An evaluation of postoperative follow-up tests in colon cancer patients treated for cure

PRE- AND POSTOPERATIVE IMAGING METHODS IN COLORECTAL CANCER

INTRODUCTION

Among the screening tests for colorectal cancer, colonoscopy is currently considered the most sensitive and specific technique. However, computed tomography colonography (CTC), magnetic resonance imaging (MRI), and transrectal ultrasonography have gained significant ground in the clinical practice of pre-treatment, screening and, more recently, post-treatment and surgical evaluation.

OBJECTIVE

To demonstrate the high accuracy of CT and MRI for pre and postoperative colorectal cancer staging.

METHODS

Search and analysis of articles in Pubmed, Scielo, Capes Periodicals and American College of Radiology with headings "colorectal cancer" and "colonography". Weew selected 30 articles that contained radiological descriptions, management or statistical data related to this type of neoplasia. The criteria for radiological diagnosis were the American College of Radiology.

RESULTS

The great majority of patients with this subgroup of neoplasia is submitted to surgical procedures with the objective of cure or relief, except those with clinical contraindication. CTC colonography is not the most commonly used technique for screening; however, it is widely used for treatment planning, assessment of the abdomen for local complications or presence of metastasis, and post-surgical evaluation. MRI colonography is an alternative diagnostic method to CT, recommended by the American Society of Gastrointestinal Endoscopy. Although there are still no major studies on the use of MRI for screening, the high resolution examination has now shown good results for the American Joint Committee on Cancer TNM classification.

CONCLUSION

MRI and CT represent the best means for colorectal neoplasm staging. The use of these methods as screening tools becomes beneficial to decrease complications and discomfort related to colonoscopy.

Blood CEA levels for detecting recurrent colorectal cancer

BACKGROUND

Testing for carcino-embryonic antigen (CEA) in the blood is a recommended part of follow-up to detect recurrence of colorectal cancer following primary curative treatment. There is substantial clinical variation in the cut-off level applied to trigger further investigation.

OBJECTIVES

To determine the diagnostic performance of different blood CEA levels in identifying people with colorectal cancer recurrence in order to inform clinical practice.

SEARCH METHODS

We conducted all searches to January 29 2014. We applied no language limits to the searches, and translated non-English manuscripts. We searched for relevant reviews in the MEDLINE, EMBASE, MEDION and DARE databases. We searched for primary studies (including conference abstracts) in the Cochrane Central Register of Controlled Trials (CENTRAL), in MEDLINE, EMBASE, and the Science Citation Index & Conference Proceedings Citation Index - Science. We identified ongoing studies by searching WHO ICTRP and the ASCO meeting library.

SELECTION CRITERIA

We included cross-sectional diagnostic test accuracy studies, cohort studies, and randomised controlled trials (RCTs) of post-resection colorectal cancer follow-up that compared CEA to a reference standard. We included studies only if we could extract 2 x 2 accuracy data. We excluded case-control studies, as the ratio of cases to controls is determined by the study design, making the data unsuitable for assessing test accuracy.

DATA COLLECTION AND ANALYSIS

Two review authors (BDN, IP) assessed the quality of all articles independently, discussing any disagreements. Where we could not reach consensus, a third author (BS) acted as moderator. We assessed methodological quality against QUADAS-2 criteria. We extracted binary diagnostic accuracy data from all included studies as 2 x 2 tables. We conducted a bivariate meta-analysis. We used the xtmelogit command in Stata to produce the pooled estimates of sensitivity and specificity and we also produced hierarchical summary ROC plots.

MAIN RESULTS

In the 52 included studies, sensitivity ranged from 41% to 97% and specificity from 52% to 100%. In the seven studies reporting the impact of applying a threshold of 2.5 µg/L, pooled sensitivity was 82% (95% confidence interval (CI) 78% to 86%) and pooled specificity 80% (95% CI 59% to 92%). In the 23 studies reporting the impact of applying a threshold of 5 µg/L, pooled sensitivity was 71% (95% CI 64% to 76%) and pooled specificity 88% (95% CI 84% to 92%). In the seven studies reporting the impact of applying a threshold of 10 µg/L, pooled sensitivity was 68% (95% CI 53% to 79%) and pooled specificity 97% (95% CI 90% to 99%).

