads to chronic appendicitis. Common causes of cecal submucosal tumor include neuroendocrine tumors, lipomas, etc. There was few report about fecalith mimicking a submucosal tumor. ERTA is currently an effective endoscopic method for treating appendicitis combined with fecalith blockage. To our knowledge, this is the first report on a case of cecum submucosal fecalith mimicking a submucosal tumor and was successfully removed using endoscopy.

Pathways of lymph node metastasis and prognosis after right hemicolectomy for cecal cancer: results from a retrospective single center.

BACKGROUND: The recommended operation for cecum cancer (CC) is right hemicolectomy (RH) in some Western countries while the principle of D3 lymphadenectomy in Japan recommends resecting approximately 10 cm from the tumor edge. Therefore, the optimal surgical approach for cecum cancer (CC) remains controversial. We conducted this retrospective study to explore the pattern of lymph node metastasis and better surgical procedures for CC. METHODS: A total of 224 cecum cancer patients from January 1, 2014, to December 31, 2021, were retrospectively included in the final study. The pattern of lymph node metastasis (LNM) was investigated. RESULTS: A total of 113 (50.4%, 113/224) patients had pathologically confirmed LNM. The most frequent metastatic site was no. 201 lymph node (46%, 103/224), while 20 (8.9%, 20/224) patients had LNM in no. 202 lymph node, and 8 (3.6%, 8/224) patients had LNM in no. 203 lymph node. Only 1 (0.4%, 1/224) patient had LNM in no. 221 lymph node, four (1.8, 4/224%) patients had LNM in no. 223 lymph node, and no patients had LNM in no. 222 lymph node. LNM in no. 223 lymph node was significantly associated with a poor prognosis. Multivariate analysis indicated that LNM in no. 223 lymph node (HR = 4.59, 95% CI 1.18-17.86, P = 0.028) was the only independent risk factor associated with worse disease-free survival (DFS). CONCLUSIONS: The LNM in no. 223 lymph node for cecum cancer was rare. Therefore, standard right hemicolectomy excision is too extensive for most CC cases.

Is 10 cm ileal resection sufficient in locally advanced caecal cancer surgery?

BACKGROUND: There is no consensus as to how much ileal resection is sufficient when performing a right hemicolectomy for right colon cancers. Locally advanced caecal cancer has the highest incidence of peri-ileal lymph node metastasis. Therefore, this study investigated whether the 10 cm ileum resection suggested by the Japanese Society for Cancer of the Colon and Rectum is oncologically safe in stage II and III caecal cancer. METHODS: The prospectively collected medical records of stage II and III caecal cancer patients who underwent a right hemicolectomy with at least D2 lymph node dissection were reviewed retrospectively. The patients were divided into two groups according to the length of proximal ileal resected: group 1 (≤10 cm) and group 2 (>10 cm). Factors contributing to the 5-year overall survival (OS) were analysed. RESULTS: The study enrolled 89 patients with pathological stage II or III caecal cancer. The >10 cm group tended to be younger (P = 0.0938) with higher pathological N stages (P = 0.0899) than the ≤10 cm group. The 5-year OS did not differ between the two groups. No significant difference was found between the two groups according to stage. Age (HR = 1.06, 95% CI = 1.02-1.10, P = 0.0069) and N2 stage (HR = 5.38, 95% CI = 1.90-15.28, P = 0.0016) were significantly associated with OS in both uni- and multivariate analyses. CONCLUSIONS: There was no OS benefit to resecting >10 cm of ileum in either stage II or III caecal cancer patients. Hence, we suggest that the '10 cm rule' is sufficient for stage II and III caecal cancer patients.

[A Case of Inguinal Hernial Sac Metastasis of Cecal Cancer Resected with TAPP Approach].

Malignant tumor occurring in the inguinal region are relatively infrequent, and metastatic tumor is extremely rare. We report a case of inguinal hernial sac metastasis of cecal cancer resected with TAPP approach. The case is a 80's man. One year and 6 months after cecal cancer surgery, contrast-enhanced computer tomography(CT)examination revealed a solitary tumor in the right inguinal canal. We diagnosed inguinal hernia sac metastasis of cecal cancer and performed surgery. The mass in the hernia sac was resected with the TAPP approach. Histopathological findings were consistent with peritoneal metastasis directly to the inguinal hernia sac. The patient has been alive without 2 years after metastasectomy. It is necessary to treat patients with a history of malignant disease with keeping the possibility of inguinal hernia sac metastasis in mind.

