Incidence and survival of patients with Dukes' A (stages T1 and T2) colorectal carcinoma: a 15-year population-based study

The "Classification Pendulum" of Stage I Colorectal Cancer: A National Level Analysis of the Survival Difference Between T1 and T2 Colorectal Cancer

BACKGROUND

The eighth edition of the American Joint Committee on Cancer classifies nonmetastatic, node-negative colorectal cancers invading the submucosa (T1) and muscularis propria (T2) as stage I tumors without additional subclassification.

OBJECTIVE

The aim of the study was to compare survival of T1N0M0 versus T2N0M0 colorectal cancers and to investigate factors associated with decreased survival.

DESIGN

This was an analysis of 2 large population-based data sets.

SETTINGS

The study was conducted analyzing data from the Surveillance Epidemiology and End Result program and the National Cancer Database.

PATIENTS

Adult patients undergoing major resection without additional therapy for stage I colorectal cancer were included.

MAIN OUTCOME MEASURES

Overall and disease-specific survival for T1 versus T2 cancers were measured. Subgroup analyses by tumor location (colon versus rectum) were performed.

RESULTS

A total of 30,228 (36.4% T1 and 63.6% T2) and 41,670 (41.1% T1 and 58.9% T2) patients were identified in the Surveillance Epidemiology and End Result database and the National Cancer Database. The 5-year overall survival rates were 87.1% and 86.2% for patients with T1 versus 82.7% and 80.7% for patients with T2 (p < 0.001) in the Surveillance Epidemiology and End Result database and the National Cancer Database. The 10-year overall survival rates were 71.3% and 66.3% for patients with T1 versus 62.2% and 57.2% for patients with T2 tumors (p < 0.001) in the Surveillance Epidemiology and End Result database and the National Cancer Database. The 5- and 10-year disease-specific survival for colorectal cancer in the Surveillance Epidemiology and End Result database was 97.0% (T1) versus 95.2% (T2) and 94.1% (T1) versus 90.3% (T2). Black race (HR = 1.26 and 1.65 for overall survival and disease-specific survival in the Surveillance Epidemiology and End Result database; HR = 1.20 for overall survival in the National Cancer Database) was associated with worse survival.

LIMITATIONS

The study was limited by intrinsic biases related to large administrative data sets.

CONCLUSIONS

Within stage I colorectal cancer, T2 tumors have decreased overall survival and disease-specific survival as compared with T1 cancers. This survival difference may justify revising the American Joint Committee on Cancer staging system to include the subclassification of stage Ia (T1N0M0) and stage Ib (T2N0M0). See Video Abstract at http://links.lww.com/DCR/B659.

LA CLASIFICACIN PNDULO PARA EL CNCER COLORRECTAL EN ESTADIO I UN ANLISIS A NIVEL NACIONAL DE LA DIFERENCIA DE SOBREVIDA ENTRE EL CNCER COLORRECTAL T Y T

ANTECEDENTES:La octava edición del American Joint Committee on Cancer, clasifica los cánceres colorrectales no metastásicos con ganglios negativos, que invaden la submucosa (T1) y la muscularis propia (T2) como tumores en estadio I sin subclasificación adicional.OBJETIVO:El objetivo del estudio fue comparar la sobrevida de los cánceres colorrectales T1N0M0 versus T2N0M0 e investigar los factores asociados con la disminución de la sobrevida.DISEÑO:Análisis de dos grandes conjuntos de datos poblacionales.MARCO:El estudio se realizó analizando datos del Programa de Epidemiología de Vigilancia y Resultados Finales (SEER) y la Base de Datos Nacional del Cáncer.PACIENTES:Pacientes adultos en los cuales se realizó una resección mayor sin terapia adicional por cáncer colorrectal en estadio I.PRINCIPALES VARIABLES ANALIZADAS:Sobrevida global y específica de la enfermedad para los cánceres T1 versus T2. Se realizó un análisis de subgrupos según la ubicación del tumor (colon versus recto).RESULTADOS:Se incluyeron un total de 30.228 (36,4% T1 y 63,6% T2) y 41.670 (41,1% T1 y 58,9% T2) pacientes en las bases de datos SEER y la Base de Datos Nacional del Cáncer, respectivamente. La sobrevida global a 5 años fue del 87,1% y el 86,2% para los pacientes con T1 frente al 82,7% y el 80,7% de los pacientes con T2 (p < 0,001) en el SEER y la Base de Datos Nacional del Cáncer, respectivamente. La sobrevida global a 10 años fue del 71,3% y el 66,3% para los pacientes con T1 frente al 62,2% y el 57,2% de los pacientes con tumores T2 (p < 0,001) en el SEER y la Base de Datos Nacional del Cáncer, respectivamente. La sobrevida específica de la enfermedad a 5 y 10 años para el cáncer colorrectal en el SEER fue del 97,0% (T1) frente al 95,2% (T2) y del 94,1% (T1) frente al 90,3% (T2), respectivamente. La grupo étnico afroamericano se asoció con una sobrevida menor (Hazard Ratio -HR 1,26 y 1,65 para la sobrevida general y sobrevida específica de la enfermedad-SEER; HR 1,20 para la sobrevida general-Base de de Datos Nacional del Cáncer).LIMITACIONES:Sesgos intrínsecos relacionados con el análisis de grandes conjuntos de datos.CONCLUSIONES:Dentro del cáncer colorrectal en estadio I, los tumores T2 han disminuido la sobrevida general y la sobrevida específica de la enfermedad, en comparación con los cánceres T1. Esta diferencia de sobrevida puede justificar la revisión del sistema de estadificación del American Joint Committee on Cancer para incluir la subclasificación del estadio Ia (T1N0M0) y el estadio Ib (T2N0M0). Consulte Video Resumen en http://links.lww.com/DCR/B659.

