Tumor angiogenesis in lymph node-negative rectal cancer: Correlation with clinicopathological parameters and prognosis

Abstract

Background: Intratumoral microvessel density (MVD) could be used as a prognostic factor in colorectal cancer. We retrospectively analyzed the value of microvessel count in predicting the clinical outcome of stage I and II (Dukes A and B) rectal cancer patients.Methods: Eighty-four patients who had undergone curative resection of lymph node-negative rectal cancer were included. Tumor type and differentiation, the depth of local invasion, venous invasion, the character of the invasive margin, and the degree of lymphocytic infiltration were evaluated for each tumor specimen. Immunohistochemical staining for the CD31 endothelial antigen was performed to highlight the microvessels.Results: The median value of MVD was 45 microvessels. Low MVD (microvessels Յ45) was observed in 41 patients (48.8%), and high MVD (Ͼ45) was found in 43 (51.2%). The presence of conspicuous lymphocytic infiltration was significantly associated with increased vessel density. With uni-and multivariate survival analysis MVD did not show any prognostic significance. The character of the invasive margin was the only parameter with independent prognostic value.Conclusions: MVD does not seem to provide any additional prognostic information when compared with standard histopathological parameters in lymph node-negative rectal cancer. It is likely that the strong association between MVD and the presence of conspicuous lymphocytic infiltration may interfere with its predictive value.

Fatores de mau prognóstico nas peças operatórias de pacientes submetidos ao tratamento cirúrgico do câncer colorretal

“…A profundidade da invasão local, ou seja, o grau de penetração tumoral através da parede intestinal têm sido identificado como um fator prognóstico 13,14,18 independente de sobrevida 13,18 , e associa-se a um maior risco de recidiva tumoral 5 . Segundo a classificação TNM e de Dukes, a sobrevida é de 91 a 99% para tumores que não comprometem além da muscular pró-pria, de 77 a 87% para aqueles além desta, e de 53 a 73% para os com metástase ganglionar 5 .…”

The influence of invasive growth pattern and microvessel density on prognosis in colorectal cancer and colorectal liver metastases

“…Angiogenesis is a fundamental requirement for tumour growth, invasion, and metastasis formation (Folkman, 1986). The assessment of microvessel density (MVD) is frequently used to quantify angiogenesis in archival tissue (Hlatky et al, 2002), although its use as a prognostic indictor is controversial.…”

“…In breast cancer (Uzzan et al, 2004), non-small cell lung carcinoma (Ushijima et al, 2001) and melanoma (Ribatti et al, 2003), a high MVD is associated with poor outcome. In CRC, a high MVD has been shown to predict disease recurrence and survival in some studies (Saclarides et al, 1994;Tanigawa et al, 1997), whereas other studies have shown an association between high MVD and improved survival (Prall et al, 2003) or have concluded that MVD failed to provide additional prognostic information (Cianchi et al, 2002).…”

Assessment of angiogenesis expression and its relationship with prognosis of colorectal cancer by conventional and computer-assisted histopathological image analysis

“…Its objective was thus to determine the degree of angiogenesis in colorectal tumors, by measuring the endothelial area via a computerized method, and to study its relationship with MVD. Our first observation, as found by other authors 21,24,25 , was that computerized readings of endothelial areas were feasible and that this would enable precise estimation of the degree of neovascularization of the tumoral tissue. However, our results demonstrated that there is a low correlation between microvessel density and the area occupied by vascular endothelium.…”

“…It has already been demonstrated that neovascularization is associated with tumor growth and that the possibility exists that tumors with greater numbers of microvessels are related to metastases 16,17,18 . In fact, a relationship between the degree of microvessel density and worse prognosis for colorectal cancer has been observed in several studies 4,5,19 , although this has not been confirmed by some other authors 20,21,22 . These differences in results have been attributed in part to limitations in the traditional method for assessing angiogenesis 7,8,23 .…”