Ascending colon cecal junction carcinoma with prostate metastasis: A case report and literature review.

RATIONALE: Colon carcinoma is the most common type of cancer, and a leading cause of cancer-related death. Clinically, the most common sites of metastases from colon carcinoma are the liver, lungs, peritoneum, and lymph nodes, while the incidence of metastases to the prostate is low. There are few relevant studies on colon carcinoma, most of them being case reports. PATIENT CONCERNS: A 76-year-old man treated with radical resection of right colon carcinoma due to primary poorly differentiated adenocarcinoma of the cecum. Postoperative pathological examination suggested that he had cancer at the junction of the ascending colon and the cecum. He had received adjuvant chemotherapy after surgery. One year later, he received transurethral plasma resection of the prostate due to urinary system discomfort. Postoperative pathological immunohistochemistry suggested prostate metastasis of colorectal carcinoma, and he received individualized treatment, but this produced no clear survival benefit. DIAGNOSES: Ascending colon cecal junction carcinoma with prostate metastasis. INTERVENTIONS: Radical resection, chemotherapy, anti-androgen therapy, surgery to relieve primary lesion obstruction symptoms, and local radiotherapy of the prostate. OUTCOMES: At present, clinical cases of colon carcinoma with prostate metastasis are rare. By sharing a rare case of ascending colon cecal junction carcinoma with prostate metastasis and reviewing the relevant literature, this paper explores and optimizes the clinical treatment of colon carcinoma with prostate metastasis.

[A Case of Cecal Cancer Diagnosed from Sister Mary Joseph's Nodule].

A metastatic tumor of the umbilicus is called"Sister Mary Joseph's nodule", and patients with this tumor show a poor prognosis. Sister Mary Joseph's nodule is a rare occurrence, and there are few case reports. We report a case of cecal cancer first presented with the metastatic tumor in the umbilicus. A 90-year-old woman, complained umbilical induration and foul-smelling discharge, had been treated as omphalitis for 2 months. Because her symptom didn't improve, biopsy of the umbilical tumor was performed, and the findings revealed an adenocarcinoma. She was referred to our hospital. Abdominal CT showed wall thickening in the cecum, and multiple liver metastases. Therefore, we performed lower gastrointestinal endoscopy, which revealed a cecal tumor. We performed biopsy of the tumor and the findings were consistent with adenocarcinoma. Based on these results, we diagnosed the umbilical tumor as a metastasis from the colorectal cancer. Umbilical resection and ileocecal resection were performed, and multiple peritoneal metastases was detected. Post operative course was uneventful, she died 11 months after surgery. Umbilical metastases may worsen the patient's quality of life; thus, the local resection of umbilicus was recommended positively.

[Liver Resection after Chemotherapy for Simultaneous Liver Metastasis of Cecal Cancer-A Case Report].

A 78-year-old male patient was referred to another hospital for cecal cancer and metastatic liver tumor. After open ileocecal resection, he was referred to our hospital for treatment of liver lesions. CT scan showed a lesion with contrast effect of approximately 60 mm in S8, and the patient was judged to be resectable by right lobe resection. However, considering his age and the possibility of latent disease, it was decided to introduce preoperative chemotherapy. After 4 courses of XELOX, although the ICG worsened from 9% to 18% after chemotherapy, the tumor was reduced to approximately 30 mm. The patient underwent an open anterior segment resection of the liver. Colorectal cancer guidelines recommend that surgical resection is the first-line treatment for resectable liver metastases and that preoperative adjuvant chemotherapy should not be given to patients. In this report, we describe a case in which a liver metastasis was safely resected with chemotherapy.

[A Case of Two-Stage Radical Resection with Neoadjuvant Chemotherapy for Cecal Cancer with Synchronous Peritoneal Metastasis(P3)].