Emergency surgery for complicated colorectal cancer in central Brazil

Objective to report clinical and pathological features of patients with colorectal cancer diagnosed during emergency abdominal surgery.

Methods records of 107 patients operated between 2006 and 2010 were reviewed.

Results there were 58 women and 49 men with mean age of 59.8 years. The most frequent symptoms were: abdominal pain (97.2%), no bowel movements (81.3%), vomiting (76.6%), and anorexia (40.2%). Patients were divided into five groups: obstructive acute abdomen (n = 68), obstructive acute perforation (n = 21), obstructive acute inflammation (n = 13), abdominal sepsis (n = 3), and severe gastrointestinal bleeding (n = 2). Tumors were located in the rectosigmoid (51.4%), transverse colon (19.6%), ascendent colon (12.1%), descendent colon (11.2%), and 5.6% of the cases presented association of two colon tumors (synchronic tumors). The surgical treatment was: tumor resection with colostomy (85%), tumor resection with primary anastomosis (10.3%), and colostomy without tumor resection (4.7%). Immediate mortality occurred in 33.4% of the patients. Bivariate analysis of sex, tumor location and stage showed no relation to death (p > 0.05%).

Conclusions colorectal cancer may be the cause of colon obstruction or perfuration in patients with nonspecific colonic complaints. Despite the high mortality rate, resection of tumor is feasible in most patients.

Number of Lymph Nodes in Primary Nodal Basin and a “Second Look” Protocol as Quality Indicators for Optimal Nodal Staging of Colon Cancer

Context.—Evaluation of 12 or more lymph nodes (LNs) is currently used as a quality indicator for adequacy of pathologic examination of colon cancer resections.

Objective.—To evaluate the utility of a focused LN search in the immediate vicinity of the tumor and a “second look” protocol in improving LN staging in colon cancer.

Design.—Lymph nodes were submitted separately from the primary nodal basin (PNB) and secondary nodal basin (SNB) defined as an area less than 5 cm away and an area greater than 5 cm away from the tumor edge, respectively, in 201 consecutive resections (2010–2013). One hundred sixty-eight consecutive tumors (2006–2009) were used as a control group. A second search was performed in all cases that were N0 after the first search.

Results.—In cases that were N0 after the first search, 20.9 ± 10.8 LNs were collected from the PNB, compared to 8.5 ± 9.1 from the SNB. Positive LNs were found in N+ tumors in the PNB in all cases but in only 9% (4 of 46) of SNBs (P &lt; .001). A second search increased node count by an average of 10 additional LNs. In 5 of 114 cases (4.4%), N0 after the first search converted to N+ after a second search that yielded 1 to 4 positive LNs, all of which were in the PNB.

Conclusions.—Emphasis on the number of LNs examined from the PNB and a “second look” protocol improve nodal staging.

Cost-effectiveness of aspirin adjuvant therapy in early stage colorectal cancer in older patients

BACKGROUND & AIMS

Recent observational studies showed that post-operative aspirin use reduces cancer relapse and death in the earliest stages of colorectal cancer. We sought to evaluate the cost-effectiveness of aspirin as an adjuvant therapy in Stage I and II colorectal cancer patients aged 65 years and older.

