[Surgical treatment of low anterior resection syndrome]. / Khirurgicheskaya reabilitatsii bol'nykh s sindromom nizkoi perednei rezektsii.

OBJECTIVE: To compare functional outcomes of various rectal reconstruction after total mesorectal excision. MATERIAL AND METHODS: A prospective randomized trial included 90 patients with mid-to-low rectal carcinoma who underwent total mesorectal excision. RESULTS: There were 22 patients after J-pouch surgery, 30 patients with side-to-end anastomoses and 38 patients with end-to-end anastomoses. Eight patients (26.6%) required conversion of J-P to E-E (7 patients) and S-E (1) anastomosis for technical reasons. Postoperative morbidity was similar (13.6, 16.7 and 34.2% in J-P, S-E and E-E groups, respectively, p=0.705). Sensory threshold, earliest and constant defecation urge and maximal tolerable volume were higher for J-P surgery within 3-6-12 months after surgery. Stool frequency was significantly lower after J-P surgery compared to S-E and E-E anastomoses within 3-6-12 months. Wexner scores were 3, 5, 6 after 6 months (p<0.05) and 0, 1, 1 after 12 months for J-P, S-E and E-E, respectively (p>0.05). Evacuation dysfunction was observed in 59.1% with J-P, 33.3% with S-E and 21.1% with E-E anastomoses in 6 months after stoma closure. CONCLUSION: J-pouch reconstruction demonstrates higher neorectal volume that ensures reduced stool frequency up to 12 months after stoma closure. However, technical challenges of J-pouch surgery and evacuation dysfunction restrain application of this procedure in clinical practice.

[Biochip detection of KRAS, BRAF, and PIK3CA somatic mutations in colorectal cancer patients].

Somatic mutations of KRAS, PIK3CA, and BRAF cause insensitivity of colorectal tumors to therapy with anti-EGFR monoclonal antibodies, necessitating a genetic testing prior to therapy. A biological microchip was developed and validated to allow detection of 19 somatic mutations in KRAS, PIK3CA, and BRAF genes. The method combines LNA-clamp PCR and allele-specific hybridization on a microchip and detects mutant DNA in 100 times wild-type background (1%). A total of 66 DNA samples isolated from colorectal tumors were tested with the biochip. Possible associations between the genetic status of the tumor and the patient's characteristics (age, sex, tumor localization, stage, and TMN) were assessed statistically. KRAS mutations were more common in females (P = 0.02) and in patients with distant metastasis (P = 0.04). Other associations between the presence of mutations and patient characteristics were not observed. The method proved highly sensitive and can be used in oncology to select patients who sensitive to therapy with anti-EGFR monoclonal antibodies.