Predictive factors for detecting colorectal carcinomas in surveillance colonoscopy after colorectal cancer surgery

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.

Is frequent measurement of tumor markers beneficial for postoperative surveillance of colorectal cancer?

PURPOSE

To determine whether frequent measurement of tumor markers triggers early detection of colorectal cancer recurrence.

METHODS

Of 1,651 consecutive patients undergoing colorectal cancer surgery between 2010 and 2016, 1,050 were included. CEA and CA 19-9 were considered to be postoperative tumor markers and were measured every 3 months for 3 years, and then every 6 months for 2 years. Sensitivity analysis of elevated CEA and CA19-9 levels and multivariate analysis of factors associated with elevated CEA and CA19-9 levels were performed. The proportion of triggers for detecting recurrence was determined.

RESULTS

The median follow-up period was 5.3 years. After applying the exclusion criteria, 1,050 patients were analyzed, 176 (16.8%) of whom were found to have recurrence. After excluding patients with persistently elevated CEA and CA19-9 levels before and after surgery from the 176 patients, 71 (43.6%) of 163 patients had elevated CEA levels and 35 (20.2%) of 173 patients had elevated CA19-9 levels. Sensitivity/positive predictive values for elevated CEA and CA19-9 levels at recurrence were 43.6%/32.3% and 20.2%/32.4%, respectively. Lymph node metastasis was a factor associated with both elevated CEA and CA19-9 levels at recurrence. Of the 176 patients, computed tomography triggered the detection of recurrence in 137 (78%) and elevated tumor marker levels in 13 (7%); the diagnostic lead interval in the latter 13 patients was 1.7 months.

CONCLUSION

Tumor marker measurements in surveillance after radical colorectal cancer resection contribute little to early detection, and frequent measurements are unnecessary for stage I patients with low risk of recurrence.

The necessity of intensive surveillance colonoscopy for patients with a remaining right colon after resection of colorectal cancer: a retrospective cohort study

PURPOSE

To clarify how often postoperative surveillance colonoscopy should be undertaken based on the risk factors for the development of metachronous cancer (MC) and advanced adenoma (AA) after surgery for colorectal cancer.

METHODS

We collected data of consecutive patients who underwent curative resection for primary colorectal cancer between 2005 and 2012, with preoperative colonoscopy and surveillance colonoscopy at 1 year after surgery (406 patients, mean age: 69 years, 59% male). The detection rates of AA (with villous features, > 10 mm or high-grade dysplasia) and MC by surveillance colonoscopy were the primary outcomes.

RESULTS

At 5 years, colonoscopy was performed as postoperative surveillance an average of 3.2 times. AA and MC were detected in 57 (14.0%) and 18 patients (4.4%), respectively. Both lesions were more common in the right colon (n = 43) than in the left colon (n = 28). The detection rate did not differ to a statistically significant extent according to the number of colonoscopies performed for surveillance (p = 0.21). However, after left-sided colectomy, both types of lesions were more commonly detected in those who received ≥ 3 colonoscopies than in those with one or two colonoscopies (p = 0.04).

CONCLUSION

A remaining right colon after left-sided colectomy was associated with a higher risk of developing AA and MC. Physicians should consider performing surveillance colonoscopy more frequently if the right colon remains after surgery.

Risk Stratification Based on Synchronous Neoplasia and Clinical Physicochemical Characteristics Predicts a Higher Incidence of Metachronous Advanced Neoplasia in Patients Undergoing Colorectal Resection for Colorectal Cancer

Purpose

Patients who undergo primary colorectal cancer (CRC) resection remain at increased risk for metachronous advanced neoplasia (MAN) in the remnant colorectum. This study aimed to investigate the incidence and clinicopathological characteristics predictive of MAN development in the residual colon after surgery.

Patients and Methods

We retrospectively reviewed 450 primary CRC cases referred to our hospital during a 4-year period. Univariate and multivariate analyses were performed to identify risk factors for MAN. The cumulative incidence of MAN was evaluated by the Cox proportional hazards model.