METHODS

Two five-state Markov models were constructed separately for Stage I and II colorectal cancer using TreeAge Pro 2014. Two hypothetical cohorts of 10,000 individuals at a starting age of 65 years and with colorectal cancer in remission were put through the models separately. Cost-effectiveness of aspirin was evaluated against no treatment (Stage I and II) and capecitabine (Stage II) over a 20-year period from the United States societal perspective. Extensive one-way sensitivity analyses and multivariable Probabilistic Sensitivity Analyses (PSA) were performed.

RESULTS

In the base case analyses, aspirin was cheaper and more effective compared to other comparators in both stages. Sensitivity analyses showed that no treatment and capecitabine (Stage II only) can be cost-effective alternatives if the utility of taking aspirin is below 0.909, aspirin's annual fatal adverse event probability exceeds 0.57%, aspirin's relative risk of disease progression is 0.997 or more, or when capecitabine's relative risk of disease progression is less than 0.228. Probabilistic Sensitivity Analyses (PSA) further showed that aspirin could be cost-effective 50% to 80% of the time when the willingness-to-pay threshold was varied from USD 20,000 to USD 100,000.

CONCLUSION

Even with a modest treatment benefit, aspirin is likely to be cost-effective in Stage I and II colorectal cancer, thus suggesting a potential unique role in secondary prevention in this group of patients.

Sleep fragmentation in mice induces nicotinamide adenine dinucleotide phosphate oxidase 2-dependent mobilization, proliferation, and differentiation of adipocyte progenitors in visceral white adipose tissue

BACKGROUND

Chronic sleep fragmentation (SF) without sleep curtailment induces increased adiposity. However, it remains unclear whether mobilization, proliferation, and differentiation of adipocyte progenitors (APs) occurs in visceral white adipose tissue (VWAT), and whether nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2) activity plays a role.

METHODS

Changes in VWAT depot cell size and AP proliferation were assessed in wild-type and Nox2 null male mice exposed to SF and control sleep (SC). To assess mobilization, proliferation, and differentiation of bone marrow mesenchymal stem cells (BM-MSC), Sca-1+ bone marrow progenitors were isolated from GFP+ or RFP+ mice, and injected intravenously to adult male mice (C57BL/6) previously exposed to SF or SC.

RESULTS

In comparison with SC, SF was associated with increased weight accrual at 3 w and thereafter, larger subcutaneous and visceral fat depots, and overall adipocyte size at 8 w. Increased global AP numbers in VWAT along with enhanced AP BrDU labeling in vitro and in vivo emerged in SF. Systemic injections of GFP+ BM-MSC resulted in increased AP in VWAT, as well as in enhanced differentiation into adipocytes in SF-exposed mice. No differences occurred between SF and SC in Nox2 null mice for any of these measurements.

CONCLUSIONS

Chronic sleep fragmentation (SF) induces obesity in mice and increased proliferation and differentiation of adipocyte progenitors (AP) in visceral white adipose tissue (VWAT) that are mediated by increased Nox2 activity. In addition, enhanced migration of bone marrow mesenchymal stem cells from the systemic circulation into VWAT, along with AP differentiation, proliferation, and adipocyte formation occur in SF-exposed wild-type but not in oxidase 2 (Nox2) null mice. Thus, Nox2 may provide a therapeutic target to prevent obesity in the context of sleep disorders.

Clinical outcome of low- and high-risk malignant colorectal polyps: results of a population-based study and meta-analysis of the available literature

Some histological features of malignant polyps have been used to classify patients into low- and high-risk groups. This study proposed to evaluate the impact of this classification on the clinical outcome of patients with malignant polyps. Through the Colorectal Cancer Registry, 105 patients with endoscopically removed malignant polyps were selected. The presence of one of the following histological features defined malignant polyps as high-risk: infiltrated resection-margin, poorly differentiated carcinoma, lymphatic/vascular invasion and tumour budding and depth of submucosal invasion. Available literature was reviewed by applying a similar classification. Most of the malignant polyps were pedunculated and were localized in the left colon. Fifty-five malignant polyps were classified as low-risk lesions and 50 as high-risk. None of the patients at low-risk died of colorectal cancer. Of the patients at high-risk, three died of cancer; all three cases showed lymphatic/vascular invasion. Review of the literature reveals that an unfavourable clinical outcome is significantly more prevalent in the high-risk compared with the low-risk group (p > 0.005). Moreover, all histological risk factors show a specific predictive value of clinical adverse outcome. Our study and the pooled data analysis confirmed the usefulness of the subdivision into low- and high-risk malignant polyps for management of patients with endoscopically removed colorectal carcinoma.

