Prognostic Impact of Primary Tumor Sidedness in Stage III Colorectal Cancer: Real-World Evidence from a Brazilian Cohort

BACKGROUND

Primary tumor sidedness (PTS) is an independent prognostic factor in patients with metastatic colorectal cancer (CRC), with a worse prognosis for right-sided tumors. There are limited data on the prognostic impact of PTS in stage III CRC. The main objective of this study was to analyze the prognostic impact of PTS in stage III CRC.

PATIENTS AND METHODS

A retrospective and uni-institutional cohort study was performed in an oncology reference center. Patients with stage III CRC treated with a 5-fluorouracil and oxaliplatin-based chemotherapy regimen (mFLOX regimen) from October 2007 to February 2013 were included. The primary outcome was the probability of overall survival (OS) at 5 years stratified by PTS. Secondary outcomes were the probability of disease-free survival (DFS) at 5 years and an analysis of the prognostic impact of clinical and molecular biomarkers. Kaplan‒Meier curves were used, and Cox models were used to evaluate prognostic factors associated with OS and DFS.

RESULTS

Overall, 265 patients were evaluated. Transverse colon tumors, multicentric tumors, and undetermined primary subsites were excluded, resulting in 234 patients classified according to PTS: 95 with right sidedness (40.6%) and 139 with left sidedness (59.4%). The median follow-up time was 66 months [interquartile range (IQR): 39-81]. The 5-year OS probabilities for right-sided and left-sided tumors were 67% (95% CI: 58%-77%) and 82% (75%-89%), respectively [hazard ratio (HR): 2.02, 95% CI: 1.18-3.46; P = .010]. The 5-year probabilities of DFS for right-sided and left-sided tumors were 58% (49%-69%) and 65% (58%-74%), respectively (HR: 1.29, 0.84-1.97; P = 0.248).

CONCLUSION

These data suggest that there may be a worse prognosis (inferior OS at 5 years) for resected right-sided stage III CRC patients treated in the real world. However, these data need to be confirmed by prospective studies with a larger number of participants.

Extensively infarcted giant solitary hamartomatous polyp treated with endoscopic full-thickness resection: A case report

BACKGROUND

Solitary hamartomatous polyps (SHPs) are rare lesions. Endoscopic full-thickness resection (EFTR) is a highly efficient and minimally invasive endoscopic procedure that benefits from complete lesion removal and high safety.

CASE SUMMARY

A 47-year-old man was admitted to our hospital after experiencing hypogastric pain and constipation for over fifteen days. Computed tomography and endoscopy revealed a giant pedunculated polyp (approximately 18 cm long) in the descending and sigmoid colon. This is the largest SHP reported to date. Having considered the condition of the patient and mass growth, the polyp was removed using EFTR.

CONCLUSION

On the basis of clinical and pathological evaluations, the mass was considered an SHP.

Vascular variations encountered during laparoscopic surgery for transverse colon, splenic flexure, and descending colon cancer: a retrospective cohort study

BACKGROUND

Laparoscopic surgery for cancer located in the transverse colon or splenic flexure is difficult because of vascular variability in this region and adjacent vital organs such as the pancreas, spleen, and duodenum.

METHODS

This retrospective cohort study involved 51 patients who underwent laparoscopic surgery for colon cancer at Tokushima University Hospital from July 2015 to December 2020. Variations of the middle colic artery (MCA), left colic artery (LCA), middle colic vein (MCV), and first jejunal vein (FJV) and short-term outcomes of laparoscopic surgery in patients with each vascular variation were evaluated.

RESULTS

Variations of the MCA, LCA, MCV, and FJV were classified into four, three, five, and three patterns, respectively. The short-term outcomes of laparoscopic surgery for transverse colon cancer in patients with MCA variations and those with FJV variations were evaluated, and no significant difference was found in the operation time, blood loss, postoperative complication rate, time from surgery to start of dietary intake, or time from surgery to discharge among the different variations. Additionally, no significant differences were found in the short-term outcomes of laparoscopic surgery for descending colon cancer in patients with LCA variations.

CONCLUSION

Preoperative assessment of vascular variations may contribute to the stability of short-term outcomes of laparoscopic surgery for transverse colon, splenic flexure, and descending colon cancer.

The oncologic safety of left colectomy with modified complete mesocolic excision for distal transverse colon cancer: Comparison with descending colon cancer

BACKGROUND

The optimal surgical approach for distal transverse colon cancer has not been well established. This study aimed to evaluate the oncologic safety of left colectomy with a modified complete mesocolic excision for distal transverse colon cancer as compared with descending colon cancer.

MATERIAL AND METHODS

This study involved 383 patients who underwent left colectomy with modified complete mesocolic excision for non-metastatic distal transverse and splenic flexure colon (transverse group, N = 110) and descending colon cancer (descending group, N = 237) from 3 institutions. Recurrence-free survival (RFS) and overall survival (OS) were compared between the two groups.