Results

MAN development was confirmed in 78 of the 450 patients (17.3%). Overall 1-, 2-, 3-, and 5-year cumulative probabilities were 0.9%, 4.8%, 9.8%, and 16.1%, respectively, for MAN. Among the clinical and colonoscopic factors at baseline, the independent factors that were significantly associated with MAN were synchronous neoplasia, carcinoembryonic antigen (CEA) level ≥10.0 ng/mL, and index cancer size ≥50 mm. The cumulative probability of MAN was significantly higher for patients with synchronous advanced neoplasia (SAN) than for those without synchronous neoplasia (P = 0.000). A subgroup analysis of patients based on the CEA level and index cancer size indicated that CEA ≥10 ng/mL and index cancer ≥50 mm resulted in a significantly higher cumulative probability of MAN (P = 0.039).

Conclusion

Patients with SAN or high preoperative serum CEA levels and large index cancer are at increased risk for early-onset MAN. More intensive surveillance strategies may be appropriate for these groups. Risk stratification based on synchronous neoplasia and clinical physicochemical characteristics requires further investigations involving modified appropriate postoperative colonoscopic surveillance schedules.

Yield of Surveillance Colonoscopies 1 Year After Curative Surgical Colorectal Cancer Resections

BACKGROUND & AIMS

Endoscopic surveillance after curative colorectal cancer (CRC) resection is routine. However, there is controversy whether the 1-year interval between preoperative and postoperative colonoscopy is justified owing to improved colonoscopy standards. We aimed to assess the yield of surveillance colonoscopies 1 year after CRC surgery.

METHODS

We performed a retrospective cohort study of 572 patients (54.9% male; mean age, 66.2 ± 9.9 y), who underwent curative surgical resection of a first CRC from June 2013 through April 2016 in the Northwest region of The Netherlands. Patients were included if a complete clearing colonoscopy was performed before surgery and the interval between the preoperative and postoperative colonoscopy was 12 months (range, 6-20 mo), conforming to Dutch guidelines. The primary outcome of the study was the yield of CRC at the surveillance colonoscopy performed 1 year after curative resection. A secondary outcome was the yield of advanced neoplasia.

RESULTS

After a mean surveillance interval of 13.7 months (±2.8 mo), 10 of 572 patients (1.7%; 95% CI, 0.7%-2.8%) received a diagnosis of CRC. Of these, 5 CRCs were apparently metachronous cancers (3 were stage III or IV) and 5 were recurrences at the anastomosis (1 was stage IV). In 11.4% of patients (95% CI, 8.9%-13.8%), advanced neoplasia was detected at the 1-year follow-up colonoscopy. Synchronous advanced neoplasia at baseline colonoscopy was a risk factor for detection of advanced neoplasia at the follow-up colonoscopy (odds ratio, 2.2; 95% CI, 1.3-3.8; P ≤ .01).

CONCLUSIONS

Despite high colonoscopy quality, the yield of CRC at surveillance colonoscopy 1 year after CRC resection was 1.7%. These were metachronous CRCs and recurrences, often of advanced stage. The high yield justifies the recommendation of a 1-year surveillance interval after surgical CRC resection.

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.

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.

Risk factors for metachronous colorectal cancer or polyp: A systematic review and meta-analysis

BACKGROUND AND AIM

We conducted a systematic review and meta-analysis to identify personal, lifestyle, and tumor-related risk factors for metachronous colorectal cancer (CRC) and polyp.

METHODS

Relevant studies were identified by searching MEDLINE, Web of Science and Cochrane Central Register through 15 May 2016. Estimates for associations were summarized using random effects models.

RESULTS

Fifty-five studies were included in the review. For individuals who had a CRC resection, having a synchronous polyp was a risk factor for metachronous CRC or polyp (relative risk [RR], 2.04; 95% confidence interval [CI], 1.48-2.82) and having a synchronous CRC (RR, 1.90; 95% CI, 1.25-2.91) and proximally located CRC (RR, 2.12; 95% CI, 1.24-3.64) were risk factors for metachronous CRC. For individuals who had a polypectomy, larger size (RR, 4.26; 95% CI, 2.11-8.57) or severe dysplasia of the initial polyp (RR, 5.15; 95% CI, 2.02-13.14), and having a synchronous polyp (RR, 2.52; 95% CI, 1.35-4.73) were risk factors for metachronous CRC; and a family history of CRC (RR, 1.90; 95% CI, 1.26-2.87), having a synchronous polyp (RR, 2.47; 95% CI, 1.74-3.50) and a larger size (RR, 1.49; 95% CI, 1.03-2.15) and proximal location of the initial polyp (RR, 1.20; 95% CI, 1.02-1.40) were risk factors for metachronous polyp. Meta-regression showed duration of follow-up was not a source of heterogeneity for most associations. There was no evidence that lifestyle factors were associated with metachronous CRC or polyp risk.

