Adenocarcinoma Of Sigmoid Colon Research Articles

Colon Cancer with Complete Pathological Response to Only 1 Cycle of Capecitabine: Treatment Modification in the Perspective of COVID-19 Pandemic

Incidence of colorectal cancer has surged in the past few decades, currently it accounts for approximately 10% cancer related mortality. Upfront curative surgery is the main stay of treatment for localized disease followed by adjuvant chemotherapy for high-risk disease; however, neo adjuvant chemoradiation followed by surgery and chemotherapy is a standard treatment for rectal cancer. Here, we present a case of a young male aged 33 years with eight months’ history of per rectal bleeding, associated with fever and weight loss who was later diagnosed as sigmoid colon adenocarcinoma. The patient managed to have only one cycle of neoadjuvant capecitabine, as his definitive surgery was delayed due to the rife in pandemic situation of Covid-19. Notably, follow up laparoscopic LAR specimen showed no residual disease, nevertheless, there was an eosinophilic abscess with a giant cell reaction and Ova of Ascaris lumbricoides, which seemingly contributed in achieving pathological complete response with minimal therapy.

Anesthesia Management of Venous Gas Embolism with Hepatectomy

Abstract Background: This is a case review of the intraoperative management of a 46 year old male patient with a history of stage IV sigmoid colon adenocarcinoma with metastasis to the liver that presented for a robotic assisted sigmoidectomy and partial hepatectomy and had an intraoperative venous gas embolism that resulted in acute hemodynamic instability. Description of the case: A robotic assisted sigmoidectomy and partial hepatectomy was performed on a 46 year old male patient with a history of stage IV sigmoid colon adenocarcinoma with metastasis to the liver. The patient was otherwise healthy with no other significant medical history, and the perioperative lab results were within normal ranges with the exception of elevated liver function test results. The patient received preoperative medications for multimodal pain management as part of the enhanced recovery after surgery (ERAS) protocol and had an uneventful induction with intravenous anesthetic induction and endotracheal intubation. During the intraoperative course, the patient exhibited an acute hypotensive episode followed by acute desaturation. A venous gas embolism was suspected, and immediate interventions were implemented which helped the patient stabilize. The patient remained hemodynamically stable throughout the remainder of the case. After surgery, the patient was admitted to the intensive care unit for postoperative monitoring for any neurological or cardiovascular effects related to the intraoperative venous gas embolism. The postoperative period was uneventful, and the patient was successfully discharged home several days later without any adverse sequelae. Discussion and conclusions: Venous gas embolism can be a life-threatening intraoperative event that requires fast recognition of the symptoms and appropriate interventions in response to the patient changes. Evidence suggests that venous gas embolisms are very common with certain procedures but often subclinical. Preventative measures, early recognition, and prompt treatment of venous gas embolisms are important interventions to minimize the risk for any significant hemodynamic instability and any resulting neurological or cardiovascular sequelae.

Asymptomatic chronic suppurative cholecystitis and peritonitis mimicking metastasis by 18F-FDG PET/CT scan during sigmoid colon cancer surveillance

The study describes an unusual case that a patient with previous history of adenocarcinoma of sigmoid colon who has developed chronic suppurative cholecystitis and peritonitis was misdiagnosed as metastasis. This case is presented to illustrate the importance of considering benign etiologies that may mimic metastatic disease when interpreting positron emmision tomography (PET)/CT scans.

Sigmoid colon adenocarcinoma incarcerated in an inguinoscrotal hernia: diagnostic and management challenges.

Sigmoid colon adenocarcinoma incarcerated in an inguinoscrotal hernia: diagnostic and management challenges.