RESULTS

Baseline characteristics between the two groups were similar except for the length of the distal margin (transverse group = 11.0 cm vs descending group = 9.0 cm, p = 0.004). During a median follow-up of 47.0 months, RFS and OS were not different between the transverse and descending groups (5-year RFS: 82% vs 71%, p = 0.139; 5-year OS: 83% vs 79%, p = 0.416, respectively). In multivariable analysis, RFS and OS were not different between the two groups (transverse group vs. descending group: adjusted hazard ratio [aHR] = 1.557, 95% CI = 0.786-3.084, p = 0.204; aHR = 1.251, 95% CI = 0.530-2.952, p = 0.609).

CONCLUSION

The oncologic outcomes of left colectomy with a modified complete mesocolic excision of distal transverse colon cancer were comparable to those of descending colon cancer. Left colectomy with a modified complete mesocolic excision can be an acceptable surgical treatment for distal transverse colon cancer.

Congenital positional anomaly of descending colon and sigmoid colon: Its embryological basis and clinical implications

The rotation of the midgut is essential for normal placement of intestines in the abdominal cavity. The process of midgut rotation and simultaneous retraction of the herniated intestinal loops pushes the hind gut to the left side of the abdominal cavity. So the descending colon and the sigmoid colon occupy the left side of the abdominal cavity. In this report, we document a male cadaver that revealed right-sided sigmoid colon. On further dissection, the descending colon was found lying in the midline with a small peritoneal fold stretching from the right side of sigmoid colon to ileocecal junction. There was also variation in the inferior mesenteric artery supplying the displaced descending colon and sigmoid colon. The possible embryological and molecular basis of this variation has been discussed. The anatomical knowledge of this variation is essential for interventional and diagnostic colonoscopy procedures and colonic surgeries.

Large cell neuroendocrine carcinoma in the unusual location of the descending colon

Neuroendocrine neoplasms are most often found in the small intestine, rectum, appendix, and stomach. The colon, excluding the appendix and the cecum, is a rare location for these neoplasms and often gives rise to highly proliferative, poorly differentiated tumors with aggressive features and dismal prognosis. A 32-year-old male presents with a large cell neuroendocrine carcinoma arising from an unusual location, the descending colon. The patient's clinical and imaging characteristics resembles those seen in the much more common neoplasm, colonic adenocarcinoma. Computed tomography and In-111 octreotide scan are limited in diagnosing large cell neuroendocrine carcinoma. Pathologic correlation of a surgical specimen is required to make the correct diagnosis.

Female Sex and Right-Sided Tumor Location Are Poor Prognostic Factors for Patients With Stage III Colon Cancer After a Curative Resection

Purpose

Stage-IIIC colon cancer is an advanced disease; however, its oncologic outcomes and prognostic factors remain unclear. In this study, we aimed to determine the predictors of disease-free survival (DFS) in patients with stage-IIIC colon cancer.

Methods

From a multicenter database, we retrospectively enrolled 611 patients (355 men and 256 women) who had undergone a potentially curative resection for a stage-IIIC colon adenocarcinoma between 2003 and 2011. The primary end-point was the 5-year DFS.

Results

The median age was 62 years; 213 and 398 patients had right-sided colon cancer (RCC) and left-sided colon cancer (LCC), respectively. The 5-year DFS in all patients was 52.0%; median follow-up time was 35 months (range, 1–134 months). A multivariate Cox regression revealed that female sex (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.19–1.90; P < 0.01), right-sided tumor location (HR, 1.65; 95% CI, 1.29–2.11; P < 0.01), lymphatic invasion (HR, 1.52; 95% CI, 1.08–2.15; P < 0.01) and a high (≥0.4) metastatic lymph node ratio (HR, 3.72; 95% CI, 2.63–5.24; P < 0.01) were independent predictors of worse 5-year DFS. Female patients with RCC were 1.79 fold more likely to experience recurrence than male patients with LCC.

Conclusion

Female sex and right-sided tumor location are associated with higher tumor recurrence rates in patients with stage-IIIC colon cancers. Aggressive treatment and close surveillance should be planned for patients in these groups.

Right colonic diverticulitis in Caucasians: presentation and outcomes versus left-sided disease

PURPOSE

To compare clinical features, computed tomography (CT) findings, and outcomes of right vs. left colonic diverticulitis (CD) in Caucasians.

METHODS

This single-center retrospective case-control study of patients seen between July 2005 and February 2013 included 30 consecutive cases of right CD and 70 controls taken at random from a consecutive cohort of patients with left CD. The final diagnosis was established by consensus between a gastrointestinal surgeon and a gastrointestinal radiologist. Clinical features, treatment, and follow-up data were collected. Two radiologists blinded to patient data reached a consensus about multiple CT criteria. Cases and controls were compared using appropriate statistical tests, and odds ratios (ORs) associated with clinically meaningful variables were computed using univariate logistic regression.