AUTHORS' CONCLUSIONS

CEA is insufficiently sensitive to be used alone, even with a low threshold. It is therefore essential to augment CEA monitoring with another diagnostic modality in order to avoid missed cases. Trying to improve sensitivity by adopting a low threshold is a poor strategy because of the high numbers of false alarms generated. We therefore recommend monitoring for colorectal cancer recurrence with more than one diagnostic modality but applying the highest CEA cut-off assessed (10 µg/L).

Surveillance and Survivorship after Treatment for Colon Cancer

Colorectal cancer is the third most common cancer diagnosed in the United States. Majority of patients have localized disease that is amenable to curative resection. Disease recurrence remains a major concern after resection. In addition, patients are at an increased risk for developing a second or metachronous colon cancer. The principal goal of surveillance following treatment of colon cancer is to improve disease-free and overall survival. Survivorship is a distinct phase following surveillance to help improve quality of life and promote longevity.

Follow-up after curative resection of colorectal cancer

Of the 13.7 million cancer survivors living in the United States as of January 2012, 1.2 million, or 9 %, were colorectal cancer (CRC) survivors. Determining an optimal surveillance for CRC survivors is necessary because of the significant burden follow-up poses to patients, physicians, and the health care system. Currently, there is no consensus regarding optimal follow-up in CRC patients. Current literature and published guidelines related to CRC follow-up were reviewed to examine the evidence for the surveillance strategies and specific tools demonstrated to improve outcome after curative CRC resection. An intensive surveillance strategy results in increased identification of recurrences amenable to curative resection but does not result in reduced overall or CRC-specific mortality. Patients most likely to benefit from surveillance include younger patients, those with earlier tumors, locoregional recurrences, longer time to recurrence, lower carcinoembryonic antigen (CEA) levels before reoperation, and those with isolated recurrence. Complete resection of recurrence is the only factor consistently associated with improved survival. CEA, colonoscopy, and liver-focused imaging surveillance appear to have the greatest impact on mortality after curative CRC resection. A CRC surveillance strategy is recommended that includes tumor risk stratification, that provides a focus on identifying recurrences amenable to complete resection, and that utilizes those modalities demonstrated to be most effective at improving outcome after CRC resection.

Colorectal cancer follow-up: Useful or useless?

Follow-up of surgically treated colorectal cancer patients is not supported by objectively certain data. Despite the thousands of investigations reported in the scientific literature, only six randomized prospective studies and two meta-analysis of randomized studies provide data suggesting clear conclusions. Our review of the literature revealed that intensive colorectal follow-up should be performed even if the long-term survival benefit is small. The timing and investigations conducted in follow-ups diverge. The inconsistency of follow-ups is revealed by the fact that the leading USA and European societies propose different guidelines. One datum that the literature agrees on is that pancolonoscopy performed at 3-5 year intervals in colorectal cancer surgery patients supports diagnosis of adenomatous polyps and metachronous cancers. Cost analysis have shown that intensive follow-up would certainly exceed the cut-off point level set for every additional year of good quality of life.

Follow-up of patients with colorectal cancer: the evidence is in favour but we are still in need of a protocol

The prevalence of colorectal cancer is high in the western world and follow-up after treatment of the primary tumour is claimed to consume resources that could be used in improving screening and early diagnosis. Although some patients with recurrent disease can be treated successfully there has been a debate on whether an overall improvement in survival is achieved by follow-up. There is no agreement on a follow-up protocol of investigations. A review via a Medline search of all published studies and reports on the issue of follow-up of colorectal cancer dated from 1975-2006. We examined retrospective and prospective studies, randomised controlled trials, and meta-analyses attempting to identify the optimum follow-up protocol. There is widespread diversity of follow-up policies for colorectal cancer. Follow-up of colorectal cancer does not have a negative impact on Quality of life. There is no evidence that annual colonoscopy provides any survival advantage. It has been shown that intensive follow-up with frequent carcinoembryonic antigen measurement has a survival advantage and is cost-efficient. Similar evidence seems to be gathering about liver imaging with CT scan although it is less conclusive.

