The role of tumoral stroma in determining the forecast of recurrence and fatal consequence of stage IIA-IIIB colorectal cancer

Colorectal cancer (CRC) ranks 2nd in the structure of mortality from malignant neoplasms (MN). One of the criteria for the prognosis of CRC may be a tumor stroma, which has not been widely used in clinical practice. The aim was to determine the main morphological features of the stroma CRC T3N0-2M0 and search for prognostic criteria for their recurrence and lethal outcome according to the operating material and autopsy. Materials and methods. Group I included primary CRC without recurrence. The average recurrence-free period was 5 years (62.5±16.5 months). Group II – primary CRC with recurrence; IIA – with recurrences within 5 years from the date of tumor removal that did not lead to death; IIB – with the appearance of recurrence and lethal consequence of the generalization of the tumor process within 5 years from the moment of removal of the primary tumor. CRC micropreparations made according to the standard method with G + E staining were studied; immunohistochemical study was performed using monoclonal antibodies to smooth muscle actin alpha. Results. Stromal-parenchymal ratio >50 % is a prognostic criterion for recurrence (p<0.05) and shorter recurrence-free survival (p<0.001) of patients with stage IIA-IIIB CRC. Immature stroma type CRC stage IIA-IIIB is associated with the presence of tumor budding (p<0.001), G3 differentiation (p<0.01), shorter recurrence-free survival (p<0.001); among recurrent CRCs, the immature type of stroma is associated with the lethal outcome of patients (p<0.05). Expressed levels of tumor-activated fibroblasts are one of the criteria for immature CRC stroma (p<0.003), but as an independent prognostic criterion has limited prognostic value. Conclusions. TSR and immature type of stroma are prognostic criteria for recurrence and recurrence period of CRC pT3N0-2M0, more typical of tumors of patients with recurrence and lethal outcome with the same ratio of tumors by differentiation.