CONCLUSION

A comprehensive list of risk factors identified for metachronous CRC or polyp may have important clinical implications.

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.

Tumor size is an independent risk predictor for metachronous colorectal cancer

Non-hereditary colorectal cancer (CRC) patients are at higher risk of developing independent metachronous CRC than cancer-naïve individuals, but the reason is unknown. We studied metachronous CRC risk factors among one thousand five Japanese CRC patients who underwent surgery for CRC. Relative hazard risk of clinical and pathological features was assessed by univariate and multivariate Cox's proportional hazard regression analysis. Observed metachronous CRC incidence was also compared with the expected cancer incidence of the general population in Japan. Twenty-seven metachronous CRCs developed in 24 patients (2.4%) during a follow-up period of 3,676 person-years. Multivariate analysis revealed two factors associated with a high metachronous CRC risk: synchronous CRC (HR = 6.13; p = 1.3x10(-4)) and tumor size ≥ 6.5 cm (HR = 4.34; p = 1x10(-3)). Patients with either synchronous or large solitary tumors exhibited a higher risk for metachronous CRC than patients with solitary small tumors (HR = 7.3; p = 4.3x10(-6)) and that the general Japanese population (SIR = 7.01; p = 3.5x10(-9)), while patients with solitary small tumors did not (SIR = 1.07; p = 0.8). If patients younger than 60 years were excluded, the observations remained unchanged, with tumor size becoming stronger predictor (HR = 5.67; p = 1.7x10(-4)) than the presence of synchronous CRC (HR = 5.34; p = 9.6x10(-4)). Our novel finding that primary tumor size is a strong independent risk factor for metachronous CRC increases the sensitivity of prediction more than twice the presence of synchronous CRC. Our data provides new insights to assess the risk for metachronous lesions that should improve the surveillance regimen for CRC.

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.

Colorectal cancer screening and surveillance in the elderly: updates and controversies

Colorectal cancer is common worldwide, and the elderly are disproportionately affected. Increasing age is a risk factor for the development of precancerous adenomas and colorectal cancer, thus raising the issue of screening and surveillance in older patients. Elderly patients are a diverse and heterogeneous group, and special considerations such as comorbid medical conditions, functional status and cognitive ability play a role in deciding on the utility of screening and surveillance. Colorectal cancer screening can be beneficial to patients, but at certain ages and under some circumstances the harm of screening outweighs the benefits. Increasing adverse events, poorer bowel preparation and more incomplete examinations are observed in older patients undergoing colonoscopy for diagnostic, screening and surveillance purposes. Decisions regarding screening, surveillance and treatment for colorectal cancer require a multidisciplinary approach that accounts not only for the patient’s age but also for their overall health, preferences and functional status. This review provides an update and examines the challenges surrounding colorectal cancer diagnosis, screening, and treatment in the elderly.

Colonoscopic surveillance after colorectal cancer resection: who needs more intensive follow-up?

BACKGROUND/AIMS

Although there are guidelines for colonoscopic surveillance after colorectal cancer (CRC) surgery, the data evaluating the effectiveness of these guidelines are limited. We determined the risk factors for metachronous neoplasia (MN) by performing annual colonoscopy examinations after curative resection.

METHODS

We performed annual colonoscopic surveillance on stage I-III CRC patients after curative resection. We stratified the patients based on the advanced neoplasia risk during the surveillance.

