Metachronous colorectal cancer: A competing risks analysis with consideration for a stratified approach to surveillance colonoscopy

Risk factors for metachronous colorectal cancer and advanced neoplasia following primary colorectal cancer: a systematic review and meta-analysis

BACKGROUND

Identifying risk factors for metachronous colorectal cancer (CRC) and metachronous advanced neoplasia could be useful for guiding surveillance. We conducted a systematic review and meta-analysis to investigate risk factors for metachronous CRC and advanced neoplasia.

METHODS

Searches were conducted in MEDLINE, Embase, Web of Science and Cochrane Central Registry of Controlled Trials for articles (searching period: 1945 to Feburary, 2021) that reported the results of an association between any factor and metachronous advanced neoplasia or metachronous CRC. There were no restrictions on the publication date or language. Random effects models were fitted to estimate the combined association between the risk factors and metachronous CRC or advanced neoplasia. The Risk of Bias In Non-Randomised Studies of Interventions tool (ROBINS-I) was used to assess the risk of bias of included studies.

RESULTS

In total, 22 observational studies with 625,208 participants were included in the systematic review and meta-analysis. Of these, 13 studies investigated risk factors for metachronous CRC and 9 for advanced neoplasia. The risks of metachronous CRC or advanced neoplasia were higher if the first CRC was diagnosed in the presence of a synchronous advanced lesion (pooled risk ratio (RR) from 3 studies: 3.61, 95% confidence interval (CI): 1.44-9.05; and pooled RR from 8 studies: 2.77, 95% CI: 2.23-3.43, respectively). The risk of metachronous CRC was lower, but the risk of metachronous advanced neoplasia was higher if the first CRC was distal (compared with proximal) (pooled RR from 3 studies: 0.48, 95% CI: 0.23-0.98; and pooled RR from 2 studies: 2.99, 95% CI: 1.60-5.58 respectively). The risk of metachronous advanced neoplasia increased with age (pooled RR from 3 studies: 1.07 per year of age, 95% CI: 1.03-1.11). There was no evidence that any lifestyle risk factors studied were associated with the risk of metachronous CRC or advanced neoplasia.

CONCLUSIONS

The identified risk factors for metachronous CRC and advanced neoplasia might be useful to tailor the existing surveillance guidelines after the first CRC. There were potential limitations due to possible misclassification of the outcome, confounding and risk of bias, and the findings cannot be generalised to high-risk genetic syndrome cases.

New and Recurrent Colorectal Cancers After Resection: a Systematic Review and Meta-analysis of Endoscopic Surveillance Studies

BACKGROUND & AIMS

Outcomes of endoscopic surveillance after surgery for colorectal cancer (CRC) vary with the incidence and timing of CRC detection at anastomoses or non-anastomoses in the colorectum. We performed a systematic review and meta-analysis to evaluate the incidence of CRCs identified during surveillance colonoscopies of patients who have already undergone surgery for this cancer.

METHODS

We searched PubMed, EMBASE, SCOPUS, and the Cochrane Central Register of Clinical Trials through January 1, 2018 to identify studies investigating rates of CRCs at anastomoses or other locations in the colorectum after curative surgery for primary CRC. We collected data from published randomized controlled, prospective, and retrospective cohort studies. Data were analyzed by multivariate meta-analytic models.

RESULTS

From 2373 citations, we selected 27 studies with data on 15,803 index CRCs for analysis (89% of patients with stage I-III CRC). Overall, 296 CRCs at non-anastomotic locations were reported over time periods of more than 16 years (cumulative incidence, 2.2% of CRCs; 95% confidence interval [CI], 1.8%-2.9%). The risk of CRC at a non-anastomotic location was significantly reduced more than 36 months after resection compared with before this time point (odds ratio for non-anastomotic CRCs at 36-48 months vs 6-12 months after surgery, 0.61; 95% CI, 0.37-0.98; P = .031); 53.7% of all non-anastomotic CRCs were detected within 36 months of surgery. One hundred and fifty-eight CRCs were detected at anastomoses (cumulative incidence of 2.7%; 95% CI, 1.9%-3.9%). The risk of CRCs at anastomoses was significantly lower 24 months after resection than before (odds ratio for CRCs at anastomoses at 25-36 months after surgery vs 6-12 months, 0.56; 95% CI, 0.32-0.98; P = .036); 90.8% of all CRCs at anastomoses were detected within 36 months of surgery.

