Metachronous colorectal carcinoma

Joint effect of RRP9 and DDX21 on development of colorectal cancer and keloid

BACKGROUND

Colorectal cancer (CRC) is a common malignancy in the gastrointestinal tract. Keloid refers to abnormal scar tissue that forms on the skin or mucous membrane. The relationship between RRP9 and DDX21 and the two diseases is unclear.

METHODS

Download the colorectal cancer dataset GSE134834, GSE206800, GSE209892 and keloid dataset GSE44270 from the GEO database. Differentially expressed genes (DEGs) were screened and weighted gene co-expression network analysis (WGCNA) was performed. The construction and analysis of protein-protein interaction (PPI) network, functional enrichment analysis, gene set enrichment analysis (GSEA). Gene expression heat map was drawn. The comparative toxicogenomics database (CTD) analysis was performed to find diseases most related to core genes. TargetScan screened miRNAs that regulated central DEGs. We conducted experimental validation using Western blotting and Polymerase Chain Reaction (PCR).

RESULTS

In the colorectal cancer dataset and the scar tissue dataset, we identified 1380 DEGs and 1000 DEGs, respectively. The enrichment pattern for scar tissue was similar to that of colorectal cancer. We identified two core genes, RRP9 and DDX21. CTD analysis indicated that RRP9 and DDX21 are associated with proliferation, scar tissue, colorectal tumors, scleroderma, and inflammation. We found that the core genes (RRP9 and DDX21) were highly expressed in colorectal cancer and scar tissue samples, while their expression was lower in normal samples. This was further validated through Western blotting (WB) and Polymerase Chain Reaction (PCR).

CONCLUSIONS

The higher the expression of RRP9 and DDX21 in colorectal cancer and keloid, the worse the prognosis.

Metachronous colorectal cancer have a similar microsatellite instability frequency but a lower infiltration of lymphomononuclear cells than primary lesions

BACKGROUND

An increased risk of metachronous colorectal cancer is usually associated with microsatellite instability occurring in Lynch syndrome. However, not all patients with metachronous colorectal cancer have microsatellite instability. The density of tumor-infiltrating lymphocytes is an independent predictor of outcome in patients with colorectal cancer, and a fascinating hypothesis is that they can be involved in the onset of metachronous colorectal cancer. The aim of this study was to analyze the tumor microenvironment and tumor mutation frequency in sporadic and metachronous colorectal cancer.

METHODS

The clinical and pathological records of a series of consecutive colorectal cancer patients who were operated on from 2015 to 2019 were retrieved for this retrospective study. We defined metachronous colorectal cancer as a second colorectal cancer that appeared at least 1 year after the primary one, and sporadic colorectal cancer as those that did not have a metachronous colorectal cancer. Histology for the infiltration of intratumoral lymphomononuclear cells, immunohistochemistry for MLH1, PMS2, MSH2, and MSH6, and mutational analysis of BRAF, KRAS, and NRAS were all performed. Sporadic colorectal cancer and metachronous colorectal cancer were compared. Nonparametric tests were used for small sample size comparison.

RESULTS

In the study, 238 patients were operated on for colorectal cancer at the General Surgery Unit of the Azienda Ospedaliera di Padova from 2015 to 2019. We identified 26 patients with metachronous colorectal cancer, and only 3 of them had had adjuvant therapy after the primary colorectal cancer. No difference was observed in terms of cancer stage between metachronous and sporadic colorectal cancer. Mismatch repair gene deficiencies and microsatellite instability frequency was similar in metachronous colorectal cancer and in sporadic colorectal cancer (P = .77). Likewise, the mutation frequency of BRAF and KRAs was similar in the 2 groups (P = .75 and P = .21, respectively). To the contrary, the absence of infiltration of lymphomononuclear cells within the tumor (P = .004) in patients with metachronous colorectal cancer was more frequent and they tended to have a higher frequency of NRAS mutation (P = .06).

CONCLUSION

Our study showed that, rather unexpectedly, microsatellite instability frequency was similar in metachronous and sporadic colorectal cancer. Moreover, our data suggest that an altered immune microenvironment may be a crucial factor, permitting the occurrence of metachronous colorectal cancer. In fact, the absence of lymphomononuclear cells can be the substrate for a weak immune response to cancer neoantigens, opening the way to a second primary colorectal cancer.

Appendiceal tumors and pseudomyxoma peritonei: French Intergroup Clinical Practice Guidelines for diagnosis, treatments and follow-up (RENAPE, RENAPATH, SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, ACHBT, SFR)

INTRODUCTION

This document is a summary of the French Intergroup guidelines regarding the management of appendicular epithelial tumors (AT) and pseudomyxoma peritonei (PMP) published in March 2020, available on the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org).

METHODS

All French medical societies specialized in the management of AT and PMP collaboratively established these recommendations based on literature until December 2019 and the results of a Delphi vote carried out by the Peritoneal Surface Oncology Group International experts, and graded into 4 categories (A, B, C, Expert Agreement) according to their level of evidence.

RESULTS

AT and PMP are rare but represent a wide range of clinico-pathological entities with several pathological classification systems and different biological behaviors. Their treatment modalities may vary accordingly and range from simple surveillance or laparoscopic appendectomy to complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) and / or systemic chemotherapy. The prognosis of these neoplasms may also largely vary according to their pathological grade and spreading at diagnosis or during the follow-up. Given the rarity of certain situations, the therapeutic strategy adapted to each patient, must be discussed in a specialized multidisciplinary meeting after a specialized pathological and radiological pre-therapeutic assessment and a clinical examination by a surgeon specializing in the management of rare peritoneal malignancies.

CONCLUSION

These recommendations are proposed to achieve the most beneficial strategy in a daily practice as the wide range and the rareness of these entities renders their management challenging. These guidelines are permanently being reviewed.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

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.