RESULTS

Advanced MN detected was in 59 (13.1%) of 451 patients. Overall, the cumulative incidence of advanced MN was 17.3% at 5 years. By the multivariate analysis, the risk factors for advanced MN were male gender, age >65, left-sided index cancer and being in the high-risk group. The cumulative incidence of advanced MN was 38.9% at 5 years in the high-risk group. Among the patients who had advanced MN, secondary advanced MN was detected in 13 patients (22.0%) with a subsequent colonoscopy. The 2-year cumulative incidence of secondary advanced MN was 16.9%. Four (0.88%) patients had metachronous CRC during the surveillance and the interval from the index CRC was a median of 58.5 months.

CONCLUSIONS

Although the current follow-up guidelines for colonoscopic surveillance after CRC are well established, the high-risk group calls for more meticulous follow-up, which should be continued for a sufficient time.

Colorectal cancer of the elderly

OPINION STATEMENT

Colorectal cancer (CRC) disproportionately affects the elderly. Older age is a strong risk factor for both the development of precancerous adenomas and CRC, thus raising the issue of screening and surveillance in older patients. However, screening and surveillance decisions in the elderly can be complex and challenging. Elderly patients are a diverse and heterogeneous group and special considerations such as co-morbid medical conditions, functional status, and cognitive ability play a role in one's decisions regarding the utility of screening and surveillance. Such considerations also play a role in factors related to screening modalities, such as colonoscopy, as well as CRC treatment options and regimens. This review addresses many of the unique factors associated with CRC of the elderly and critically examines many of the controversies and challenges surrounding CRC in older patients.

Incidence and risk factors of metachronous colorectal neoplasm after curative resection of colorectal cancer in Korean patients

OBJECTIVE

Early detection and endoscopic removal of metachronous neoplasms are important preventive strategies for patients with colorectal cancer (CRC) after curative tumor resection. We aimed to determine the incidence of and the risk factors for metachronous colorectal neoplasms after curative resection for CRC.

METHODS

We retrospectively reviewed clinical data of patients who underwent curative resection for CRC at the National Cancer Center, Korea, from July 2004 to July 2007 and were followed up for a mean duration of 40.7 months. The incidence of and the risk factors for developing metachronous neoplasms were analyzed.

RESULTS

A total of 1049 patients were included in this study. A follow-up colonoscopy showed that 454 (43.3%) patients developed metachronous neoplasms, including 46 (4.4%) with advanced adenoma or cancer. Univariate analyses revealed that age ≥ 60 years, male gender, diabetes mellitus, hypertension, synchronous adenoma, synchronous multiple adenoma and synchronous advanced adenoma were associated with the development of metachronous neoplasms. Baseline risk factors associated with metachronous advanced neoplasm were age ≥ 60 years, synchronous multiple adenoma and synchronous advanced adenoma. Multivariate analysis showed that age ≥ 60 years, synchronous adenoma and diabetes mellitus were risk factors for the development of metachronous neoplasms. The cumulative incidence of metachronous neoplasms was higher in patients with these risk factors than in those without.

CONCLUSIONS

Elder age, synchronous adenoma and diabetes mellitus are risk factors for developing metachronous neoplasia. Therefore, careful surveillance colonoscopy are necessary for these patients.

How often should we perform surveillance colonoscopy after surgery for colorectal cancer?

PURPOSE

Surveillance colonoscopy is undertaken after resection of colorectal cancer to detect and treat local recurrence and metachronous lesions, with the aim of improving survival. This study aimed to clarify the current timing of surveillance colonoscopies and evaluate the rates of local recurrence and metachronous tumors.

METHODS

We retrospectively analyzed data from 459 patients who underwent surveillance colonoscopy at our institution after curative resection of colorectal cancer. The number and timing of surveillance colonoscopies, incidence of local recurrence and metachronous lesions, pathological findings of lesions, treatment of lesions, and outcomes were recorded.

RESULTS

The first surveillance colonoscopy was undertaken at 6-18 months after surgery in 73 % of patients. Local recurrence was detected in three cases (0.7 %), all during the first surveillance colonoscopy, which was performed >1 year after surgery. These three patients all underwent additional surgery and were alive 5 years later. Invasive metachronous cancers were detected in six patients (1.3 %) at 18-57 months after surgery, and advanced adenomas were detected in 30 patients.