Применение панитумумаба в терапии химиорезистентной метастатической аденокарциномы сигмовидной кишки: клинический случай

Применение панитумумаба в терапии химиорезистентной метастатической аденокарциномы сигмовидной кишки: клинический случай

Identification of the HT-29 cell line as a model for investigating MCT1 transporters in sigmoid colon adenocarcinoma

MCT1 transporters play a crucial role in the symbiotic relationship between humans and their colonic microbiome by facilitating the transport of bacteria-derived short chain fatty acids. Expression of colonic MCT1 transporters, localized in surface epithelial cells, is regulated by luminal butyrate levels. However, MCT1 also transports lactate and can be used by cancer cells to facilitate anaerobic glycolysis. Using immunolocalization techniques, this study investigated whether changes in MCT1 during cancer varied between different colonic regions. Whilst MCT1 abundance did not significantly change in transverse colon adenocarcinoma (P = 0.363, N = 6, paired T-Test), there was an increase in MCT1 in sigmoid colon adenocarcinoma (P = 0.010, N = 21, paired T-test). Using RT-PCR and western blotting, three human intestinal cell lines were tested for their suitability as a MCT1 cancer cell model. Experiments with Caco-2 cells confirmed that they modelled normal cells, with MCT1 only expressed after exposure to butyrate. In contrast, MCT1 was expressed in the absence of butyrate in both HCT-8 and HT-29 cell lines, with consistently high levels of MCT1 protein being present in HT-29 cells. Furthermore, butyrate treatment of HT-29 cells significantly decreased both MCT1 protein abundance (P < 0.001, N = 4, unpaired T-test) and glycosylation of its’ chaperone protein, CD147 (P < 0.001, N = 4, unpaired T-test). These data suggest that (i) MCT1 transporter abundance increases in sigmoid colon adenocarcinoma, and (ii) HT-29 cells are an appropriate cell model with which to investigate MCT1 function in this disease.

A new aggressive xenograft model of human colon cancer using cancer-associated fibroblasts.

BackgroundColorectal cancer is the second leading cause of cancer death. Almost half of the patients present recurrence within 5 years after the treatment of the primary tumor, the majority, with metastasis. On the other hand, in the search for new animal models that simulate metastatic cancer, it has been suggested that fibroblasts immersed in the peritumoral stroma (cancer-associated fibroblasts (CAFs)), play a relevant role in the development of cancer. The objective of this study was to identify an adequate animal model to study metastatic colon cancer and the application of new treatments.MethodsHuman CAFs and normal fibroblasts (NF) for transplant and culture were obtained from surgical fresh samples of patients with adenocarcinoma of sigmoid colon. Stromal cell purity was evaluated by morphology and immunostaining with vimentin (VIM) as a fibroblast marker and anti-proColXIα1 as a specific human CAF marker. Phenotypic characterization of cultured stromal cells was performed by co-staining with mesenchymal and epithelial cell markers. For identification in mice, human CAFs were labeled with the PKH26 red fluorescence dye. Cell line HT-29 was used as tumor cells. Transplant in the head of the pancreas of 34 SCID mice was performed in four different groups, as follows: I. 150,000 CAFS (n = 12), IIa. 1.5 million HT29 cells (n = 7), IIb. 150,000 NF+1.5 million HT29 cells (n = 5), III. 150,000 CAFS+1.5 million HT29 cells (n = 10). After euthanasia performed one month later, histological analysis was made using hematoxylin–eosin and anti-proColXIα1. A histopathological score system based on three features (tumor volume, desmoplasia and number of metastasized organs) was established to compare the tumor severity.ResultsThe CAFs and NF cultured were proColXIα1+/VIM+, proColXIα1/alphaSMA+ and proColXIα1+/CK19+ in different proportions without differences among them, but the CAFs growth curve was significantly larger than that of the NF (p < 0.05). No tumor developed in those animals that only received CAFs. When comparing group II (a + b) vs. group III, both groups showed 100% hepatic metastases. Median hepatic nodules, tumor burden, lung metastases and severity score were bigger in group III vs group II (a + b), although without being significant, except in the case of the median tumor volume, that was significantly higher in group III (154.8 (76.9–563.2) mm3) vs group II (46.7 (3.7–239.6) mm3), p = 0.04. A correlation was observed between the size of the tumor developed in the pancreas and the metastatic tumor burden in the liver and with the severity score.ConclusionOur experiments demonstrate that cultured CAFs have a higher growth than NF and that when human CAFs are associated to human tumor cells, larger tumors with liver and lung metastases are generated than if only colon cancer cells with/without NF are transplanted. This emphasizes the importance of the tumor stroma, and especially the CAFs, in the development of cancer.