CONCLUSIONS

After surgery for CRC, the highest risk of CRCs at anastomoses and at other locations in the colorectum is highest during 36 months after surgery-risk decreases thereafter. Patients who have undergone CRC resection should be evaluated by colonoscopy more closely during this time period. Longer intervals may be considered thereafter.

Vascular anatomy of the transverse mesocolon and bidirectional laparoscopic D3 lymph node dissection for patients with advanced transverse colon cancer

Laparoscopic D3 lymph node dissection for transverse colon cancer is technically demanding because of complicated anatomy. Here, we reviewed the vascular structure of the transverse mesocolon, explored the extent of the base of the transverse mesocolon, and evaluated the feasibility and oncological safety of D3 lymph node dissection. We retrospectively reviewed the clinical records of 42 patients with advanced transverse colon cancer who underwent curative surgery and D3 dissection at Kyushu University Hospital between January 2008 and December 2015. We examined the venous and arterial anatomy of the transverse mesocolon of each resection and compared surgical outcomes between patients who underwent laparoscopic D3 (Lap D3) and open D3 (Open D3) dissection. Patients included two with Stage I, 18 with Stage II, 20 with Stage III, and two with Stage IVA. Thirty-six (85.7%) and six (14.3%) patients underwent Lap D3 or Open D3, respectively. The tumor sizes of the Open D3 and Lap D3 groups were 7.8 and 3.7 cm, respectively (P < 0.001). The Lap D3 group had significantly less blood loss (26 mL vs 272 mL, P = 0.002). The other outcomes of the two groups were not significantly different, including 3-year overall survival (87.7% vs 83.3%, P = 0.385). We observed four patterns of the middle colic artery (MCA) arising from the superior mesenteric artery (SMA), and the frequency of occurrence of a single MCA was 64.3%. The right-middle colic vein (MCV) was present in 92.9% of resections and served as a tributary of the gastrocolic trunk, and 90.5% of the left MCVs drained into the superior mesenteric vein (SMV). The root of the transverse mesocolon was broadly attached to the head of the pancreas and to the surfaces of the SMV and SMA. Laparoscopic D3 lymph node dissection may be tolerated by patients with advanced transverse colon cancer.

Risk of Synchronous and Metachronous Colorectal Cancer: Population-Based Estimates in Denmark with Focus on Non-Hereditary Cases Diagnosed After Age 50

BACKGROUND AND AIMS

The risk of synchronous and metachronous colorectal cancer is influenced by heritable and environmental factors. As a basis for comparative studies, we provide population-based estimates of synchronous and metachronous colorectal cancer with a focus on non-heritable cases.

MATERIAL AND METHODS

Based on data from national Danish cancer registers, we estimated the proportion of synchronous colorectal cancer and the incidence rates and risks for metachronous colorectal cancer in 28,504 individuals, who developed 577 metachronous colorectal cancer above age 50.

RESULTS

Synchronous colorectal cancer was diagnosed in 1.3% of the cases. The risk of metachronous colorectal cancer was associated with sex, tumor location, and age with the strongest influence from the latter. The incidence rate ratios for metachronous colorectal cancer ranged from above 6 in patients below age 65 to <1-3.2 in patients above age 65. The absolute risk of metachronous colorectal cancer was ⩾10% in patients below age 65 and 1.0%-8.0% in patients above age 65.

CONCLUSION

Individuals who develop sporadic, non-inherited colorectal cancer above age 50 are at a significantly increased risk of metachronous colorectal cancer with risk estimates that are strongly affected by age. This observation underscores the need for development of targeted surveillance in the most common clinical subset of colorectal cancer.