CONCLUSION

Considering the low incidence of postoperative lesions and the timing of lesion detection, reducing the number of surveillance colonoscopies after surgery for colorectal cancer may be appropriate.

Polyp surveillance after surgery for colorectal cancer

PURPOSE

Although it is known that those patients who have developed colorectal cancer (CRC) are at a higher risk to develop metachronous adenoma or CRC, no study has been performed to analyze the relationship between the risk factors and the time course for the formation of postoperative adenoma using survival analysis.

METHODS

One hundred seventy-six patients with CRC,who had received surgical resection, were endoscopically followed-up to detect the development of metachronous adenoma or adenocarcinoama. The association between the risk factors such as age, synchronous adenomas with index CRC or other clinicopathological variables and the formation of postoperative adenoma was assessed using the logrank test and the Cox proportional hazard model.

RESULTS

Age over 60, synchronous lesions at the time of surgery for primary CRCs and presence of diabetes mellitus(DM) as the associated disease were positively related to the formation of postoperative adenoma. Among those patients with the three risk factors, only 27.8% remained adenoma-free during 5 years after operation, whereas in the group without any risk factor, it was 90.4%.

CONCLUSIONS

From our data, age over 60, synchronous adenomas or CRCs and DM were the potential risk factors for the postoperative formation of adenoma or CRC, and they should be taken into consideration when defining the appropriate interval of postoperative colonoscopy.

Advanced synchronous adenoma but not simple adenoma predicts the future development of metachronous neoplasia in patients with resected colorectal cancer

BACKGROUND

Patients with resected colorectal cancer remain at a high risk for developing metachronous neoplasia in the remnant colorectum. The aim of this study was to identify baseline clinical and colonoscopic features predictive of metachronous neoplasia after curative resection of colorectal cancer.

METHODS

The baseline clinical and colonoscopic data and follow-up details of 503 patients who had colonoscopic surveillance after curative colorectal resection between January 2000 and October 2005 in a single tertiary institution were analyzed. Univariate and multivariate analyses were done to identify risk factors for metachronous adenoma.

RESULTS

Metachronous adenomas were diagnosed in 176 patients (35.0%) and advanced adenomas in 39 (7.8%) during the follow-up period (35.7+/-20.9 mo). Among the clinical and colonoscopic factors at baseline, advanced age (> or = 60 y) (odds ratio (OR)=3.64; 95% confidence intervals (CI), 1.55-8.52), the presence of advanced synchronous adenoma (OR=4.38; 95% CI, 1.77-10.85), and longer total follow-up period (OR=1.03; 95% CI, 1.01-1.04) were independently correlated with developing advanced metachronous adenoma. Patients who had synchronous tubular adenoma without advanced features at baseline were not found to have an increased risk for future development of advanced metachronous adenoma compared with those in the synchronous adenoma-free group (OR=1.75; 95% CI, 0.69-4.43, P=0.650).

CONCLUSIONS

Our data showed that patients with advanced synchronous adenoma at baseline were identified to have an increased risk of advanced metachronous neoplasia during a longer follow-up period but those with tubular adenoma without advanced features at baseline were not.

The high yield of 1-year colonoscopy after resection: is it the handoff?

BACKGROUND

This study aimed to determine the diagnostic yield of colonoscopy 1 year after colorectal cancer (CRC) resection based on whether the index colonoscopy was performed by the operating surgeon.

METHODS

All patients undergoing surgery for colorectal cancer by two colon and rectal surgeons at a university hospital from 1991 to 2005 were identified from the tumor registry. Those patients with a complete preoperative colonoscopy by any physician and a 1-year follow-up examination by the operating surgeon were selected for the study population. Family history of colorectal cancer, tumor location, endoscopist, presence of synchronous neoplasms, and findings of 1-year colonoscopy were recorded. Fisher's exact test was used to compare the probability of finding any adenoma, advanced adenoma, or invasive cancer based on the index endoscopist.