CUSTOMIZING AIRWAY STENT FOR MULTICENTRIC MALIGNANT AIRWAY OBSTRUCTION

TYPE: Abstract Publication TOPIC: Procedures PURPOSE: A middle-aged man with adenocarcinoma of sigmoid colon and solitary liver metastasis underwent neoadjuvant chemotherapy followed by hemicolectomy and hepatectomy. The cancer progressed and he developed endobronchial metastasis resulting in near-total obstruction of left main bronchus (LMB) and bilateral pulmonary nodules. METHODS: Laser photoresection of LMB tumor was performed followed by covered self-expanding metallic stent (SeMS). He received radiation and anti-angiogenic therapy. Six months later, he complained of worsening dyspnea and stridor. CT Thorax revealed complete occlusion of the distal end of stent with collapse of left lung. Rigid bronchoscopy revealed tumor in-growth through the stent; tumor at the main carina causing 70% obstruction of the right main bronchus (RMB), and a polypoidal mass arising from the right middle lobe bronchus. Tumor debulking was performed within the stent and at the carina with argon plasma coagulation (APC) and rigid forceps, and the polypoidal mass was removed with electrosurgical snare. The left limb of silicone Y stent was cut to accommodate the SeMS while another circular cut was made just beyond the take-off of the right limb. The right limb of Y stent was deployed into bronchus intermedius, the circular cut maintained aeration to the right upper lobe (RUL). Post procedural CXR showed re-expansion of the left lung with satisfactory position of the silicon and SeMS stents. RESULTS: Figure 1. Bronchoscopic images CONCLUSIONS: Complex Airway Obstruction interferes with airflow and insertion of airway stents provide relief and complement ablative techniques. Modification of stents may prove to be beneficial to these patients. CLINICAL IMPLICATIONS: Please refer above DISCLOSURE: No significant relationships. KEYWORDS: central airway obstruction, airway stent

Pancreatic resection in patients with synchronous extra-pancreatic malignancy: outcomes and complications.

Patients may present with a resectable pancreatic tumour in the context of a concurrent primary extra-pancreatic malignancy. These patients pose a dilemma regarding their suitability for surgery. We evaluated our experience with such patients who underwent pancreatic resection with curative intent and detailed their outcomes and rationale for surgical decision-making. A retrospective review of patients with pancreatic concurrent extra-pancreatic primary malignancy who underwent pancreatic resection at our institution over a 12-year period (2005-2016) was performed. Clinical, histopathological and perioperative outcomes were reviewed. Ten patients with a median age of 74 years (40-85 years) were identified. Secondary primary tumours included thyroid (n = 2), gastrointestinal (n = 4), small bowel neuroendocrine (n = 1), renal (n = 1) and haematological malignancies (n = 2). Pancreatic tumours included pancreatic ductal adenocarcinomas (n = 6), solid pseudopapillary neoplasms (n = 2) and ampullary carcinomas (n = 2). After a median follow up of 41.3 months (31.3-164 months), 8 of 10 patients were still alive. Two patients died due to metastatic disease from the secondary malignancy (small bowel neuroendocrine tumour and sigmoid colon adenocarcinoma). The post-operative complication rate was 30% with no perioperative 90-day mortality. Selected patients with a pancreatic and concurrent primary extra-pancreatic malignancy may undergo curative pancreatic resection with favourable outcomes.