Various clinicopathological features of patients with metachronous colorectal cancer in relation to different diagnostic intervals

BACKGROUNDS

Clinicopathologic factors relating to developing metachronous colorectal cancer (CRC) have been reported. However, the effects of different diagnostic intervals on these risk factors required further analysis.

PATIENTS AND METHODS

This retrospective study comprised 14,481 patients diagnosed from January 1995 to December 2012. Metachronous CRC was defined as the occurrence of a second colorectal cancer at least 1 year post-operatively.

RESULTS

A total of 153 (1.06%) patients developed metachronous CRCs during the follow-up. Significantly higher rates of developing metachronous cancer occurred in male patients (1.2 vs 0.9%), patients with synchronous CRC (2.0 vs 1.0%), and patients with a positive family history of CRC (1.4 vs 0.9%). Pertaining to diagnostic intervals related to clinicopathological features, more severe staging was significant in the diagnostic interval between 2 and 3 years (35 vs 7.7%, 20.6%, 17.5%, P = .01) compared with other intervals. Male patients were more frequently detected to have CRC within 3 years compared with females (53.1 vs 29.1%, P = .005). For a diagnostic interval ≧ 5 years, a significantly higher rate of metachronous CRC located at the right colon was observed than that located at the left colon (36.6 vs 19.7%, p = 0.03).

CONCLUSIONS

We evinced that a diagnostic interval between 2 and 3 years was a key time for metachronous CRC diagnosis with worse staging distribution. Based on current findings, we recommend the stratification of metachronous CRCs into diagnostic intervals of 1-2, 2-3, and ≧ 3 years, as they exhibit significantly different characteristics.

Challenging a dogma: five-year survival does not equal cure in all colorectal cancer patients

BACKGROUND

The current study tried to evaluate the factors affecting 10- to 20- years' survival among long term survivors (>5 years) of colorectal cancer (CRC).

METHODS

Surveillance, Epidemiology and End Results (SEER) database (1988-2008) was queried through SEER*Stat program.Univariate probability of overall and cancer-specific survival was determined and the difference between groups was examined. Multivariate analysis for factors affecting overall and cancer-specific survival was also conducted.

RESULTS

Among node positive patients (Dukes C), 34% of the deaths beyond 5 years can be attributed to CRC; while among M1 patients, 63% of the deaths beyond 5 years can be attributed to CRC. The following factors were predictors of better overall survival in multivariate analysis: younger age, white race (versus black race), female gender, Right colon location (versus rectal location), earlier stage and surgery (P <0.0001 for all parameters). Similarly, the following factors were predictors of better cancer-specific survival in multivariate analysis: younger age, white race (versus black race), female gender, Right colon location (versus left colon and rectal locations), earlier stage and surgery (P <0.0001 for all parameters).

CONCLUSION

Among node positive long-term CRC survivors, more than one third of all deaths can be attributed to CRC.

Incidence and predictors of adenoma after surgery for colorectal cancer

OBJECTIVE

Patients with colorectal cancer (CRC) are at increased risk for developing metachronous premalignant and malignant lesions. However, its real incidence and underlying risk factors are still unclear, and therefore quality measures for colonoscopy under this indication have not been completely established. The aim of this study was to assess the incidence of and risk factors for the development of adenomas after surgery for CRC.

PATIENTS AND METHODS

A total of 535 patients submitted to curative surgery for CRC between January 2008 and December 2011 were selected and their clinical records and surveillance colonoscopies were reviewed.

RESULTS

During a median follow-up of 62 months, 39.4% of the patients developed adenomas, 17.6% advanced adenomas and 3.4% developed metachronous cancers. Male sex [adjusted odds ratio (AOR)=1.99; 95% confidence interval (CI): 1.29-3.07] was an independent risk factor for adenomas during follow-up and absence of a high-quality baseline colonoscopy was the only independent risk factor for advanced adenomas (AOR=1.78; 95% CI: 1.03-3.07) and metachronous cancer (AOR=7.05; 95% CI: 1.52-32.66). In patients who had undergone a high-quality colonoscopy at baseline and at the first follow-up, the presence of adenomas (odds ratio=12.30; 95% CI: 2.30-66.25) and advanced adenomas (odds ratio=10.50; 95% CI: 2.20-50.18) in the first follow-up colonoscopy was a risk factor for the development of metachronous advanced adenomas during the subsequent surveillance.