RESULTS

Of the 719 patients who underwent resection during the study period, 432 met the inclusion criteria. The index colonoscopy for 117 of these patients (27.1%) was performed by one of the two surgeons. Overall, 10 patients (2.3%) had a "new" cancer diagnosed at 1 year, and 1 patient (0.2%) had a local recurrence. Patients whose index colonoscopy was performed by their operating surgeon appeared less likely to have an advanced lesion found at 1 year (5.1% vs 11.4%; p = 0.06). The index colonoscopy for 9 of the 10 of cancers found at 1 year was not performed by the operating surgeon.

CONCLUSIONS

Colonoscopy 1 year after CRC resection is clearly justified. An index colonoscopy by the operating surgeon eliminates a "handoff" and may diminish the incidence of high-risk lesions at 1 year.

Q&A on diagnosis, screening and follow-up of colorectal neoplasia

The impressive and brisk evolution of medical science prevents many physicians from a thorough update on all the research fields. Colorectal cancer diagnosis, screening and follow-up is well known to require a multi-disciplinary approach, as it is faced by several specialties such as primary care physicians, gastroenterologists, non-gastroenterologist internists, radiologists and surgeons. To address this issue in a mutual perspective, we focused on the main points of the epidemiology, diagnosis, screening and follow-up of colorectal neoplasia by using a simple "Question & Answers" structure.

Prospective observation of small adenomas in patients after colorectal cancer surgery through magnification chromocolonoscopy

PURPOSE

This study was designed to confirm the safety of not removing small adenoma in patients who undergo colorectal cancer surgery.

METHODS

Patients who underwent surveillance colonoscopy after surgery were enrolled. The study was approved by our institutional review board. Colonoscopy was performed with magnification chromocolonoscopy. Benign adenomas of 6 mm or less in size, diagnosed based on both nonmagnified and magnified observation, were left unresected with a maximum of three polyps per patient. The sites of the polyps were marked by tattooing. Interval colonoscopy was performed predominantly yearly or biennially. Increase in size by 2 mm or larger was defined as significant. In follow-up, polyps were removed if they grew larger than 6 mm, were suspicious for high-grade dysplasia, or the patients requested to have polyps removal.

RESULTS

Five hundred polyps in 284 patients met the above criteria and were not resected, and 412 polyps were followed by repeat colonoscopy. The mean observation period was 3.6+/-2.2 years and the mean number of repeat colonoscopy was 3.6+/-1.6. At the final colonoscopy, 71 percent of 412 polyps showed no change in size, 15 percent increased, 3 percent decreased, and 11 percent could not be identified. Eighty-eight polyps were resected endoscopically, and histology showed neither cancer nor adenomas with high-grade dysplasia. Two hundred fifty-five polyps detected in the same patient cohort during index/repeat colonoscopy were removed, including four adenomas with high-grade dysplasia and two T1 cancers.

CONCLUSIONS

Leaving small polyps is safe even in patients who have undergone colorectal cancer surgery, provided that careful observation is guaranteed.

Detection of metachronous neoplasms in colorectal cancer patients: identification of risk factors

PURPOSE

Patients with colorectal cancer have a high risk of developing metachronous neoplasms. Identification of predictive factors associated with such conditions would allow individualized follow-up strategies in these patients. This study was designed to identify individual and familial factors associated with the development of metachronous colorectal neoplasms in patients with colorectal cancer.

METHODS

In the context of a prospective, multicenter, general population-based study-the EPICOLON project-all patients with colorectal cancer attended in ten Spanish hospitals during a one-year period were included. Patients with familial adenomatous polyposis or inflammatory bowel disease were excluded. All patients were monitored by colonoscopy within two years of the diagnoses. Demographic, clinical, pathologic, molecular (microsatellite instability status and immunohistochemistry for MSH2 and MLH1), and familial characteristics (fulfillment of Amsterdam I or II criteria, and revised Bethesda guidelines) were analyzed.