Filiform polyposis with sigmoid colon adenocarcinoma: a case report

BackgroundFiliform polyposis is a rare form of inflammatory polyposis, which is occasionally formed in the colon of patients with history of inflammatory bowel disease (IBD). It is characterized by presence of several to hundreds of slender, worm-like polyps in the colon lined by histologically normal colonic mucosa and often coalesce, resulting in a tumor-like mass. Filiform polyposis is most frequently associated with a post-inflammatory reparative process in patients with IBD history, and only cases of filiform polyposis occurring in patients without IBD history have been reported. Filiform polyposis has been considered as a benign inflammatory polyposis without any risk of dysplasia, while the possibility of carcinogenesis of inflammatory polyps is not fully excluded. To date, only three cases of filiform polyposis coexisting with dysplasia have been reported.Case presentationA 59-year-old male patient with no past medical history of IBD underwent laparoscopic sigmoidectomy for obstructive filiform polyposis, which was associated with sigmoid colon adenocarcinoma. Based on the histological findings of the resected specimen, invasive sigmoid colon adenocarcinoma was surrounded by filiform polyposis, and adenocarcinoma also scattered uniformly on the surface of filiform polyposis. In immunohistochemistry, abnormal p53 expression was observed in adenocarcinoma, while it was not shown in mucosa on filiform polyposis.ConclusionsThis is the fourth case of filiform polyposis that is closely associated with colon dysplasia or adenocarcinoma based on histological findings. However, immunohistochemical findings did not support the theory that inflammation initiates adenocarcinoma in filiform polyposis like IBD. Hence, further immunohistochemical and genetic analyses are needed to clarify the association between filiform polyposis and carcinogenesis.

Urachal Mucinous Cystic Tumor of Low Malignant Potential with Concurrent Sigmoid Colon Adenocarcinoma

Urachal mucinous tumors are rare neoplasms with behaviour that can range from relatively benign to malignancy that can spread distantly or throughout the peritoneum as pseudomyxoma peritonei or peritoneal carcinomatosis. Here we describe a unique case of urachal mucinous cystic tumor of low malignant potential confined to an intact cyst at the dome of the urinary bladder, without rupture or peritoneal spread. The urachal mucinous tumor was an incidental finding on a staging CT scan performed for sigmoid colon adenocarcinoma. We believe that this case illustrates a potential diagnostic pitfall which could have prognostic and therapeutic implications. Due to the intestinal phenotype of these neoplasms, a urachal tumor of low malignant potential could be mistaken for metastatic spread from a colonic adenocarcinoma in the rare situation such as this case, where the two neoplasms occur concurrently.

False-positive elevated CEA during colon cancer surveillance: a cholecystitis case report diagnosed by PET-CT scan

A 53-year-old man with previous history of sigmoid colon adenocarcinoma who had undergone surgical resection and adjuvant chemotherapy presented with slightly rising carcinoembryonic antigen (CEA), while anatomical imaging modalities were unremarkable. FDG PET-CT study did not identify residual tumoral disease; however, there were abnormalities in the gallbladder most likely suggestive of cholecystitis. Eight weeks after cholecystectomy, serum CEA concentration reached normal values. Final histopathology of the gallbladder was also consistent with acute on chronic cholecystitis.

Metachronous metastasis to inguinal lymph nodes from sigmoid colon adenocarcinoma with abdominal wall metastasis: a case report

BackgroundInguinal lymph node metastasis from rectum is uncommon but well-known occurrence, whereas that from colon adenocarcinoma is extremely rare. Inguinal lymph node metastasis from colon adenocarcinoma has only been reported in previous cases involving primary tumor invasion of the abdominal wall, or in those involving colon cancer metastasis to external iliac lymph nodes. We describe a case of inguinal lymph node metastasis from colon cancer without primary tumor invasion to the abdominal wall.Case presentationA 42-year-old female, who had undergone twice cesarean sections before, underwent open sigmoidectomy for sigmoid colon adenocarcinoma and received 12 cycles of FOLFOX regimen as adjuvant chemotherapy. Two years after sigmoidectomy, a follow-up CT scan revealed enlarged inguinal lymph nodes as well as growth of enhanced mass lesions on the abdominal wall at site of the cesarean section scar. Biopsy of both lesions revealed well-differentiated adenocarcinoma, and immunohistochemistry demonstrated positive expression of CDX2, substantiating its gastrointestinal origin. We therefore performed dissection of left inguinal lymph nodes and mass lesion of the abdominal wall. The patient died 51 months after lymph node dissection.ConclusionsThis is the first reported case of inguinal lymph node metastasis from colon cancer without invasion of the primary tumor to the abdominal wall or without involvement of the external iliac lymph nodes, suggesting that the pathway of inguinal metastasis originated from the abdominal wall metastasis. When inguinal lymph node metastasis from colon cancer is suspected, if an R0 resection was possible, inguinal lymph node dissection may be a potentially effective treatment.