Colonoscopy Surveillance After Colorectal Cancer: the Optimal Interval for Follow-Up

PURPOSE

Patients who have undergone curative surgery for colorectal cancer are at risk of developing a metachronous colorectal tumour or anastomotic recurrence. The aim of this study was to determine the incidence of recurrent colorectal cancer in a cohort of patients who participated in a colonoscopy surveillance programme.

METHODS

This single-centre retrospective observational cohort study included patients who underwent curative surgery for colorectal cancer between 2005 and 2015. All reports of postoperative colonoscopies were retrieved to calculate the incidence rates of recurrence and metachronous colorectal cancer.

RESULTS

Of 2420 patients, 1644 (67.9%) underwent at least one postoperative colonoscopy and 776 (32.1%) did not. In 1087 patients, colonoscopy was performed in the first 18 months after surgery, which detected 34 (3.1%) instances of metachronous colorectal tumours or anastomotic recurrence. Thirty-three additional patients were also diagnosed with recurrent colorectal cancer, but the tumours were detected by other diagnostic modalities or detected perioperatively, rather than by colonoscopy.

CONCLUSIONS

Patients with a history of colorectal cancer have an increased risk for a second colorectal tumour. Therefore, we recommend a colonoscopic surveillance programme with the first colonoscopy performed 1 year after curative surgery, which is in accordance with national guidelines.

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.

Surgical treatment of multiple sporadic colorectal carcinoma

Aim: Many aspects of the surgical management of multiple sporadic colorectal cancer syndrome, either synchronous and metachronous, remain to be cleared, in particular the prognostic influence of the extent of surgical resection. Method: A retrospective review was performed of patients diagnosed with multiple colorectal cancer from 1982 to May 2010. Clinical and pathologic data were collected and reviewed. Survival analysis was performed. Results: We identified 23 patients with multiple sporadic colorectal cancers, of which 8 had synchronous (SC) and 15 metachronous cancers (MC). Of the MC patients, 2 (13%) had the second cancer within 2 years, 4 (27%) in the time period of 2-5 years and 9 (60%) after 5 years. Twenty-one patients underwent multiple segmental resections; 2 patients underwent subtotal colectomy. The 5-year overall survival rate of SC and MC patients was 100% and 87% (p<0.001) respectively. The 5-year overall survival rate of multiple segmental resection patients and subtotal colectomy was 94% and 75% (p=0.655) respectively. Conclusion: Either synchronous and metachronous MSCRC patients showed good prognosis independently from to the extent of resection. Our results support a less aggressive biological behaviour allowing a more conservative management. Multiple segmental colorectal resections seem appropriate from an oncologic point of view in MSCRC patients. (www.actabiomedica.it)

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.

Risk factors for metachronous colorectal cancer following a primary colorectal cancer: A prospective cohort study

Individuals diagnosed with colorectal cancer (CRC) are at risk of developing a metachronous CRC. We examined the associations between personal, tumour-related and lifestyle risk factors, and risk of metachronous CRC. A total of 7,863 participants with incident colon or rectal cancer who were recruited in the USA, Canada and Australia to the Colon Cancer Family Registry during 1997-2012, except those identified as high-risk, for example, Lynch syndrome, were followed up approximately every 5 years. We estimated the risk of metachronous CRC, defined as the first new primary CRC following an interval of at least one year after the initial CRC diagnosis. Observation time started at the age at diagnosis of the initial CRC and ended at the age at diagnosis of the metachronous CRC, last contact or death whichever occurred earliest, or were censored at the age at diagnosis of any metachronous colorectal adenoma. Cox regression was used to derive hazard ratios (HRs) and 95% confidence intervals (CIs). During a mean follow-up of 6.6 years, 142 (1.81%) metachronous CRCs were diagnosed (mean age at diagnosis 59.8; incidence 2.7/1,000 person-years). An increased risk of metachronous CRC was associated with the presence of a synchronous CRC (HR = 2.73; 95% CI: 1.30-5.72) and the location of cancer in the proximal colon at initial diagnosis (compared with distal colon or rectum, HR = 4.16; 95% CI: 2.80-6.18). The presence of a synchronous CRC and the location of the initial CRC might be useful for deciding the intensity of surveillance colonoscopy for individuals diagnosed with CRC.

Nomogram prediction of metachronous colorectal neoplasms in patients with colorectal cancer

OBJECTIVE

To construct a predictive model of postoperative colorectal neoplasm development using a nomogram.

BACKGROUND

Although patients with colorectal cancer (CRC) are known to be at high risk of developing metachronous adenoma or CRC, no statistical model for predicting the incidence of postoperative colorectal lesions has been reported.

METHODS

A total of 309 CRC patients who underwent surgical resection received regular endoscopic follow-up to detect the development of metachronous adenoma or adenocarcinoma. The patients were divided into the derivation set (n = 209) and the validation set (n = 100). The nomogram to predict the 3- and 5-year adenoma-free survival rates was constructed using the derivation set, and a calibration plot and concordance index (c-index) were calculated. The predictive utility of the nomogram was validated in the validation set.

RESULTS

Sex, age, and number of synchronous lesions at the time of surgery for primary CRC were adopted as variables for the nomogram. The nomogram showed moderate calibration, with a c-index of 0.709 in the derivation set and 0.712 in the validation set.

CONCLUSIONS

A nomogram based on sex, age, and number of synchronous lesions at the time of surgery has the ability to predict postoperative adenoma-free survival.