Assessment of risk-independent follow-up to detect asymptomatic recurrence after curative resection of colorectal cancer

BACKGROUND AND AIMS

Colorectal cancer is one of the leading causes of cancer death. We analyzed the value of standardized, risk-independent postoperative surveillance.

MATERIALS AND METHODS

Between 1995 and 2001, 564 patients with colorectal cancer underwent standardized oncologic resection. One hundred thirty-four were unable to take part in the surveillance program, while 430 patients were grouped as follows: group I (n=272, risk-independent follow-up), group II (n=113, follow-up at other departments), and group III (n=45, no follow-up).

RESULTS

The 5-year cancer-specific survival rate for UICC III and IV was significantly higher in group I (87%) as compared to group II (35%). In group I, the 5-year disease-free survival rate was 70%. Cancer recurrence occurred at mean 17 (+/-12) months after colorectal resection and yielded a 5-year survival rate of 63%. Reresection was performed in 17 (35%) patients, of whom ten remained disease-free (5-year survival rate, 91%). The money spent for one patient's 5-year follow-up was 1665.

CONCLUSIONS

A standardized, risk-independent follow-up program allows early diagnosis of asymptomatic recurrence of colorectal cancer. Reresection improves the 5-year survival rate in this setting.

Colorectal cancer follow-up in 2005

The main goal in monitoring patients after the treatment of colorectal cancer is to improve survival through the early identification and treatment of metastatic or locally recurrent disease. Although the results of several randomized, controlled trials have identified a survival benefit associated with careful follow-up, specific testing strategies to maximize survival while minimizing cost and patient inconvenience have not been identified. There is, therefore, great variability in the types, number, and frequency of tests ordered to follow these patients. This article reviews the level-I data avail-able regarding the efficacy of follow-up, the specific tests commonly used, and issues of costs and patient satisfaction, and provides a summary of the available societal guidelines concerning colorectal cancer follow-up.

Asociación entre la inestabilidad de microsatélites y las características clínicas y anatomopatológicas en pacientes con cáncer de colon esporádico

BACKGROUND AND OBJECTIVE

Currently, colon cancer is a leading cause of cancer death world-wide. It progresses according to three molecular pathways, named suppressor, mutador and methylator. Microsatellite instability is a hallmark of the lack of reparation, of DNA mismatches and it characterizes a subset of colon tumors (unstable tumors, MSI). MSI-H patients (high degree of microsatellite instability) seem to share clinico-pathological differences with MSS (microsatellite stable) and MSI-L (low degree of microsatellite instability) patients. In this study, associations between high degree of microsatellite instability and pathological (location, mucinous content, differentiation grade, stages T3N0, stages II and III) and clinical features (response to chemotherapy, disease-free survival and overall survival) were evaluated.

PATIENTS AND METHOD

117 patients with sporadic colon cancer were classified into two populations (MSS/MSI-L and MSI-H) by using PCR and electrophoresis of seven microsatellites, according to the National Cancer Institute recommendations.

RESULTS

MSI-H tumors tended to be located in the right colon (p = 0.022) and were of mucinous histologic type (p = 0.04). No differences in disease-free survival and overall survival between group of stage II and III patients with MSS/ MSI-L and corresponding ones with MSI-H colon cancer were found (p = 0.54, p = 0.37, respectively). Conversely, MSI-H patients with stage II colon cancer had a favourable prognosis (p = 0.027). Nevertheless, response to 5-fluorouracil (5-FU) and leucovorin was similar in MSS/ MSI-L and MSI-H groups (p = 0.38).

