We made use of the computer nonlinear diagnosis method (NLS) to identify early phases of malignant growths in the colon. The obtained data allowed to believe that this method could evaluate the infiltration depth of the tumor within the intenstine wall and allow to diagnose malignant adenopathy which was necessary to make a prognosis and determine tumor resectability.

The average detection rate of tumors in the colon at the NLS-investigation is around 63%. The sensitivity of NLS in diagnosing malignant lymphadenopathy at segmented intestine disease is about 65%. It is higher for rectal tumors because a visualizable lymph node in the adrectal region can be regarded as a malignant one. The detection of lymph nodes during the NLS investigation may be connected to the existence of an inflammatory process. However, perecolonic lymph nodes can be more often diagnosed in patients affected by colonic cancer (71%) than in cases of inflammatory lesions (45%).

The NLS-method can be useful in evaluating the spread of tumor to neighboring organs and tissues as well as metastatic lesions of the liver, adrenals, lungs, etc. The NLS-investigation can be used to:

— determine resectability and need for presurgical radiation therapy;

— plan radiation field;

— detect complications caused by the tumor such as perforation at a formed abscess or pre-obstructive ischemia in patients with fully tumo-occluded intenstine lumen.

The NLS-method allows to distinguish tumor and ischemic changes in the wall in 75% of cases (D<0.425). In most cases the ischemic area is located beside (in closer proximity) the tumorous area, however occasionally an intermediate zone with normal mucous membrane may be detected. The tumor is mostly defined as an unevenly chromogenic area of the intestine wall (from 0.8 to 4.5 cm, 2.0 cm on the average). The ischemic section is largely detected due to a concentric zone of a higher chromogenic pattern (5-6 points according to Flandler's scale), with the zone thickness varying from 0.6 to 1.5 cm (1.0 cm on the average). The timorous area is mostly heterochromatic (4 to 6 points) whereas the ischemic area is generally found to be homochromatic (in 70% of cases).

NLS of metatron 4025 hunter is very important for diagnosing multiple colonic cancers and has considerable advantages over colonoscopy because it allows to detect changes more proximal to the tumor and exactly localize the process in the colon and outside of it. NLS is the only method to diagnose tumor relapses external to the colon.