Incidence trend of malignant polyps through the data of a specialized colorectal cancer registry: clinical features and effect of screening

OBJECTIVES

The purposes of the study are to describe the incidence trend of malignant polyp of large bowel over a 25-year period in the District of Modena and to assess the effect of an organized colorectal cancer screening program.

MATERIAL AND METHODS

Through the data of a specialized colorectal cancer Registry, we evaluate the clinical and pathological features of the polyps. Trend analysis was assessed with the Joinpoint Regression Program.

RESULTS

A total of 172 patients with malignant polyps were diagnosed throughout the study (3.5% of 4.835 registered patients); their overall frequency during the registration period increased from zero cases in the initial years (1984-85) to 57 cases in the past 3 years (2006-2008). Crude incidence rate passed from 0.37 in 1986-89 to 10.2 in 2006. Joinpoint trend analysis of crude rates showed a significant increase of incidence during the study period, with percent of annual variation ranging between 38.6% (95% CI 12.5-70.7) and 7.3% (95% CI 2.6-12.1). During the screening period (2005-2008, the past 4 years of registration) there was a significant increase of sessile polyps (p < 0.001), while other clinical and morphological features, including the number of low- and high-risk malignant polyps, remained unchanged. The surgery (after polypectomy) tended to raise both in low- and high-risk subgroups.

CONCLUSION

The incidence of malignant polyps increased significantly from the initial to the most recent periods of colorectal cancer registration. Screening was associated with changes in gross morphology of polyps and with an increased use of the surgery after endoscopic polypectomy.

Cost of care for colorectal cancer in Ireland: a health care payer perspective

OBJECTIVE

Management options for colorectal cancer have expanded in recent years. We estimated average lifetime cost of care for colorectal cancer in Ireland in 2008, from the health care payer perspective.

METHOD

A decision tree model was developed in Microsoft EXCEL. Site and stage-specific treatment pathways were constructed from guidelines and validated by expert clinical opinion. Health care resource use associated with diagnosis, treatment and follow-up were obtained from the National Cancer Registry Ireland (n=1,498 cancers diagnosed during 2004-2005) and three local hospital databases (n=155, 142 and 46 cases diagnosed in 2007). Unit costs for hospitalisation, procedures, laboratory tests and radiotherapy were derived from DRG costs, hospital finance departments, clinical opinion and literature review. Chemotherapy costs were estimated from local hospital protocols, pharmacy departments and clinical opinion. Uncertainty was explored using one-way and probabilistic sensitivity analysis.

RESULTS

In 2008, the average (stage weighted) lifetime cost of managing a case of colorectal cancer was €39,607. Average costs were 16% higher for rectal (€43,502) than colon cancer (€37,417). Stage I disease was the least costly (€23,688) and stage III most costly (€48,835). Diagnostic work-up and follow-up investigations accounted for 4 and 5% of total costs, respectively. Cost estimates were most sensitive to recurrence rates and prescribing of biological agents.

CONCLUSION

This study demonstrates the value of using existing data from national and local databases in contributing to estimating the cost of managing cancer. The findings illustrate the impact of biological agents on costs of cancer care and the potential of strategies promoting earlier diagnosis to reduce health care resource utilisation and care costs.

Neutrophil gelatinase-associated lipocalin: a new prognostic marker in stage I colorectal carcinoma?

TNM stage I colorectal cancer is commonly characterized by a good prognosis, with 5-year survival of around 80% to 90%. Nonetheless, disease progression occurs in a percentage of cases, although the causes of an adverse clinical course still remain to be clarified. In the present study, we analyzed and compared the immunohistochemical expression of neutrophil gelatinase-associated lipocalin, an iron-binding protein, which is involved in colorectal cancer progression, in series a of 29 surgically resected colorectal carcinomas obtained from patients who died of the disease and in a cohort of 22 colorectal cancers from patients alive 5 years after the initial diagnosis. The prognostic value of neutrophil gelatinase-associated lipocalin expression on the overall survival to colorectal cancer was investigated. Variable neutrophil gelatinase-associated lipocalin immunoexpression was demonstrated in 23 of the 51 analyzed cases, with a significantly higher frequency of positive cases among patients who died of the disease. Moreover, neutrophil gelatinase-associated lipocalin expression appeared to be a significant independent negative prognostic marker related to shorter overall survival in stage I colorectal carcinoma. If our findings are confirmed in further analyses, neutrophil gelatinase-associated lipocalin assessment might be used to select patients with a higher risk of progression and to find adjuvant therapies for the prevention of adverse outcomes.