Multi-state relative survival modelling of colorectal cancer progression and mortality

Accurate identification of factors associated with progression of colorectal cancer remains a challenge. In particular, it is unclear which statistical methods are most suitable to separate the effects of putative prognostic factors on cancer progression vs cancer-specific and other cause mortality. To address these challenges, we analyzed 10 year follow-up data for patients who underwent curative surgery for colorectal cancer in 1985-2000. Separate analyses were performed in two French cancer registries. Results of three multivariable models were compared: Cox model with recurrence as a time-dependent variable, and two multi-state models, which separated prognostic factor effects on recurrence vs death, with or without recurrence. Conventional multi-state model analyzed all-cause mortality while new relative survival multi-state model focused on cancer-specific mortality. Among the 2517 and 2677 patients in the two registries, about 50% died without a recurrence, and 28% had a recurrence, of whom almost 90% died. In both multi-state models men had significantly increased risk of cancer recurrence in both registries (HR=0.79; 95% CI: 0.68-0.92 and HR=0.83; 95% CI: 0.71-0.96). However, the two multi-state models identified different prognostic factors for mortality without recurrence. In contrast to the conventional model, in the relative survival analyses gender had no independent association with cancer-specific mortality whereas patients diagnosed with stage III cancer had significantly higher risks in both registries (HR=1.67; 95% CI: 1.27-2.22 and HR=2.38; 95% CI: 1.29-3.27). In conclusion, relative survival multi-state model revealed that different factors may be associated with cancer recurrence vs cancer-specific mortality either after or without a recurrence.

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.

Current and emerging surveillance strategies to expand the window of opportunity for curative treatment after surgery in colorectal cancer

Colorectal cancer is the third most common cancer globally. At diagnosis, more than 70% of patients have nonmetastatic disease. Cure rates for early-stage colorectal cancer have improved with primary screening, improvements in surgical techniques and advances in adjuvant chemotherapy. Despite optimal primary treatment, 30-50% of these patients will still relapse. While death will result from widespread metastatic disease, patients with small volume oligometastatic disease are still considered curable with aggressive multimodality therapy. Hence, early detection of relapsed cancer when it is still amenable to resection expands the window of opportunity for cure. Here, the authors review the modalities currently employed in clinical practice and the evidence supporting intensive surveillance strategies. The authors also discuss ongoing clinical trials examining specific surveillance programs and emerging modalities that may be deployed in the future for early detection of metastatic disease.

Metachronous carcinomas in colorectum and its clinicopathological significance

PURPOSE

The study was designed to examine the significance of colorectal metachronous carcinoma in a large cohort of patients.

METHODS

Over a mean follow-up period of 10 years, the clinicopathological features, microsatellite instability (MSI) and clinical follow-up of 56 patients with metachronous colorectal carcinoma were analysed.

RESULTS

The prevalence of metachronous colorectal carcinoma was 2.1 %. The metachronous colorectal carcinomas appeared between 7 and 246 months (mean = 66 months) after surgical resection of the index colorectal carcinomas. Thirty-six per cent (n = 20) of the metachronous carcinoma occurred more than 5 years after the operation of the index carcinoma. Of the 56 patients, 20 % (n = 11) of the metachronous colorectal carcinomas were mucinous adenocarcinoma. Cancers detected in the secondary operations (metachronous colorectal carcinomas), when compared with the primary index cancers, were smaller, showed higher proportions of mucinous adenocarcinoma and more often located in the proximal colon. Patients with metachronous colorectal cancers had higher prevalence of mucinous adenocarcinoma, loss of staining for MSI markers and better survival rates than other patients with colorectal cancers.

CONCLUSIONS

Patients with metachronous colorectal carcinomas have characteristic features, and attention to these features is important for better management of this group of cancer.

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.

The incidence and risk factors of metachronous colorectal cancer: an indication for follow-up

BACKGROUND

Patients with colorectal cancer are at risk for developing metachronous colorectal cancer. The purpose of posttreatment surveillance is to detect and remove premalignant lesions to prevent metachronous colorectal cancer.

OBJECTIVE

The aim of this study was to investigate the incidence of and predictive factors for metachronous colorectal cancer in patients with newly diagnosed colorectal cancer.

DESIGN AND PATIENTS

The data on all patients with newly diagnosed colorectal cancer between 1995 and 2006 were obtained from the Rotterdam Cancer Registry in The Netherlands and studied for metachronous colorectal cancer.

MAIN OUTCOME MEASURES

The annual incidence rate and the standardized incidence ratios were calculated.

RESULTS

In total, colorectal cancer was diagnosed in 10,283 patients; there were 39,974 person-years of follow-up. The mean annual incidence rate of metachronous colorectal cancer was 314/100,000 person-years at risk during 10 years of follow-up, corresponding with a mean annual incidence of 0.3% and a cumulative incidence of 1.1% at 3 years, 2.0% at 6 years, and 3.1% at 10 years. The incidence of metachronous colorectal cancer after resection of a first colorectal cancer is significantly higher than the incidence of colorectal cancer in an age- and sex-matched general population (standardized incidence ratio 1.3, 95% CI 1.1-1.5). This difference is especially seen during the first 3 years after first colorectal cancer diagnosis (standardized incidence ratio 1.4, 95% CI 1.1-1.8). The presence of synchronous colorectal cancer was the only significant risk factor for developing metachronous colorectal cancer (relative risk 13.9, 95% CI 4.7-41.0).

CONCLUSIONS

Despite the availability of colonoscopy, metachronous colorectal cancer is still seen during follow-up in patients with colorectal cancer; the highest risk is during the first 3 years after initial diagnosis. For this reason, a follow-up colonoscopy is useful at a short-term interval after colorectal cancer diagnosis. The presence of synchronous colorectal cancer at the time of first colorectal cancer diagnosis is the only predictive risk factor for developing metachronous colorectal cancer. Tailored surveillance programs may be considered in patients with a diagnosis of synchronous tumors.

Post-treatment surveillance in colorectal cancer

BACKGROUND

Though the post treatment surveillance of patients with colorectal cancer (CRC) treated with curative intent is common practice, its value is controversial. In the absence of conclusive clinical data, various modalities for the routine follow-up of patients with CRC have been proposed. In practice, the guidelines across countries and regions differ and are influenced by different health care policies, resource availability and doubts about effectiveness of follow-up.

CONCLUSIONS

The results of metaanalyses of available clinical trials demonstrated a survival benefit of intensified monitoring, but the questions regarding the optimal frequency of visits and the examinations to be performed remain unanswered. Furthermore, intensive monitoring of CRC survivors may be difficult to be administrated, causes discomfort and morbidity to the patient and can have serious cost-implications to the healthcare system. However, as it seems from available data, a comprehensive surveillance program does not affect the quality of patients' life. Ongoing large prospective multi-institutional randomised trials might elucidate some of the crucial questions and existing dilemmas to establish adequate surveillance strategy for CRC patients.