CONCLUSIONS

MSI-H patients are characterized by certain pathological features; those MSI-H patients with a stage II seem to have a better prognosis than MSS/ MSI-L patients.

Adjuvant therapy of colon cancer

Although surgical resection is still the only curative maneuver in the treatment of colon cancer, efforts of the past decades have proved that systemic chemotherapy in the adjuvant setting definitely improves the curative rate for those patients with localized colon cancer. The combination of the 5-fluorouracil (5-FU) and leucovorin (LV) remains the reference treatment. However, the advantage of infusional 5-FU/LV with oxaliplatin (FOLFOX) as adjuvant treatment may change the paradigm soon. Capecitabine may be considered as an alternative to 5-FU/LV in the adjuvant therapy of stage III colon cancer. The clinical benefit of adjuvant chemotherapy for localized node negative (stage II) disease is definite but small, even though there is yet no universal consensus. Novel molecular and biologic-oriented agents are being studied. Further analysis and definition of prognostic and predictive markers may allow future adjuvant therapy to be individualized.

Chemotherapy for colorectal cancer

With effective chemotherapy as adjuvant treatment, the survival benefit is clearly achieved for certain (stage III) colorectal cancer patients, though there still exist many unsettled issues including the controversies in the treatment of stage II disease. Advances in the development of a new generation of cytotoxic agents in the past several years have allowed us to move forward from the "fluorouracil-only era" in the treatment of advanced/metastatic colorectal cancer. It is still not very clear how best to minimize toxicity without compromising efficacy of the combination therapy with newer agents, or how to maximize the benefit of chemotherapy (concurrent versus sequential). There are many current ongoing clinical trials designed to address these issues. With better understanding of the signal transduction and molecular biology characteristics of colorectal cancer, and the development of biologic and molecular target agents, the outcomes of patients with colorectal cancer will be improved further. Future clinical trials should be focused on optimizing and individualizing therapy for patients based on their molecular profiles to achieve maximal clinical benefit.

Results of long-term follow-up after curative resection of Dukes A colorectal cancer

Patients with Dukes A (UICC I) colorectal cancer have a good prognosis after curative resection. It is not known, however, if the outcome is significantly different for UICC Ia and Ib patients or if patients with reduced risks of recurrences can be identified early after surgery. This is of interest, as it would permit a more cost-effective, patient-oriented, and tumor stage-oriented follow-up program. To study these questions, a prospective follow-up database, including 1375 patients after curative resection of colorectal cancer, was analyzed. A total of 296 patients with Dukes A colorectal cancer with a median follow-up of 44 months were studied. Perioperative and follow-up mortality rates were 3% and 14%, respectively. Recurrent disease developed in 10% of Dukes A patients after a disease-free interval of 16 months. Significantly more patients suffering from pT2 (UICC Ib) cancer had recurrent disease than patients with pT1 (UICC Ia) cancer (13% vs. 4%; p <0.05). Preoperative CEA levels in patients with recurrent disease were significantly higher than in long-term disease-free patients (5.3 +/- 1.8 vs. 3.5 +/- 0.6 ng/ml; p <0.05). Curative resection of recurrent disease was achieved in 38% of the patients with recurrences (4% of all patients). Survival analysis showed significantly better survival in patients with Dukes A cancer than in those at higher tumor stages (log rank, <0.0001), and only 39% of all Dukes A patients who died during follow-up had recurrent disease. Dukes A (UICC Ia and Ib) colorectal cancer was diagnosed in 22% of our patients treated for cure, and long-term survival was 86%. There were significantly fewer cases of recurrent disease after curative resection of UICC Ia (pT1N0M0) cancer, so we propose a novel, less intensive follow-up regimen for these patients, leading to a more cost-effective, patient-oriented, and tumor stage-oriented follow-up program.