Neutrophil gelatinase-associated lipocalin immunoexpression in colorectal carcinoma: A stage-specific prognostic factor?

TNM post-surgical staging is considered to be one of the most powerful prognosticators for colorectal carcinoma. Although patient survival mostly decreases concomitantly to stage increase, in a percentage of cases TNM stage appears only to express the anatomic extent of the neoplasia with no correlation with clinical outcome. Thus, the identification of additional prognostic markers for colorectal cancer is required. Neutrophil gelatinase-associated lipocalin (NGAL) is a 25-kDa protein that appears to play an important role in colorectal cancer progression. In order to evaluate whether NGAL expression may be considered as a predictor of colorectal cancer progression, we analyzed its correlation with clinicopathological characteristics, as well as with patient progression-free survival in a series of surgically resected colorectal carcinomas. A variable NGAL immunoexpression was found in 24 out of the 64 analyzed cases. When only the positive cases were considered, a significant association was found between a high NGAL expression and the presence of distant metastases or high tumor stage. In addition, the presence of NGAL was a significant negative prognostic marker correlated with a shorter progression-free survival in stage I colorectal carcinoma, but not in the remaining TNM stages. If our findings are confirmed in more extensive analyses on stage I colorectal carcinoma, NGAL assessment may be used in order to select those patients with a higher progression risk and to submit them to adjuvant therapies useful to prevent adverse outcome.

Stage I colorectal carcinoma: VEGF immunohistochemical expression, microvessel density, and their correlation with clinical outcome

Tumor-node-metastasis (TNM) stage I colorectal cancer is commonly characterized by a good prognosis, with 5-year survival around 80-90%; nonetheless, it undergoes disease progression in a percentage of cases, although the causes of adverse clinical course still remain to be elucidated. In the present study, we analyzed and compared the immunohistochemical expression of the pro-angiogenic vascular endothelial growth factor (VEGF) as well as the microvessel density (MVD) in a series of 27 surgically resected colorectal carcinomas obtained from patients deceased because of disease progression and in a cohort of 25 colorectal cancers from patients still alive with no evidence of disease progression 5 years after the initial diagnosis. The prognostic value of VEGF expression and of MVD on the overall survival to colorectal cancer was investigated. A variable VEGF immunoexpression was demonstrated in all the analyzed cases. High VEGF expression was significantly more frequent among patients deceased of the disease. These patients also displayed significantly higher MVD counts in their cancer in comparison to the patients alive after 5 years from surgery. Moreover, both high VEGF expression and MVD appeared as significant negative prognostic markers related to a shorter overall survival to stage I colorectal carcinoma, with VEGF representing an independent variable at multivariate analysis. VEGF assessment might be used in order to select those patients with a higher progression risk and to submit them to adjuvant therapies useful to prevent adverse outcome.

Serum cellular apoptosis susceptibility protein is a potential prognostic marker for metastatic colorectal cancer

Colorectal cancer has high rates of recurrence and metastasis. Many patients with similar histopathological features show significantly different clinical outcomes, and these differences are primarily related to metastases undetected by current diagnostic methods. There is no useful serological marker for metastatic disease. We investigated the cellular apoptosis susceptibility (CSE1L/CAS) protein in comparison with carcinoembryonic antigen (CEA) as a marker for metastatic colorectal cancer. Using serum from 103 patients with stage I, II, III, and IV disease, CSE1L was detected in 36.0% (9 of 25), 57.7% (15 of 26), 71.4% (30 of 42), and 88.9% (8 of 9) of patients, respectively; a pathological CEA level was found in 16.0% (4 of 25), 42.3% (11 of 26), 47.6% (20 of 42), and 77.8% (7 of 9) of patients, respectively; a combined CSE1L/CEA assay was detected in 48.0% (12 of 25), 65.4% (17 of 26), 88.1% (37 of 42), and 100% (9 of 9) of patients, respectively. Lymphatic metastasis is an important predictor of poor prognosis and crucial for determination of therapeutic strategy. Serum CSE1L was detected in 74.5% (38 of 51) of patients with lymph node metastasis, whereas a pathological CEA level was found in only 52.9% (27 of 51) of the same patients (P < 0.001); the combined CSE1L/CEA assay increased sensitivity to 90.2% (46 of 51). Animal experiments showed CSE1L reduction in B16-F10 melanoma cells correlated with decreased metastasis to the colorectal tract in C57BL/6 mice. These results indicate that assay of serum CSE1L may facilitate diagnosis of colorectal cancer lymphatic metastases; furthermore, CSE1L is a possible therapeutic target.