RESULTS

A total of 353 patients were included in the study. At two years of follow-up, colonoscopy revealed the presence of adenomas in 89 (25 percent) patients and colorectal cancer in 14 (3.9 percent) patients, in 7 cases restricted to anastomosis. Univariate analysis demonstrated that development of metachronous neoplasm (adenoma or colorectal cancer) was associated with personal history of previous colorectal cancer (odds ratio, 5.58; 95 percent confidence interval, 1.01-31.01), and presence of previous or synchronous adenomas (odds ratio, 1.77; 95 percent confidence interval, 1.21-3.17). Although nonstatistical significance was achieved, metachronisms were associated with gender (P<0.09) and differentiation degree (P<0.08). Multivariate analysis identified previous or synchronous adenomas (odds ratio, 1.98; 95 percent confidence interval, 1.16-3.38) as independent predictive factor. Neither presence of tumor DNA microsatellite instability nor family history correlated with the presence of metachronous neoplasms.

CONCLUSIONS

Patients with previous or synchronous colorectal adenoma have an increased risk of developing metachronous colorectal neoplasms. Accordingly, this subgroup of patients may benefit from specific surveillance strategies.

Outcome of follow-up colon examination among a population-based cohort of colorectal cancer patients

BACKGROUND & AIMS

The benefit of colonoscopy in the follow-up of colorectal cancer survivors is uncertain, and findings of surveillance colonoscopy are not well-characterized. We sought to estimate survival among colorectal cancer patients according to receipt of a follow-up colon examination and to describe the findings of such exams.

METHODS

We studied health maintenance organization enrollees with colorectal cancer who underwent surgical resection. Mortality was estimated by using survival analysis, and findings of colon examinations were determined by review of pathology reports.

RESULTS

One thousand two patients were eligible for study; 5-year survival was higher (76.8%) for patients who had at least one follow-up exam than for patients who did not undergo follow-up (52.2%, P < .0001). In multivariate analysis, colon examination remained independently associated with improved survival (hazard ratio, 0.58; 95% confidence interval, 0.44-0.75). Twenty patients (3.1%) were diagnosed with a second colorectal cancer, including 9 cancers detected within 18 months of initial cancer diagnosis. Advanced neoplasia was more common (15.5%) among patients followed up between 36-60 months after diagnosis compared with patients followed up within 18 months (6.9%, P = .02). History of adenomas was associated with advanced neoplasia on follow-up (P = .002). Patients with advanced neoplasia on initial follow-up were at high risk for advanced neoplasia on subsequent examinations (13/16, 81%).

CONCLUSIONS

After colorectal cancer resection, patients have a high risk of interval cancers, some of which represent missed lesions at initial diagnosis. Therefore, surveillance colonoscopy within 1 year of initial diagnosis is warranted. After adjusting for key variables, endoscopic surveillance is associated with improved survival.

Resection of asynchronous quadruple advanced colonic carcinomas followed by reconstruction with ileal interposition between the transverse colon and rectum

We report an extremely rare case of resectable asynchronous quadruple advanced colonic carcinomas. Successful reconstruction was performed after resection with an ileal interposition between the remaining colon and rectum, and the patient recovered bowel function. Resections of the four colonic lesions in three operations allowed us to leave a portion of the large bowel and to thereby preserve the rectum and a portion of the transverse colon. After resection of the third and fourth cancer lesions, we reconstructed the large bowel with ileal segment interposition between the residual transverse colon and rectum, leaving a 15-cm-long segment portion of the transverse colon. This surgical procedure is an option for reconstruction after left-sided colectomy.

Guidelines for colonoscopy surveillance after cancer resection: a consensus update by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer

Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stages II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double-contrast barium enema or computed tomography colonography should be performed preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that examination is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see "Guidelines for Colonoscopy Surveillance After Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society"). Shorter intervals also are indicated if the patient's age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence compared with those with colon cancer. Although effectiveness is not proven, performance of endoscopic ultrasound or flexible sigmoidoscopy at 3- to 6-month intervals for the first 2 years after resection can be considered for the purpose of detecting a surgically curable recurrence of the original rectal cancer.

Colorectal cancer screening: today and tomorrow

Colorectal cancer remains a disease with significant morbidity and mortality. However, the prognosis can be greatly improved with early detection. Here, we review the current screening modalities and guidelines for patients at average, moderate, and high risk for colorectal cancer. New experimental modalities are also introduced.