Follow-up of patients with colorectal cancer: numbers needed to test and treat

Follow-up after curative treatment of patients with colorectal cancer has as its main aims the quality assessment of the treatment given, patient support, and improved outcome by the early detection and treatment of cancer recurrence. How often, and to what extent, the final aim, improved survival, is indeed realised is so far unclear. A literature search was performed to provide quantitative estimates for the main determinants of the effectiveness of the follow-up. Data were extracted from a total of 267 articles and databases, and were aggregated using modern meta-analytic methods. In order to provide one more colorectal cancer patient with long-term survival through follow-up, 360 positive follow-up tests and 11 operations for colorectal cancer recurrence are needed. In the remaining 359 tests and 10 operations, either no gains are achieved or harm is done. As the third aim of colorectal cancer follow-up, improved survival, is realised in only few patients, follow-up should focus less on diagnosis and treatment of recurrences. It should be of limited intensity and duration (3 years), and the search for preclinical cancer recurrence should primarily be performed by carcino-embryonic antigen (CEA) testing and ultrasound (US). The focus of colorectal cancer follow-up should shift from the early detection of recurrence towards quality assessment and patient support. As support that is as good or even better can be provided by a patient's general practitioner (GP) or by specialised nursing personnel, there is no need for routine follow-up to be performed by the surgeon.

Value and cost of follow-up after adjuvant treatment of patients with Dukes' C colonic cancer

BACKGROUND

The clinical value and costs of different diagnostic tools used to identify potentially curable recurrent disease in patients treated adjuvantly for curatively resected Dukes' C colonic cancer were examined.

METHODS

The study group comprised 496 patients treated with chemotherapy over a 1-year interval. Follow-up consisted of interim history, physical examination, liver ultrasonography or computed tomography (CT), measurement of carcinoembryonic antigen (CEA) levels, chest radiography and colonoscopy.

RESULTS

Two hundred and thirteen patients had recurrent disease (median follow-up 43 months). Forty-two patients with recurrence (20 per cent) were treated with curative intent (median survival 38 months; 5-year survival rate 40 per cent). Recurrence was identified by liver ultrasonography or CT (n = 14), evaluation of symptoms (n = 12), colonoscopy (n = 8), CEA measurement (n = 3), chest radiography (n = 2), physical examination (n = 1) and other modalities in two patients. The mean cost of diagnostic procedures per curative resected recurrence for patients amenable to salvage surgery was US$9011. Of all treatable recurrences, 12 of 42 were identified by evaluation of symptoms only. Ultrasonography and colonoscopy identified 22 recurrences at a cost of US$11 790 per patient, while routine follow-up by CEA measurement, chest radiography and physical examination identified a further six at a cost of US$19 850 per patient.

CONCLUSION

Potentially curable recurrences were detected primarily by liver imaging and colonoscopy. The yield of CEA measurement, chest radiography and physical examination was relatively low; such methods were expensive and should not be recommended in the routine follow-up of these patients.

Colorectal cancer follow-up: a reassessment of empirical evidence on effectiveness

Colorectal cancer is an important cause of death in the Western world, with a propensity of cancer recurrence even after resection with curative intent. Active follow-up has been advocated as a means to detect cancer recurrence at an earlier stage and thereby improve the survival of colorectal cancer patients. The present study assesses published evidence on the effectiveness of follow-up. Articles were obtained from a 20-year Medline search and from cross-references between articles. Articles were included, scored for quality, and extracted by explicit criteria. Regression analysis and chi-squared analysis was performed to assess (1) whether detection of recurrence at earlier asymptomatic disease stage leads to better post-treatment prognosis, and (2) whether active follow-up does improve overall (quality adjusted) survival, as compared to symptom-guided care only. The relationship between disease stage of recurrence (symptoms, number and size) and survival was analysed from 42 articles, 10 of which provided adequate data. Absence of symptoms and small number of recurrence were significantly related to better survival, smaller size insignificantly so. The potential of active follow-up seemed related to a marginally better outcome, larger gains being found in lower quality studies. Available data do suggest that survival gains vary between 0.5 and 2%, 1% seeming to be a best estimate of overall survival gain. Neither the notion that earlier detection of recurrences does significantly improve outcome, nor the hope that active follow-up provides a statistically and clinically significant gain in (quality adjusted) survival, are so far supported by adequate evidence. Colorectal cancer follow-up still fails to meet the criteria for evidence based medicine.