Prognostic value of microvascular density in dukes a and B (t1-t4, n0, m0) colorectal carcinomas

Background. Aproximatelly 30% of patients operated on for colorectal cancer (CRC), with an expectedly favourable prognosis (Dukes A-B/T1–T4, N0, M0) suffer recurrence and/or die. Method. In order to determine if tumor microvascular density (MVD) is a prognostic factor in CRC, samples from tumors of 104 Dukes A-B CRC patients were retrospectively studied. Immunohistochemistry was performed for anti-CD34 antibody to visualize tumor vascularisation. MVD was expressed as the total number of vessels and as the percentage of microvascular area. We calculated MVD with a morphometry program and performed descriptive, bivariate, and survival statistics. Results. The mean number of vessels was 37.37/200x field, and the mean vascular area was the 3.972%. 30% of the patients with < 37 vessels/field, and 21% of the patients with > 37 vessels/field, experienced recurrence/death. The 35% of patients with < 4% of vascular area died following recurrence, compared with 14% of patients with ≥4% of vascular area. These differences in % of vascular area were statistically significant. Conclusion. MVD expressed as the total number of vessels had no a statistically significant influence on the evolution of CRC. However, neoplasias with a greater % of vascular were associated to a better outcome.

Management dilemma; a woman with cystic fibrosis and severe lung disease presenting with colonic carcinoma: a case report

Introduction

There are increasing reports of bowel cancer in cystic fibrosis, suggesting a possible causal link. Individuals with cystic fibrosis who have advanced lung disease present a high operative risk, limiting curative treatment options in early bowel malignancy.

Case presentation

We describe a 41-year-old Caucasian woman with cystic fibrosis and severe lung disease who had been considered for lung transplantation, who presented with rectal bleeding and was found to have a Stage I adenocarcinoma of the sigmoid colon. After considerable discussion as to the operative risks, she underwent a laparoscopic resection and remains relatively well 1 year postoperatively with no recurrence.

Conclusion

We discuss the complexity of the management decisions for cystic fibrosis patients with severe lung disease and early stage colonic malignancy, particularly in the context of potential need for lung transplantation. The case demonstrates that cystic fibrosis patients with very severe lung function impairment may undergo laparoscopic abdominal surgical interventions without compromising postoperative airway clearance.

Prognostic significance of histological features and biological parameters in stage I (pT1 and pT2) colorectal adenocarcinoma

Patients with stage I colorectal cancer have a good prognosis, however, a small fraction of them die of local or distant recurrence after curative resection. The aggressive behavior reflects some biological properties of these tumors. In this study, we evaluated the prognostic role of some histopathological and biological parameters in stage I colorectal carcinomas. From the Colorectal Cancer Registry of Modena, we selected two series of patients; the first included all patients who had died of disease progression, the second included patients with a favorable outcome. The histopathological parameters assessed were grade of differentiation, growth pattern at the invasive tumor front, peritumoral lymphocytic infiltration, tumor budding and vascular invasion. The biological variables were proliferative activity (using Ki-67 nuclear antigen), overexpression of p53 protein and altered expression of the mismatch repair proteins (MLH1 and MSH2). The results showed that an infiltrating growth pattern, absent or sparse peritumoral lymphocytic infiltration, the presence of tumor budding and vascular invasion are significantly related to the risk of recurrence. Among the biological parameters, p53 overexpression was significantly correlated with a poor clinical outcome. Our study showed that the histopathologial features are relevant prognostic indicators and might be used as markers for an appropriate treatment strategy in patients with stage I carcinomas.

The science and politics of colorectal cancer screening

Hoff and Bretthauer discuss the scientific and political controversies surrounding the introduction of a national screening programme for colorectal cancer.