Clinical features, diagnosis, treatment and prognosis of multiple primary colorectal carcinoma

AIM: To investigate the clinical features, diagnosis, treatment and prognosis of multiple primary colorectal carcinomas (MPCC).

METHODS: A retrospective analysis of 37 patients with MPCC from 1974 to 1998 was carried out.

RESULTS: The incidence of MPCC was 2.74% (37/1348) in patients with primary colorectal carcinomas, 15 cases of them were patients with synchronous carcinomas (SC) and 22 cases were diagnosed as metachronous carcinomas (MC). Most tumors were located in the right colon and rectum. Fifty-five percent (12/22) of MC were diagnosed within 3 years after tumor resection and 41% (9/22) of MC occurred after 8 years. Radical resections were performed in all patients except for 1 case. The 5-year survival rate of SC was 72.7% (8/11) and that of MC after the first cancer and second cancer was 71.4% (15/21) and 38.9% (7/18), respectively.

CONCLUSION: The results indicate the importance of complete preoperative examination, careful intraoperative exploration and periodic postoperative surveillance. Early diagnosis and radical resection can increase survival rate of MPCC.

Adenoma recurrences after resection of colorectal carcinoma: results from the Southwest Oncology Group 9041 calcium chemoprevention pilot study

BACKGROUND

Colorectal adenomas are the usual precursors to carcinoma in sporadic and hereditary colorectal cancers (CRC).

METHODS

A total of 220 CRC patients (stages 0, I, and II) were randomized prospectively in a double-blind pilot study of calcium chemoprevention by using recurrent colorectal adenomas as a surrogate end point. This trial is still in progress, and we report the preliminary findings on adenoma recurrence rates.

RESULTS

Synchronous adenomas were present in 60% of patients, and cancer confined in a polyp was present in 23% of patients. The overall cumulative adenoma recurrence rate was 31% (19% in the first year, 29% for 2 years, and 35% for 3 years). The recurrence rates were greater for patients with synchronous adenomas: 38% at 3 years (P =.01). Lower stage was associated with higher adenoma recurrence rates (P =.04). Factors including age, sex, site of primary cancer, and whether the cancer was confined to a polyp were not significantly associated with differences in adenoma recurrence rates.

CONCLUSIONS

The substantial adenoma recurrence rate in patients resected of CRC justifies colonoscopic surveillance on a periodic basis. Patients with higher rates of adenoma recurrences, such as CRC with synchronous adenomas, are ideal subjects for chemoprevention trials.

Clinical and sociodemographic factors associated with colon surveillance among patients with a history of colorectal cancer

BACKGROUND

Substantial variability in the use of colon surveillance among colorectal cancer survivors has been reported. This study sought to examine trends in the use of colon surveillance among patients who have had colorectal cancer and to investigate factors associated with utilization.

METHODS

Health maintenance organization enrollees with a diagnosis of local or regional colon or rectal cancer between January 1993 and December 1999 were studied. Receipt of a colon examination by colonoscopy or by flexible sigmoidoscopy, together with barium contrast radiography of the colon was determined from automated clinical records, and rates of colon surveillance were estimated by using survival analysis.

RESULTS

A total of 1002 patients with a diagnosis of colorectal cancer met inclusion criteria for the study. Colon examinations were performed in 61% of patients within 18 months of diagnosis and in 80% of patients within 5 years of diagnosis. The median time from diagnosis to first colon surveillance examination (14 months) was unchanged over the study period, but the interval between first and second surveillance examinations increased by 17 months (p<0.001). Patients over 80 years of age (relative risk=0.32; 95% CI[0.22, 0.45]) and those with rectal cancer (relative risk=0.80; 95% CI[0.66, 0.97]) were less likely to undergo surveillance. Higher socioeconomic status (relative risk=1.29; 95% CI[1.03, 1.61]) and being married (relative risk=1.27; 95% CI[1.05, 1.53]) were associated with greater utilization. There was lower utilization among African American patients (relative risk=0.70; p=0.14) and increased utilization among other minorities (relative risk=1.47; p=0.06).

CONCLUSIONS

There is substantial variability in the use of colon examination for surveillance in patients with a history of colorectal cancer, and clinical and sociodemographic factors appear to influence the likelihood of surveillance.