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.

Clinical and pathological evaluation of patients with early and late recurrence of colorectal cancer

AIM

To compare the characteristics of primary cancer between patients with early recurrence and those with late recurrence of colorectal cancer.

METHODS

Overall 535 patients with primary colorectal cancer were reviewed and of these 130 patients with demonstrated recurrence were evaluated. Of the 130 patients, 91 had early recurrence (less than 2 years after surgery) and 39 had late recurrence (2 years or more after surgery). The clinical and pathological characteristics of primary cancer in these two groups were compared.

RESULTS

The rate of late recurrence was 30% of total recurrences (39/130). On average, patients with early recurrence were younger than patients with late recurrence (mean age 48 vs 54 years, p = 0.027). Adjacent organ involvement and Dukes stage C was more prevalent in the early recurrence group than in the late group. The liver was the main site of distant recurrence in the early recurrence group (64% of distant recurrences), whereas bone and peritoneum were the most frequent sites of metastases in the late recurrence group (58%). In Dukes C colon cancer patients the disease-free interval was significantly longer in those who received both adjuvant therapies than in those who received either radiotherapy or chemotherapy or neither of them.

CONCLUSION

This study showed that factors such as primary clinical signs, stage of primary tumor, and adjacent organ involvement are significant with respect to the time for recurrence of colorectal cancer. It is important to take these characteristics into account in patient care management after curative resection for colorectal cancer.

Second primary colorectal cancers (SPCRCs): experiences from a large Australian Cancer Registry

BACKGROUND

We examined the rate of second primary colorectal cancer (SPCRC) in a cohort of 29 471 patients first diagnosed with colorectal cancer (CRC) from 1987 to 1996, in New South Wales (NSW), Australia.

METHODS

The 5-year age group, date and site of first and subsequent CRC diagnoses as well as death dates were obtained from the NSW Central Cancer Registry. The time to SPCRC and standardised incidence ratios (SIRs) were generated.

RESULTS

Six hundred and sixty patients (2.1%) developed SPCRCs and the cumulative incidence at 18 years was 5.5%, 95% confidence interval (CI) 4.9% to 6.3%. The risk of SPCRC was increased in patients with a CRC history compared with the general population (SIR = 1.5, 95% CI 1.4-1.6) and inversely related to age at first diagnosis (30-49 years, SIR = 5.1, 95% CI 3.6-7.1 versus >/=80 years, SIR = 1.1, 95% CI 0.9-1.4). The excess absolute risk of SPCRC was greater for females aged 50-69 years at first diagnosis than for males in the same age group. SPCRC was also increased in individuals with right-sided first primaries (SIR = 2.0, 95% CI 1.6-2.4).

CONCLUSIONS

The SPCRC rate was increased during the first 5 years after first diagnosis but remained increased for up to 10 years in females, in patients with right-sided cancers and in patients <60 years at first diagnosis. These findings support active surveillance up to 10 years in these risk groups.

Four percent of patients undergoing colorectal cancer surgery may have synchronous appendiceal neoplasia

PURPOSE

An individual with colorectal cancer has a 3 percent risk of synchronous colonic neoplasia and further 2 to 3 percent risk of metachronous cancer, a risk that has prompted colonic surveillance. The appendix has a similar mucosal pattern to the colon and it has been hypothesized that appendicular adenocarcinoma may account for 1 percent of all colorectal malignancies. A special interest of the senior author in appendiceal and rectal cancer has prompted routine removal of the appendix in all cases undergoing surgery for colorectal cancer.

METHODS

Consecutive patients undergoing left colectomy or anterior resection for colorectal cancer had coincidental appendectomy with the specimen pathologically analyzed. A retrospective review of the case notes and histopathology was performed. Data also were collected for patients who had right hemicolectomy for colonic carcinoma.

RESULTS

In total, 169 patients under the care of a single surgeon had colorectal cancer resection between April 2002 and April 2005: 63 patients had right hemicolectomy, 29 had left hemicolectomy, and 77 had rectal cancer resection. Seven of 169 appendices had abnormalities: 3 mucinous cystadenomas, 2 cystadenocarcinomas, 1 carcinoid tumor, and 1 villous adenoma.

CONCLUSIONS

Patients having colorectal cancer resection for adenocarcinoma should have appendicectomy performed. Synchronous pathology was found in 4.1 percent in this series. Metachronous neoplasia is a risk in the retained appendix in patients with colorectal cancer. Routine postoperative surveillance cannot assess the appendiceal mucosa, so there is little justification for not taking the opportunity to eliminate the possibility of future appendicitis or neoplasia.

Metachronous colorectal cancer: necessity of post-operative colonoscopic surveillance

BACKGROUND AND AIMS

The aim of this study was to identify the occurrence and analyze the characteristics of metachronous colorectal cancers, and to compare the characteristics of these cases (index tumor) with the control group to find any predicting factor that may influence the occurrence of metachronous cancer.

PATIENTS AND METHODS

The database of colorectal cancer in the Veterans General Hospital-Taipei, from January 1981 to September 2001 was reviewed. In total, 3,846 cases of adenocarcinoma of the colon and rectum, which received curative resection during this period, were found. The criteria of metachronous cancer were: occurrence more than 12 months after curative surgery; with pre-operative complete colonoscopy or one negative post-operative colonoscopic follow-up to rule out synchronous tumor; tumor arising from mucosa at a site other than anastomosis. The age, gender of the patients, the location, pathological characteristics of the metachronous tumors, occurrence of associated adenomas, the number of lesions, and the tumor stage were analyzed and compared with the control group.