RESULTS

Median age was significantly lower in cases than in controls (48.5 years [IQR, 31-61] vs. 63.5 years [54-75], P < 0.0001). A body mass index <20 kg/m² compared to >30 kg/m² was associated with a higher risk of right than of left CD (OR 22.7, 95% confidence interval [95% CI], 2.6-200, P = 0.005). Compared to controls, cases more often had CT evidence of focal diverticular inflammation (86.7% [26/30] vs. 50% [35/70], P = 0.0006) and noncircumferential (≤180°) colonic wall thickening (66.7% [20/30] vs. 20% [14/70], P < 0.001). Complications were less common in the cases (6.7% [2/30] vs. 25.7% [18/70] than in controls, P = 0.03).

CONCLUSION

In Caucasians, right CD occurs in younger and thinner patients and carries a lower risk of complications compared to left CD. Focal diverticular inflammation by CT is more common in right than in left CD.

Colonic intussusception in descending colon: An unusual presentation of colon lipoma

Lipomas of the colon are relatively rare benign soft tissue tumors derived from mature adipocytes of mesenchymatic origin. During colonoscopy, surgery or autopsy they are generally discovered incidentally. Most cases are asymptomatic, with a small tumor size, and do not need any special treatment. However, in the cases with larger in size of tumor some symptoms such as anemia, abdominal pain, constipation, diarrhea, bleeding, or intussusception may be presented. We reported a 47-year-old woman with colonic intussusception in the descending colon caused by colonic lipoma and diagnosed after surgical exploration for obstructive colonic mass.

Case Report of the Descending Colon Located Completely in the Right Extraperitoneal Cavity and Sigmoid Colon Located in the Right Quadrant in a Patient with a Splenic Flexure Tumor: a Rare Anomaly

Cases in which congenital anomalies of the colon and colon tumors are observed together are very rare. The aim of this article is to present a splenic flexure tumor case, which possessed the anomaly of the descending colon in the right extraperitoneal space and the sigmoid colon located in the right quadrant. Similar findings have previously been reported in two cases in cadaveric studies.

Right sided descending and sigmoid colon: its embryological basis and clinical implications

Anatomical variations of the colon are described by various authors, but the occurrence of right sided descending and sigmoid colon is rare and has not been reported. We found that the anomalous right-sided descending and sigmoid colon had four parts. The proximal segment of the first part consisted of the descending colon extending across the midline from the splenic flexure to the portion supplied by the left colic artery. The distal segment was supplied by the superior sigmoid artery. The second and third parts formed a loop in the right lumbar region anterior to the lumbar cecum. The fourth part was in the lesser pelvis, extending from right sacroiliac joint to the third sacral body. Parts two, three, and four were supplied by the inferior sigmoid artery, which arose from the right side of the inferior mesenteric artery. The ascending and transverse colon was normally placed. This is a rare anomaly that has not been reported so far in adults and is of immense importance to interventional radiologists and colorectal surgeons. The embryological basis of such an anomaly is defective fixation occurring as early as the 12th-17th week of intrauterine life.

[Anatomical radiology of the descending colon in the left pararenal space: about 1084 cases]

AIMS

Due to the severity of colonic injuries and their frequency on the left side, we study relationships between the left kidney and the descending colon to identify subjects at risk of colonic perforation during percutaneous surgery of the left kidney.

MATERIAL AND METHODS

Over a period of 3 years we exploited abdominal CT scans for 1084 patients in both sexes without any visceral or parietal lesions. We studied the situation and relationships of the lumbar part of the descending colon in the left pararenal space using a conventional grid technique.

RESULTS

The preferential site of the colon in both sexes was laterorenal in 55.8% of cases. We also found the descending colon in a posterolateral situation in 21.1% of cases, and in an anterolateral situation in 14.8% of cases. In women, the posterolateral situation was twice more common than in men, but we did not observe any post-renal situation. Laterorenal and posterolateral situations were the most frequent in patients less than 50 years; while beyond this age 70.1% of subjects had a laterorenal type.

CONCLUSION

Sex and age affect topographic variations of the lumbar part of the descending colon in the left pararenal space. Although they are rare or aberrant, some locations exist and should not be ignored by the operator. These locations are risk factors of colonic lesion during percutaneous approach of the left kidney.

A stercoral perforation of the descending colon

This is a case report on a stercoral perforation of the descending colon that was not adequately treated in the first operation. Re-operation was required in order to revise the primary repair site and to remove the impacted fecaloma.

Diagnosis and treatment of primary malignant melanoma in the descending colon: a report of one case

Malignant melanoma arises from melanocytes. As blood or lymph node metastasis occurs in the early stage of malignant melanoma, the disease has a poor prognosis. The anorectum, behind the skin and eyes, is the third most frequent site of malignant melanoma. Primary malignant melanoma of the colon is a rare clinical condition. Here, we report a case of primary malignant melanoma in the colon in a 66-year-old female. She was definitely diagnosed as primary malignant melanoma in the descending colon after radical resection and lymph node dissection. Postoperative systemic chemotherapy and immunotherapy achieved good effects. The patient is still alive five years postoperatively.