Treatment of advanced gastrointestinal adenocarcinoma complicated with high-risk gastrointestinal stromal tumors (GISTs) in an elderly male patient: a case report and literature review

Currently, coexistence of gastrointestinal adenocarcinoma and gastrointestinal stromal tumors (GISTs) is still infrequent. What’s more, there are few guidelines for the drug therapy of both types of synchronous tumors. Here, we report such a dangerous case and review the related literature for a better treatment. A 79-year-old male patient was admitted to our hospital for abdominal pain and diarrhea more than a month and stopped relieve nature nine days. He was preliminarily diagnosed as sigmoid colon adenocarcinoma and GISTs after having a Computed Tomography scan at another hospital. After gastroscopy, colonoscopy and pathological examination, we further diagnosed synchronous advanced colorectal cancer (CRC) and high-risk GISTs. Through literature review and medical records, we carefully developed the treatment protocol for this case, which is the chemotherapy plan for gastrointestinal adenocarcinoma plus imatinib. There is still insufficient evidence on the safety and efficacy of the regimen and more research and trials are needed to evaluate it.

Gastrointestinal related symptoms on FOLFIRI regiments in resectable stage III colorectal cancer patients: A retrospective study

Introduction: Irinotecan is a second-line chemotherapy for colorectal carcinoma. The most frequent irinotecan toxicity is severe diarrhea and suppression of the immune system (neutropenia). Other side effects include nausea, hyperbilirubinemia, fatigue, emesis, fever, weight loss, alopecia, edema, dyspnoea and thromboembolism. Gastrointestinal related symptoms were the most common side effect following this chemotherapy regiment. Methods: This is a retrospective study which evaluated 10 patients with resectable stage III colorectal adeno carsinoma from January till December 2017, whose given adjuvant chemotherapy with FOLFIRI regiments. Data were taken from medical records during chemotherapy period for six months. Any gastrointestinal related symptoms during this period would be reported as Irrinotecan related side effects, and patients that could not completed the chemotherapy cycle will be excluded. Results: There were 10 patients included in this study, consisting of 6 male and 4 women. Patients age ranged from 32 to 65 years with an average of 51.6 years. Of the total patients, 5 patients had left sided colon adeno carcinoma, 3 patients with rectal carcinoma, 1 patient with sigmoid colon adenocarcinoma, and 1 patient with caecum carcinoma. All of the patients had post-chemotherapy complaints, such as nausea, vomiting, and diarrhea which could be tolerated well conservatively. 2 patients were excluded during this period because the symptoms can not be tolerated well and chemotherapy was interupted. Conclusion: Gastrointestinal related symptoms following FOLFIRI chemotherapy were common, the routine use as chemotherapy regiment should be evaluated later.

Acute Aortic Thrombosis Related to Adjuvant Capecitabine-Oxaliplatin in a Chinese Patient with Resected Adenocarcinoma of Sigmoid Colon

Aortic thrombosis is a rare disease entity which has been reported to be related to malignancy and chemotherapeutic agents. Here we present the first case in literature about a colon cancer patient with well-controlled vascular risk factors who developed acute aortic thrombosis after the first cycle of adjuvant chemotherapy with capecitabine-oxaliplatin. Risk factors and causal relationship between systemic anti-cancer agents and this condition are reviewed and discussed.

"Many shades of gray": a Case report on segment viii hepatic mass, metastatic or hcc?