RESULTS

In total, 43 cases of metachronous cancer were identified, giving an annual incidence of 0.18%. The distribution of the location of the index tumor of metachronous cases was predominantly left-sided, which was not different from that of the control group. The mean duration of occurrence of metachronous cancer after the primary operation was 71+/-46.6 months. The association of adenomas had no relationship with the occurrence of the metachronous cancer. No significant predicting factors for the development of metachronous tumors were found.

CONCLUSION

Lifelong regular post-operative colonoscopic surveillance is essential for colorectal cancer patients.

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.

Follow-up of patients with curatively resected colorectal cancer: a practice guideline

BACKGROUND

A systematic review was conducted to evaluate the literature regarding the impact of follow-up on colorectal cancer patient survival and, in a second phase, recommendations were developed.

METHODS

The MEDLINE, CANCERLIT, and Cochrane Library databases, and abstracts published in the 1997 to 2002 proceedings of the annual meeting of the American Society of Clinical Oncology were systematically searched for evidence. Study selection was limited to randomized trials and meta-analyses that examined different programs of follow-up after curative resection of colorectal cancer where five-year overall survival was reported. External review by Ontario practitioners was obtained through a mailed survey. Final approval of the practice guideline report was obtained from the Practice Guidelines Coordinating Committee.

RESULTS

Six randomized trials and two published meta-analyses of follow-up were obtained. Of six randomized trials comparing one follow-up program to a more intense program, only two individual trials detected a statistically significant survival benefit favouring the more intense follow-up program. Pooling of all six randomized trials demonstrated a significant improvement in survival favouring more intense follow-up (Relative Risk Ratio 0.80 (95%CI, 0.70 to 0.91; p = 0.0008). Although the rate of recurrence was similar in both of the follow-up groups compared, asymptomatic recurrences and re-operations for cure of recurrences were more common in patients with more intensive follow-up. Trials including CEA monitoring and liver imaging also had significant results, whereas trials not including these tests did not.

CONCLUSION

Follow-up programs for patients with curatively resected colorectal cancer do improve survival. These follow-up programs include frequent visits and performance of blood CEA, chest x-rays, liver imaging and colonoscopy, however, it is not clear which tests or frequency of visits is optimal. There is a suggestion that improved survival is due to diagnosis of recurrence at an earlier, asymptomatic stage which allows for more curative resection of recurrence. Based on this evidence and consideration of the biology of colorectal cancer and present practices, a guideline was developed. Patients should be made aware of the risk of disease recurrence or second bowel cancer, the potential benefits of follow-up and the uncertainties requiring further clinical trials. For patients at high-risk of recurrence (stages IIb and III) clinical assessment is recommended when symptoms occur or at least every 6 months the first 3 years and yearly for at least 5 years. At the time of those visits, patients may have blood CEA, chest x-ray and liver imaging. For patients at lower risk of recurrence (stages I and Ia) or those with co-morbidities impairing future surgery, only visits yearly or when symptoms occur. All patients should have a colonoscopy before or within 6 months of initial surgery, and repeated yearly if villous or tubular adenomas >1 cm are found; otherwise repeat every 3 to 5 years. All patients having recurrences should be assessed by a multidisciplinary team in a cancer centre.

Colonoscopic surveillance after curative colorectal resection: results of an empirical surveillance programme

INTRODUCTION

Colonoscopic surveillance after colorectal cancer resection is widely practised despite little evidence that it improves survival. The optimum protocol for colonoscopic follow-up after colorectal cancer resection has not yet been elucidated. We audited the outcome of an empirical colonoscopic follow-up programme in a cohort of patients who underwent colorectal resection with a minimum of five years follow-up to establish patterns of metachronous neoplasia and suitable surveillance intervals.

METHODS

The colonoscopic records, biopsy results and follow-up details of patients diagnosed with colorectal cancer between June 1990 and June 1996 were reviewed. The number and type of metachronous neoplastic lesions diagnosed was recorded. Rates of development of new neoplasms were estimated by calculating the time from operation to their first discovery. Factors predictive of further development of polyps or cancer were sought. Results were compared to published reports of intensive follow-up programmes.

RESULTS

Seven hundred and ninety-eight patients underwent colorectal resection with curative intent during the study period. 226 patients had one or more follow-up colonoscopies (mean time post resection 48.8 months). In total 352 colonoscopies, encompassing 1437 patient years of surveillance, were performed. Nine metachronous cancers in eight patients, five of which were asymptomatic were diagnosed by colonoscopy at a mean of 63 months. Three asymptomatic recurrences were diagnosed but all were inoperable. 70 (31%) patients had adenomatous polyps diagnosed after a mean time from operation of 34 months for simple adenomatous polyps and 21 months for those with advanced features. Patients with multiple polyps or advanced polyps at the initial colonoscopy were more likely to form subsequent polyps. Only 5.8% of patients with a single adenoma or a normal colon formed an advanced adenoma over the next 36 months of surveillance.

CONCLUSION

The results of an empirical colonoscopic follow-up programme compared favourably to the results of the intensive programmes reported in the literature. Most patients are at very low risk of developing significant colonic pathology over the first five years after resection. Colonoscopic surveillance intervals need not be less than five years unless the patient has multiple adenomas or advanced adenomas at the first colonoscopy. Three yearly surveillance intervals are most probably adequate in these individuals.

A novel indicator for surveillance colonoscopy following colorectal cancer resection

INTRODUCTION

Current surveillance for recurrent intraluminal or metachronous colorectal cancer following resection is largely undertaken by colonoscopic examination of the remaining colon. The burden on colonoscopic services is high and the procedure is expensive. Immunological faecal occult blood testing (FOBT) is a sensitive and specific test for detecting colorectal cancer, and may fine tune the need for timely surveillance colonoscopy.

METHODS

Consecutive patients due for surveillance colonoscopy following colonic resection for cancer were prospectively studied. Each patient had a single faecal sample obtained at per rectal examination on a gloved examining finger. This was subjected to immunological FOBT in the clinic, and patients were categorized as FOBT positive or negative, according to the result. Colonoscopy as well as ultrasound or CT of the liver were performed within eight weeks of FOBT.

