RESUMEN
INTRODUCTION: Ductal carcinoma in situ (DCIS) is the disease with increasing incidence. Nowadays, approximately 80% DCIS are diagnosed via mammography and represent more than 20% of all types of breast cancer. The acceptance of surgical procedures with this type of breast carcinoma is controversial as primary diagnosis of non-invasive carcinoma is often underestimated and in the end, histopathological examination reveals invasive carcinoma with biological potential to metastasize. In cases of "risk" patient groups with DCIS, several studies report lymph node metastases. The aim of the study has been to assess the incidence of sentinel lymph node metastatic involvement in high-risk patient group with DCIS and in ductal carcinoma in situ with microinvasion (DCISMI), to note the incidence of invasive carcinoma in definitive histopathology in patients with pre-operative diagnosis of DCIS and to analyze some predictors of invasivity. STUDY TYPE AND PATIENT GROUP: In retrospective analysis, we evaluated the setting of 119 patients who have been operated on at our Clinic from January, 1st 2008 until December, 31th 2010 for the diagnosis of DCIS. Prospectively, we have created the setting of 44 patients with high-risk DCIS with sentinel lymph node biopsy (SLNB) performed. METHODS AND RESULTS. Metastatic involvement of sentinel lymph node in high-risk DCIS has been found in 4 cases (9.0%)--in 1 patient (2.2%) with correct diagnosis of DCIS and in 3 patients (6.8%) with invasive carcinoma according to final histopathology. In the patient with DCIS, a micrometastasis of 0.4 mm was found in one sentinel lymph node. After complete axillary dissection, non-sentinel axillary lymph nodes metastatic involvement was not demonstrated (14/0). In 6 cases (5.0%), we identified DCISMI and did not find metastasis in sentinel lymph node. In the high-risk DCIS group, in 4 patients (9.0%) DCISMI and in 12 patients (27.2%) invasive carcinoma was found after definitive histopathologic examination. In this group, the overall ratio of invasive lesions was 36.2%. As for predictors of invasivity, high-grade carcinoma (OR 4.2; 95% CI 1,40-12,58) has more than 4-fold higher influence and lesion size