CONCLUSION

Undergoing a high-quality baseline colonoscopy is the most important factor for reducing the incidence of advanced lesions after CRC surgery. All patients remain at high-risk for adenomas and advanced adenomas, but standardized follow-up should be adjusted after the first year of follow-up.

Surveillance after endoscopic and surgical resection of colorectal cancer

With the increase in colorectal cancer burden, surveillance following endoscopic and surgical resection is an essential issue. The aim of surveillance programs is improvement of patient survival by early detection of residual tumor tissue or local recurrence, metachronous colorectal tumors, and metastases. Appropriate surveillance should be determined according to this risk of factors. In current guidelines, only surveillance colonoscopy is recommended after endoscopic resection of polyps with high-grade dysplasia, whereas intensive, multimodality surveillance using colonoscopy, radiological imaging and tumor marker measurements is recommended following surgical resection of invasive colorectal cancer. Detailed recommendations, including the timing of surveillance, are described based on high-quality evidence. However, there are still many unresolved issues for which more high-quality evidence is required.

Colonoscopy Surveillance After Colorectal Cancer Resection: Recommendations of the US Multi-Society Task Force on Colorectal Cancer

The US Multi-Society Task Force has developed updated recommendations to guide health care providers with the surveillance of patients after colorectal cancer (CRC) resection with curative intent. This document is based on a critical review of the literature regarding the role of colonoscopy, flexible sigmoidoscopy, endoscopic ultrasound, fecal testing and CT colonography in this setting. The document addresses the effect of surveillance, with focus on colonoscopy, on patient survival after CRC resection, the appropriate use and timing of colonoscopy for perioperative clearing and for postoperative prevention of metachronous CRC, specific considerations for the detection of local recurrence in the case of rectal cancer, as well as the place of CT colonography and fecal tests in post-CRC surveillance.

Colonoscopy Surveillance after Colorectal Cancer Resection: Recommendations of the US Multi-Society Task Force on Colorectal Cancer

The US Multi-Society Task Force has developed updated recommendations to guide health care providers with the surveillance of patients after colorectal cancer (CRC) resection with curative intent. This document is based on a critical review of the literature regarding the role of colonoscopy, flexible sigmoidoscopy, endoscopic ultrasound, fecal testing and CT colonography in this setting. The document addresses the effect of surveillance, with focus on colonoscopy, on patient survival after CRC resection, the appropriate use and timing of colonoscopy for perioperative clearing and for postoperative prevention of metachronous CRC, specific considerations for the detection of local recurrence in the case of rectal cancer, as well as the place of CT colonography and fecal tests in post-CRC surveillance.

Endoscopic follow-up after surgery for colorectal cancer

OBJECTIVE

Follow-up surgery for colorectal cancer is recommended. The yield of endoscopy is unknown and was therefore studied.

METHODS

Patients with colorectal cancer in the years 2003, 2004 and 2005 were included. Evaluation was done in July 2014.

RESULTS

Cancer was diagnosed in 267 patients. These were divided into three groups: group 1-still alive (n = 88), group 2-died within 1 year after diagnosis (n = 67), and group 3-died more than 1 year after diagnosis (n = 112). Patients in group 3 showed a trend towards non-cancer-related death (p = 0.06). Endoscopic follow-up was done in 101 patients (37.6 %). Patients still alive underwent more often follow-up colonoscopy (p < 0.001). Patients still alive had more often synchronous polyps detected during index endoscopy compared with patients of groups 2 and 3 (p = 0.03). Follow-up revealed more often new polyp(s) (p = 0.006). If no polyps were seen during the time of diagnosing cancer, follow-up endoscopy detected polyp(s) in 26 % of cases. Two newly developed cancers in group 1 and three in group 3 were diagnosed.