RESULTS

Six hundred and eleven patients had both FOBT and colonoscopy. Fifty-nine (13.6%) were categorized as FOBT-positive. Of these, nine had biopsy-proven recurrent or metachronous cancer, 12 patients had one, or more adenomatous polyps, one patient had radiation proctitis and two patients had pan-colonic mucositis following chemotherapy. In the remaining 552 FOBT-negative patients, no cancers were found. Thirty-eight patients had polyps that were removed. The sensitivity and specificity for detecting cancer by immunological FOBT was 100% sensitivity for detecting adenomatous polyps was 24% but specificity was 93%.

CONCLUSION

The immunological faecal occult blood test provides sensitive detection of metachronous and recurrent cancer in postoperative surveillance. Routine application may be used to reduce the frequency of colonoscopic surveillance, as a negative FOBT may be taken as a sign that colonoscopy may be deferred safely.

[Colonoscopic follow-up of patients undergoing curative resection of colorectal cancer]

AIM

To investigate the role of colonoscopy in the follow-up of patients undergoing curative resection of colorectal cancer.

MATERIAL AND METHODS

A prospective study was performed of 102 patients with colorectal cancer who underwent surgery with curative intention. Postoperative colonoscopic follow-up was a minimum of 5 years.

RESULTS

There were 62 males and 40 females. The mean duration of follow-up was 73.4 months. Synchronous polyps were found in 44.1% (114 in 45 patients) and metachronous polyps in 33.4% (64 in 34 patients). Synchronous carcinoma was detected in 7.8% (9 in 8 patients), metachronous carcinoma in 1.9% (2 in 2 patients) and suture recurrence in 4.9% (5 in 5 patients). Metachronous polyps developed in 55.5% of the patients with synchronous polyps and in only 15.8% of those with no synchronous polyps (p < 0.00005); the odds ratio was 6.67. Colonoscopy diagnosed 92 synchronous polyps and 64 metachronous polyps; of these, 34 were found to be significant(in 22 patients). Colonoscopy diagnosed 5 synchronous carcinomas; in 3 of these (polyps with non-invasive carcinoma) polypectomy constituted definitive therapy and in the remaining 2, curative resection was achieved. Colonoscopy diagnosed 2 stage C2 metachronous carcinomas at 63 and 94 months. Curative resection was achieved in both cases. Colonoscopic follow-up diagnosed 2 suture recurrences and resection was potentially curative.

CONCLUSIONS

Colonoscopy was found to play an essential role in 30% of the patients. The technique allowed the early diagnosis of synchronous carcinomas and curative treatment of metachronous carcinomas and demonstrated that the presence of synchronous polyps increases the risk of developing metachronous polyps.

Colonic screening and surveillance

Screening for colorectal cancer has not obtained worldwide acceptance in spite of its proven survival benefit for average-risk persons and some high-risk groups. The incidence of and mortality from colorectal cancer are worrying in Europe as well as in the USA, Australia and Japan. The best evidence-based studies are those published on screening using faecal occult blood tests, endoscopic methods and different tumour markers having been evaluated to a lesser degree. Feasibility studies are necessary before massive screening can be undertaken because the results obtained from randomized studies may not be reproduced to a satisfactory degree in average- as well as high-risk populations. Primary prevention by dietary intervention and drugs has been studied in great detail, so far without any major breakthrough. This chapter will address different screening methods in populations with a varying risk of colorectal cancer, together with providing a short review of prevention and intervention strategies.

Cytological and immunocytochemical evaluation of thyroid and breast masses in patients with a previous neoplasm: case reports

The diagnosis of secondary tumours represents one of the most important fields in the application of fine needle aspiration cytology (FNAC). We studied two patients, one with a history of breast cancer and one with a previous tumour of the thyroid, who showed a second mass, in the thyroid and in the breast, respectively, during follow up. The aim of our study was to evaluate if cytology, performed on FNAC smears, may distinguish a metastatic lesion from a second primary tumour, or if further immunocytochemistry should be performed. Our data demonstrate that, while cytology may be indicative of a second primary tumour, the histotype should be confirmed by immunocytochemical staining.

Metachronous colorectal cancers

BACKGROUND

Up to 9 per cent of patients who undergo resection for colorectal cancer develop metachronous cancers. There is no consensus on the detection and management of such cancers.

METHODS

The literature was reviewed exhaustively regarding the incidence, clinical characteristics, detection, treatment and molecular genetics of metachronous colorectal cancers. This was based on a Medline search from 1966 to December 1997 for articles on metachronous colorectal cancers. A manual search was also performed on references quoted in these articles. All publications relevant to this study were included.

RESULTS

Although the underlying causes for metachronous colorectal cancers are yet to be elucidated, risk factors for the disease have been identified. These include the presence of synchronous polyps or cancers, a history of metachronous cancers, and hereditary non-polyposis colorectal cancer (HNPCC).

CONCLUSION

Preoperative colonoscopy and postoperative colonoscopic surveillance are essential in identifying patients at risk of metachronous colorectal cancer. A total colectomy and ileorectal anastomosis should be considered for some patients, certainly for those with HNPCC.

Incidence of DNA replication errors in patients with multiple primary cancers

PURPOSE

Multiple primary cancers are a feature of hereditary nonpolyposis colorectal cancer in which defects in DNA repair mechanisms result in accumulation of replication errors within tumor DNA. We assessed replication error incidence in multiple primary cancer patients who may have similar genetic defects.

METHODS

DNA was obtained from 69 patients from the Yorkshire region who had developed colorectal cancer and one other primary tumor from the hereditary nonpolyposis colorectal cancer tumor spectrum (28 colorectal, 12 stomach, 15 ovary, and 14 uterus). DNA was also obtained from 86 sporadic, single primary cancer patients attending a colorectal cancer clinic. Replication error status was assessed at five microsatellite loci using fluorescent polymerase chain reaction and computer-assisted analysis.