A 63-year-old female patient was diagnosed with cecal cancer(cT3, N2a, M0)and underwent surgery for the first time. Only laparoscopic ileocecal resection(D3 dissection)was performed because intraperitoneal observation revealed peritoneal metastasis around the tumor and uterus. We decided to perform a radical resection because the peritoneal metastasis was localized by FDG-PET/CT. Five courses of neoadjuvant chemotherapy(mFOLFOX6)were performed to shrink the tumor. Unrecognized peritoneal metastases were found in other areas during the second surgery. Although the extent of the peritoneal metastasis was P3, all lesions had been resected. No perioperative complications occurred, and adjuvant chemotherapy was administered to the patient. Recurrence was not observed until 6 months postoperatively.

Surgical Resection for Local and Lateral Lymph Node Recurrence of MSI-high Cecal Cancer with the BRAF V600E Mutation.

An 84-year-old female underwent open right hemicolectomy with D3 lymph node dissection for cecal cancer, pathologically identified as pT4aN2M0 Stage IIIc and BRAF mutation-positive. Due to early recurrence of abdominal wall and right lateral lymph nodes, the patient was treated with FOLFOXIRI+Bevacizumab. Imaging after 5 courses of chemotherapy found tumor shrinkage and no new metastases. The patient did not tolerate chemotherapy well, and tumor resection was performed. Microsatellite instability (MSI) testing using multiplex polymerase chain reaction (PCR) fragment analysis revealed MSI-high status. The patient is currently recurrence-free without chemotherapy at 1 year postoperatively. BRAF-mutated colorectal cancer has a poor prognosis, and may require resection of the metastatic or recurrent tumor after comprehensive evaluation.

Anatomical challenge: a rare coexistence of caecal cancer and isolated duodenal malrotation.

Intestinal malrotation is a congenital anomaly, treated mostly during childhood. A small number of cases are incidentally found in adulthood, during operation for other abdominal diseases, such as colon cancer.Here, we present a case of caecal cancer with isolated duodenal malrotation, a subtype of intestinal malrotation, discovered incidentally during the operation for the cancer. Although the anatomical abnormality made the operation more complicated, laparoscopic resection was safely performed with oncologically adequate lymphadenectomy, owing to intraoperative confirmation of anatomy and careful dissection.

Literature review of imaging, pathological diagnosis, and outcomes of metachronous lung and pancreatic metastasis of cecal cancer.

BACKGROUND: Pancreatic metastasis from colorectal cancer is extremely rare. Here, we report a case of colorectal cancer with lung and pancreatic metastasis and analyze the histopathology, immunohistochemistry, and next-generation sequencing (NGS) to generate a differential diagnosis and treatment of metastatic colon cancer. CASE PRESENTATION: AC1 A 78-year-old man was admitted because of a recently elevated carcinoembryonic antigen. This patient had undergone laparoscopic right hemicolectomy for cecal cancer IIA (T3N0M0) 5 years before admission, and thoracoscopic left upper lung wedge resection for primary colon cancer lung metastasis 2 years before admission. At that time, the patient was thought to have pancreatic metastasis from colon cancer. He underwent laparoscopic distal pancreatectomy (combined with splenectomy). Postoperative pathology revealed colon cancer metastasis. We performed NGS on tumor samples at three loci and found colon cancer's most common oncogenic driver genes (KRAS, APC, and TP53). One month after surgery, the patient was given capecitabine for six cycles of chemotherapy. At present, no high adverse reactions have been reported. DISCUSSION: For patients with pancreatic space-occupying, such as a previous history of colorectal cancer, and recent carcinoembryonic antigen elevation, we should highly suspect pancreatic metastatic colorectal cancer. NGS is an essential auxiliary for identifying metastatic tumors. Surgery combined with postoperative chemotherapy is an effective treatment.

[A Case Report of Psoas Abscess Formation Caused by Mucinous Cystadenocarcinoma].

We report a rare case of psoas abscess formation caused by mucinous cystadenocarcinoma. A 65-year-old women was admitted to our hospital for treatment for iliopsoas abscess. She presented with standing difficulty and her laboratory data showed an increased level of leukocytes. CT scan demonstrated an abscess formation in iliopsoas muscle. Colonoscopy showed an ulcer on her cecum. Although percutaneous drainage was performed on the first day, the abscess relapsed repeatedly. Ileocolectomy was performed on post admission day 29. Abscess drainage continued after the operation, the patient was discharged on postoperative day 34. Pathological examination revealed mucinous cystadenocarcinoma on the cecal tumor. Total 8 cycles of FOLFOX6 was performed as adjuvant chemotherapy. The patient has been survived for 20 months with no recurrence.