Summary: We report a Case of a 55y/o male diagnosed with Sigmoid Colon Adenocarcinoma Stage II s/p Anterior Resection (2015) s/p Adjuvant Chemotherapy (up to January 2016). Patient was on surveillance work-up and noted a hepatic mass 2 years post-operatively. Nine months prior to admission, dynamic liver and lower abdomen CT scan was done and showed new ovoid solid hepatic mass exhibiting arterial enhancement and washout in the succeeding phases at segment VIII/dome of the right lobe; primary consideration is metastatic focus; primary hepatic neoplastic process is not ruled out. Eight months prior, F18-FDG PET/CT scan showed non-specific findings revealing a fairly defined, non-FDG-avid, enhancing mass (i.e. approximately 2.8cm x 3.1cm x 3.4cm, previously reported as 3.7 x 2.7cm) is again seen in Segment VIII of the normal-sized liver; an intense FDG uptake (SUV max upto 15.6) is seen in multiple normal-to-enlarged right axillary lymph nodes upto approximately 1.1cm in size probably metastatic.Patient underwent excision biopsy of right axillary lymph node and revealed chronic caseating granulomatous inflammation;given anti-TB treatment for 6mos.Subsequent imaging were done such as MRI,PET/CT Scan(F-18 FDG,C-11 Acetate) revealed mild accentuated C-acetate metabolism with ill-defined margins in segment VIII,not avid for FDG metabolism; Tc-99m sulphur colloid SPECT/CT with complete photopenia t/c FNH and a second one done with HCC as a consideration,and 4-phased dynamic Liver CT scan.Patient was then advised surgery and underwent Laparoscopic-assisted enterolysis,Segment VIII liver resection with ICG fluorescence.Final histopathology revealed 4.8cm hepatocellular carcinoma at segment VIII with parenchymal margins negative for tumor.Liver mass with a background of a primary malignancy may be a diagnostic dilemma.Optimal pre-operative imaging such as 4-phased dynamic liver CT scan or MRI, and an alternative imaging such as PET/CT scan or biopsy are options to aid the surgeon or hepatologist for planning of the succeeding treatment.

A Masquerading Mass: An Appendiceal Fecalith Posing as a Submucosal Lesion

Colonoscopy remains the gold standard for colon cancer prevention and surveillance. Colorectal cancer is one of the leading causes of cancer-related deaths in America. According to the CDC, 139,992 patients were diagnosed with colon cancer in 2014, making it the third most common cancer to affect both sexes. Routine colonoscopies oftentimes reveal unexpected findings. When this happens, it is important to keep an open mind when formulating a differential diagnosis. The following is the case of a routine surveillance colonoscopy highlighted by a finding, which ultimately unveiled an unexpected etiology. A 74-year-old Caucasian male with history of prostate cancer under surveillance, sigmoid colon adenocarcinoma (T3N0M0) s/p laparoscopic sigmoidectomy 8 years ago presented to our institution for a routine surveillance colonoscopy. His previous surveillance colonoscopies were negative. His routine labs were within normal limits. He denied any weight loss, abdominal pain, and displayed no symptoms consistent with GI bleeding. Our colonoscopy revealed 4 tubular adenomas (ranging from 5mm to 2cm in size), which were removed, and a hard, ulcerated nodular mass (2cm in diameter, seen in Figure 1) at the appendiceal orifice. The mass was biopsied extensively, however pathology was not diagnostic. Due to suspicion the mass was related to an underlying malignancy, we ordered a CEA and CT scans of the chest, abdomen, and pelvis. CEA was within normal limits, and imaging was significant for a 1.7cm soft tissue mass with central calcification (Figure 2). At that point, etiologies highest on our differential were carcinoid tumor, mucocele, and GIST. Our surgery colleagues proceeded with a laparoscopic appendectomy. Pathology of the removed tissue showed a markedly dilated appendiceal base with a luminal fecalith, and fibrous obliteration of the distal appendix. No malignancy was found and the etiology of the ulcerated submucosal lesion turned out to be an appendiceal fecalith. On our literature search, there are only a few reports of a fecalith presenting as a cecal submucosal mass. This case highlights the importance of maintaining a broad differential diagnosis when finding unexpected lesions during colonoscopy. In a patient such as this with a higher risk of cancer recurrence, malignancy is usually high on our differential. Even a colonic mass can have a unique and unexpected etiology such as an appendiceal fecalith.1662_A Figure 1. Colonoscopy images of the appendiceal mass1662_B Figure 2. CT imaging of the abdomen showing the 1.7 cm soft tissue mass with central calcification seen at the appendix