RESULTS

The replication error phenotype was observed in 7 of 86 (8 percent) of the sporadic single primary patients. This compared with 23 of 69 (33 percent) of the multiple primary group (P < 0.001). Replication error was also observed more frequently in each subgroup. Even excluding patients from families meeting the Amsterdam criteria (likely to be hereditary nonpolyposis colorectal cancer and have the replication error phenotype), this increased frequency remained in both the multiple primary group (P < 0.005) and multiple colorectal and colorectal/uterine subgroups (P < 0.001).

CONCLUSIONS

Results suggest that genetic instability plays an important role in development of multiple primary cancers, particularly from certain cancer subsets. Testing for replication errors may be an appropriate way of identifying individuals at risk of multiple primary cancers.

Colorectal cancer screening by general practitioners: comparison with national guidelines

OBJECTIVE

To determine whether general practitioners (GPs) had received Australian guidelines on early detection, screening and surveillance for colorectal cancer or rectal bleeding, and whether their reported practice conformed with these guidelines.

DESIGN

Cross-sectional postal survey of self-reported practice.

PARTICIPANTS AND SETTING

213 GPs in practice in the southern metropolitan area of Perth, Western Australia, were randomly selected from the Fremantle Regional Division of General Practice database and surveyed in March 1997.

RESULTS

Replies were received from 155 (73%) of the GPs, and 110 reported receiving guidelines (from the Australian Gastroenterology Institute [AGI], 44; Gut Foundation of Australia [GFA], 40; others, 6; and not specified, 20). GPs who reported receiving guidelines were significantly more likely to screen for colorectal cancer (99/110; 90%) than those who reported not receiving guidelines (33/45; 73%) (P = 0.008). The commonest method to investigate people with identifiable risk factors for colorectal cancer was colonoscopy. Reported screening frequencies in asymptomatic patients with above-average risk (family history of colorectal cancer or past history of adenomatous polyps or colorectal cancer) were significantly higher than recommended by AGI and GFA guidelines (P < 0.05). Up to 24% of GPs investigated altered bowel habit or bleeding per rectum with faecal occult blood testing.

CONCLUSIONS

Most GPs report having received guidelines. Reported screening frequency was higher than recommended for most above-average-risk patients, which will result in excessive consumption of resources without benefits for cancer prevention.

Hereditary non-polyposis colorectal cancer: clinical features and survival. Results from the Danish HNPCC register

BACKGROUND

Hereditary non-polyposis colorectal cancer (HNPCC) is a dominantly inherited syndrome characterized by the development of colorectal cancer (CRC) and other carcinomas. Our aim was to evaluate tumour parameters and survival in HNPCC.

METHODS

One hundred and eight Danish HNPCC patients were compared with 870 patients with sporadic colorectal cancer.

RESULTS

The median age at CRC diagnosis was 41 years in the HNPCC group. HNPCC patients had significantly more carcinomas located to the right colon (68% against 49% in controls), more synchromous tumours (7% versus 1%), more metachronous CRC after 10 years (29% versus 5%), more localized carcinomas (62% versus 39%), and significantly higher crude cumulative 5-year survival (56% versus 30%).

CONCLUSIONS

CRC in HNPCC behaves differently compared to sporadic cases concerning age of onset, frequency of multiple lesions, and location. The metastatic tendency is less than in sporadic CRC and the survival is better.

Characteristics of metachronous colorectal carcinoma occurring despite colonoscopic surveillance

PURPOSE

Metachronous colorectal cancer still occurs in a small percentage of patients, despite colonoscopic surveillance. Cancers in hereditary nonpolyposis colorectal cancer for which there is a high risk of metachronous cancer show distinctive DNA changes termed replication errors (RER+). Ten to 20 percent of sporadic colorectal cancers are also RER+. The aim of this study was to identify factors predictive of metachronous colorectal cancer, despite colonoscopic surveillance. Clinicopathologic characteristics and RER status of cancers were examined.

METHODS

Colorectal cancer patients, who entered into a surveillance program of being examined with colonoscopy within six months of surgery and then at intervals of three years thereafter, were reviewed. The 433 patients compliant with the protocol who had had more than one colonoscopy had been followed up for a mean of 3.8 +/- 2.2 years. DNA was extracted from archival paraffin-embedded cancer tissue for determination of RER status.

RESULTS

Ten cases of metachronous cancer were identified, giving a rate of 0.61 percent per year. The site of the index cancer in patients who later developed metachronous cancer was predominantly proximal (P = 0.0007), and these cancers were more likely to have mucinous histology (P < 0.0005). Three of 10 (30 percent) index cancers were RER+, which was not significantly different from unselected series of control colorectal cancers in which 20 of 108 (18.5 percent) were RER+.

DISCUSSION

This study documents the rate of metachronous cancer among patients compliant with a defined colonoscopic screening program and suggests that the risk is highest in patients with a proximal mucinous cancer. RER status does not appear to be a very strong predictive factor, and this study does not support its use as a guide to the frequency of surveillance colonoscopy. More data would be required to determine if RER positivity conferred a relative risk of 3.3 or less.

Colorectal cancer in familial adenomatous polyposis

PURPOSE

This study was performed to determine the relationship among surgical treatment, colorectal cancer, and outcome in patients with familial adenomatous polyposis (FAP).

METHODS

Records of 115 patients with FAP who underwent surgery at The Mount Sinai Medical Center between 1947 and 1994 were retrospectively reviewed. Patients without cancer were compared with those with colorectal cancer at initial surgery and with patients who developed rectal cancer following colectomy.

RESULTS

Thirty-one patients (27 percent) had colorectal cancer at the time of initial surgery (colon = 24; rectal = 7). Another 11 patients (26 percent) developed rectal cancer after colectomy with ileorectal anastomosis (IRA). Mean age of patients with colorectal cancer at initial surgery was significantly higher than those without cancer (P < 0.01). Patients who developed rectal cancer after IRA were significantly older than patients with colorectal cancer at initial surgery (P < 0.01). All patients with rectal cancer after IRA had advanced disease with either nodal or distant metastases at the time of diagnosis.