CONCLUSION

Endoscopic follow-up after curative surgery for colorectal cancer has a high diagnostic yield. Whether detection and removal of polyps increases survival is not yet clear.

Higher adenoma recurrence rate after left- versus right-sided colectomy for colon cancer

BACKGROUND

Patients with history of colonic resection for cancer have an increased risk of the development of metachronous malignant and premalignant lesions. Scanty data are reported on detection rates of premalignant lesions during colonoscopy surveillance in this setting.

OBJECTIVE

To assess the risk of metachronous precancerous lesions developing in patients with previous colonic surgery for cancer according to the resection type.

DESIGN

Retrospective study.

SETTING

Two academic centers in Italy.

PATIENTS

A total of 441 patients; 256 with previous left-sided colectomy (LCR) (LCR group) and 185 with previous right-sided colectomy (RCR) (RCR group).

INTERVENTIONS

Second surveillance colonoscopy.

MAIN OUTCOME MEASUREMENTS

Polyp and adenoma detection rates.

RESULTS

At least 1 adenoma was diagnosed in 76 of 256 patients (30% adenoma detection rate) and in 35 of 185 patients (19% adenoma detection rate) in the LCR and RCR groups, respectively (P=.014), yielding an odds ratio of 1.83 (95% confidence interval, 1.16-2.89). Corresponding figures for the polyp detection rate were 39% and 25%, respectively (P=.002; odds ratio 1.97; 95% confidence interval, 1.30-3.00).

LIMITATIONS

Retrospective study with colonoscopy baseline information missing.

CONCLUSIONS

Patients who have undergone LCR are at higher risk of the development of adenomas than those who have undergone RCR. If this result is confirmed by large prospective studies, surveillance programs could be targeted according to the type of colonic resection, with longer intervals for patients with previous RCR compared with LCR.

Metachronous colorectal cancers result from missed lesions and non-compliance with surveillance

BACKGROUND

Several studies examined the rate of colorectal cancer (CRC) developed during colonoscopy surveillance after CRC resection (ie, metachronous CRC [mCRC]), yet the underlying etiology is unclear.

OBJECTIVE

To examine the rate and likely etiology of mCRCs.

DESIGN

Population-based, multicenter study. Review of clinical and histopathologic records, including data of the national pathology database and The Netherlands Cancer Registry.

SETTING

National cancer databases reviewed at 3 hospitals in South-Limburg, The Netherlands.

PATIENTS

Total CRC population diagnosed in South-Limburg from January 2001 to December 2010.

INTERVENTIONS

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

We defined an mCRC as a second primary CRC, diagnosed >6 months after the primary CRC. By using a modified algorithm to ascribe likely etiology, we classified the mCRCs into cancers caused by non-compliance with surveillance recommendations, inadequate examination, incomplete resection of precursor lesions (CRC in same segment as previous advanced adenoma), missed lesions, or newly developed cancers.

RESULTS

We included a total of 5157 patients with CRC, of whom 93 (1.8%) had mCRCs, which were diagnosed on an average of 81 months (range 7-356 months) after the initial CRC diagnosis. Of all mCRCs, 43.0% were attributable to non-compliance with surveillance advice, 43.0% to missed lesions, 5.4% to incompletely resected lesions, 5.4% to newly developed cancers, and 3.2% to inadequate examination. Age-adjusted and sex-adjusted logistic regression analyses showed that mCRCs were significantly smaller in size (odds ratio [OR] 0.8; 95% confidence interval [CI], 0.7-0.9) and more often poorly differentiated (OR 1.7; 95% CI, 1.0-2.8) than were solitary CRCs.

LIMITATIONS

Retrospective evaluation of clinical data.

CONCLUSION

In this study, 1.8% of all patients with CRC developed mCRCs, and the vast majority were attributable to missed lesions or non-compliance with surveillance advice. Our findings underscore the importance of high-quality colonoscopy to maximize the benefit of post-CRC surveillance.