vascular involvement

Several theories point to direct toxicity or vascular involvement.

Vascular involvement.

The resected specimen is retrieved and submitted for microscopic examination for determination of tumor invasion depth, resection margin, and possible vascular involvement.

Angiography looking for signs like stretched arteries may be used to supplement evaluation of vascular involvement and to determine whether embolization would be helpful if surgery is being considered.

More recent histopathological and microvascular studies suggest that vascular involvement may occur at an earlier stage and play a more important role in the disease process than had previously been supposed.

For patients with hepatic metastasis considered to be resectable (based on a limited number of lesions, intrahepatic locations of lesions, lack of major vascular involvement, absent or limited extrahepatic disease, and sufficient functional hepatic reserve), a negative-margin resection has resulted in 5-year survival rates of 25% to 40% in mostly nonrandomized studies.