CONCLUSIONS

Colorectal cancer remains a major problem in the treatment of patients with FAP. Nearly one-fourth of these patients have colorectal cancer at initial operation, and one-fourth of patients with IRA develop rectal cancer after a mean follow-up of 13 years. Patients with rectal cancer following IRA are more likely to have advanced tumors than patients with colorectal cancer at initial operation. The high incidence and late stage of rectal cancer detected while under surveillance after IRA supports excision of the entire colorectal mucosa as the treatment of choice for most patients with FAP.

Screening for colorectal cancer, 1996

Screening average-risk people aged 55 to 70 years for colorectal cancer is now a public health priority in Australia. Pilot studies of faecal occult blood testing are required to find ways of achieving optimal compliance and cost efficiency in the Australian health care setting. Flexible sigmoidoscopy probably should be used as complementary screening but further trials are needed. High-risk groups (family history of colorectal cancer, or previous ulcerative colitis, adenomas or cancer) should already be in surveillance programs.

Colon surveillance after colorectal cancer surgery

PURPOSE

This study was performed to determine cost-effective colonoscopy guidelines for patients with prior colorectal adenocarcinoma.

METHOD

A retrospective review was performed of patients who had been treated for colorectal adenocarcinoma and later underwent follow-up colonoscopy from 1984 to 1994.

RESULTS

During this study period, 389 patients previously treated for colorectal adenocarcinoma underwent follow-up colonoscopy. All patients had perioperative colon evaluation for other neoplasms. Ages ranged from 26 to 89 (mean, 65.8) years, and 46.8 percent were female. Recurrent or metachronous cancer or a neoplastic polyp constituted a positive examination. Results of 389 first follow-up colonoscopies were compared with 259 second (66.6 percent), 165 third (42.4 percent), and 83 fourth (21.3 percent) follow-up examinations. Median interval between all colonoscopies was 13 months. Positive examination rates for the first two yearly examinations were 18.3 and 18.5 percent, respectively. Slightly lower, third-year and fourth-year positive examination rates were 16.4 and 14.5 percent, respectively. Four-year examinations yielded the following: first year--1 carcinoid, a new adenocarcinoma, and 100 polyps; second year--1 anastomotic recurrence and 68 polyps; third year --55 polyps; and fourth year--1 recurrent cancer and 17 polyps.

CONCLUSIONS

These data suggest that 1) annual follow-up colonoscopy for two years after colorectal cancer surgery is beneficial for detecting recurrent and metachronous neoplasms and 2) the interval between subsequent examinations may be increased depending on the result of the most recent examination.

Clinical characteristics of metachronous colorectal tumors

A cancer-registry-based study was conducted to investigate the survival patterns associated with metachronous colorectal tumors and to compare the survival of patients with single and metachronous colorectal tumors. The study included all 1,396 White patients with metachronous colorectal tumors diagnosed among 143,283 patients with primary colorectal tumors reported between 1973-1986 to the SEER program. The influence on survival of age at diagnosis, site of tumor and stage was evaluated by means of multivariate survival analysis, using Cox Proportional Hazards Models. Metachronous tumors developed more often following left-colon tumors. Stage distribution of the second tumors was better than that of single 47% of the second tumors were discovered in regionally-advanced or distant-metastatic stages. Survival from the second tumor diagnosed in the rectum was worse than that of a single tumor in the same stage and site. Only the stage of the second tumor was found to influence survival from metachronous tumors. The relatively high rate of diagnosis of advanced second colorectal tumors may reflect either improper follow-up after the diagnosis of the first tumor, or more aggressive biological characteristics of the second tumors.

Analysis of multiple primary cancers in a single institution

Records of 120 patients with two and 16 with three primary cancers were evaluated. There were 49 males and 71 females among the double primaries with ages ranging from 27-102 years (average 68 years at the time of fist cancer). Of 35 breast cancer patients 16 new primaries developed in the opposite breast and other sites including four colon, three lung, and three endometrium. Of 20 colon cancer patients second primaries occurred in 11 sites most commonly colon (four) and lung (three). The frequency of second primaries may be skewed by the fact that patients with lethal cancers did not live long enough to develop them. This is borne out by the fact that 74 of the 120 patients were alive at the time of the study, implying a highly favorable group of patients. The interval between primaries was longer in females than males (P < 0.05) and this difference disappeared when breast and endometrial cancer were eliminated. When age was evaluated as a factor younger patients appeared to have a longer interval between primaries (P = 0.24) and this became significant for breast patients under age 55 years (91 months vs. 36 months) (P < 0.05). The stage of the second breast primary bore no relationship to the interval between primaries.

Follow-up of patients with colorectal cancer. A meta-analysis

OBJECTIVE

The authors sought to determine whether intensive follow-up improves 5-year survival rates in patients with colorectal cancer who were operated on for cure.

SUMMARY BACKGROUND DATA

Intensive follow-up of patients with colorectal cancer is still controversial. The present uncertainty in regard to the value of intensive follow-up could be the result of the absence of prospective randomized studies comparing patients with and without follow-up.

METHODS

Studies comparing two follow-up programs of different intensities were identified in the medical literature and were aggregated in a meta-analysis using the "random effects method." Seven nonrandomized studies describing 3283 patients were analyzed.

RESULTS

Patients with intensive follow-up did have 9% better 5-year survival rates than did those with minimal or no follow-up, only when intensive follow-up included carcinoembryonic antigen (CEA) assays. In addition, more asymptomatic recurrences were detected and more recurrences were resected in patients with intensive follow-up.

CONCLUSIONS

This meta-analysis indicated that intensive follow-up using CEA assays can identify treatable recurrences at a relatively early stage. Treatment of these recurrences appears to be associated with improved 5-year survival rates. However, not all intensive follow-up strategies will be equally effective. Follow-up may yield the best results if diagnostic tests are used only to detect those recurrences that can be operated on with curative intent and when follow-up is "individualized," according to patient characteristics.