A left-sided cystic pancreatic incidentaloma with sigmoid colon adenocarcinoma: a case report

BackgroundThe synchronous colorectal malignancy is well described in the literature but combination of pancreatic incidentaloma with sigmoid cancer has not been well described and the association has not been described in syndrome.Case presentationA 65-year-old man from the Indian subcontinent with a history of abdominal pain with loss of appetite, and with a history of bleeding per rectum and altered bowel habits presented to our hospital. An abdominal examination revealed a palpable mass in the region of his epigastrium and left hypochondrium, and a rectal examination was normal. A work-up included blood investigations, an abdominal contrast-enhanced computed tomography scan, a colonoscopy, and a positron emission tomography/computed tomography scan. He was managed by simultaneous distal pancreaticosplenectomy and radical sigmoidectomy. The final histopathology results were suggestive of moderately differentiated adenocarcinoma of the sigmoid colon with serous cystadenoma of the pancreas.ConclusionsThe synchronous sigmoid colon cancer and pancreatic cystic incidentaloma is a rare presentation, which, to the best of our knowledge, has not been reported in the literature. We report the surgical management of this case and present a review of the literature. Genetic studies may be conducted to find out whether there is common genetic mutation resulting in these two malignancies, and may be helpful in screening programs.

Specimen processing and pathological evaluation of 113 samples of early colorectal cancer and precancerous lesion after endoscopic submucosal dissection

Objective To study the pathology and its significance of early colorectal cancer and precancerous lesions treated by endoscopic submucosal dissection (ESD). Methods A total of consecutive 113 cases were collected at the endoscopy center from August 2012 to June 2016, which were diagnosed as early colorectal cancer and precancerous lesions and undergone ESD. According to Japanese colorectal cancer treatment guidelines, specimens were processed and pathologically evaluated for histological type, tumor diameter, depth of invasion, budding grading, vessel invasion, and horizontal and vertical margin, as well as curative resection. Results There were 63 cases of adenoma (55.75%), including 29(25.66%) tubular adenoma, 2(1.77%) villous adenoma, and 32(28.32%) villioustublar adenoma. Thirty-four cases of serrated lesion were found, which included 19(16.81%) traditional serrated adenoma, 11(9.73%) sessile serrated adenoma, and 4(3.54%) hyperplasic polyp. There were also 16(14.16%) cases of early colorectal cancer with 7 cases of well-differentiated adenocarcinoma, 7 cases of moderately-differentiated adenocarcinoma, 1 case of poorly-differentiated adenocarcinoma, and 1 case of mucinous adenocarcinoma. Vessel invasion were observed in 2 of 16 cases of early colorectal cancer which were both moderately-differentiated adenocarcinoma in sigmoid colon. The vertical margins were negative in 108(95.58%) of 113 cases. Positive vertical margin were found in only 1 case (moderately-differentiated adenocarcinoma, pT1b2) and another case was suspected as positive. The rest 3 cases could not be precisely diagnosed. The horizontal margins were negative in 80(70.80%) of 113 cases and positive horizontal margin were found in 20(17.7%) cases (19 adenoma and 1 moderately-differentiated adenocarcinoma). Thirteen cases cannot be precisely diagnosed. Histologically, complete resection rate was 82.30%. The complete resection rate of invasive adenocarcinoma was 93.75%. Among 16 cases of invasive adenocarcinoma, 5 cases (curative rate: 31.25%) were judged as curative resection whereas 11 cases were considered as non-curative resection. Seven non-curative resection cases were treated with further surgery and did not relapse after the follow-up. Conclusion The standardized processing and precise histopathological evaluation are key factors for colorectal ESD technique, which play an important role in the success of endoscopic therapy. Key words: Colorectal neoplasms; Early diagnosis; Pathology, clinical; Endoscopic submucosal dissection