The normal CT appearances of the second carina and bronchial stump after left upper lobectomy

We retrospectively evaluated the computed tomography (CT) appearance of the bronchial stump and second carina (left upper lobe spur) after left upper lobectomy. There were 69 CT examinations in 38 patients; all were free of recurrent or metastatic disease. The spur was graded as a) sharp (wedge-shaped tip configuration with <90 degrees angulation), b) lobulated (bulbous tip with <90 degrees angulation), or c) widened (>90 degrees angulation regardless of tip configuration). The bronchial stump was evaluated for the presence or absence of soft tissue in proximity to the surgical staples. The spur had a sharp appearance in 33 of 38 patients (87%) and was lobulated in 5 of 38 (13%). No patient had soft tissue at the bronchial stump. Serial examinations showed no change in the appearance of either structure. The spur remains sharp after left upper lobectomy in most patients; lobulation occurs in 13%. No changes occur over time. Interval change, widening of the spur, or soft tissue at the bronchial stump may suggest abnormality. Knowledge of normal and potentially abnormal appearances is essential to proper CT interpretation, particularly in the setting of postoperative surveillance for recurrent or metastatic disease.

Computerized nuclear morphometry is a useful technique for evaluating the high metastatic potential of colorectal adenocarcinoma

BACKGROUND

Nuclear profiles have been reported to be useful prognostic predictors in various cancers. Data from computerized morphometry are objective and are quickly obtained by conventional microscopic analysis. However, this image analysis of nuclear features has been only rarely applied to investigations of colorectal adenocarcinoma. The aim of this study was to evaluate the correlation between the morphologic nuclear features and clinicopathologic parameters in cases of colorectal adenocarcinoma.

METHODS

Morphometric nuclear features (nuclear area, perimeter, and shape) were analyzed in 343 patients with colorectal carcinoma and in 57 patients with colorectal adenoma. In each case, 300 nuclei of carcinoma or adenoma cells were analyzed on routine hematoxylin and eosin stained slides by means of a computer-assisted image analysis system that involved tracing the nuclear profiles (magnification x400) on a computer monitor. The morphometric data were compared with patients' survival, clinicopathologic status, and DNA ploidy pattern of tumors.

RESULTS

The mean nuclear area (NA) enlarged from normal colorectal mucosa to adenoma and carcinoma (normal mucosa: n = 343, mean NA = 19 micrometer(2); adenoma: n = 57, mean NA = 34 micrometer(2); mucosal carcinoma: n = 15, mean NA = 45 micrometer(2); P < 0.001). In 343 colorectal carcinomas, NAs of cancer cells in tumors with lymphatic invasion, venous invasion, lymph node metastasis, or hepatic metastasis were significantly larger than those of cancer cells in tumors without such factors. The mean NA of DNA aneuploid tumors was larger than that of DNA diploid tumors (P < 0.001). The nuclear area of cancer cells was determined to be one of the independent prognostic factors in multivariate analysis (P < 0.001). Moreover, the large nuclear area of cancer cells was recognized as one of the risk factors of metachronous hematogenic metastasis in patients after curative surgery.

CONCLUSIONS

Data from computerized morphometry are objective and can be obtained rapidly by conventional microscopic analysis. The nuclear area of cancer cells appears to predict 1) the ability of cancer cells to invade the microvessels in the colorectal wall and 2) the ability of cancer cells to metastasize to the lymph nodes or liver. Therefore, nuclear morphometry is beneficial in mass screening to select patients who are at risk of hematogenic or lymph node metastatic recurrence after curative surgery for colorectal carcinoma.