gms | German Medical Science

Lmyph node staging is the most important prognostic factor after redical surgery in colorectal carcinoma. The chance to correctly classify a colorectal tumor increases with the number of lymph nodes obtained. The latter varies with the method of sampling used by the pathologist. Thus an accurate examination of the surgical specimens is vitally important in order to achieve correct assessment of the lymph node status of a tumor. The purpose of this study was to evaluate an easy method of fat clearing by use of pure aceton. 188 surgical specimens of colorectal carcinoma wer investigated. The first lymph node preparation was carried out manueally. Afterwards the mesenterial adipose tissue was put into pur acetone for 16 hours and then submitted to a second examination for lymph nodes. In 111 out of 188 samples the minimum number of 12 lymph nodes regquired according of the TNM classification was not reached by the manual method of preparation. After acetone treatment twelve or mor of them were yielded in 91% of these samples (average 27 lymph nodes). 29 samples (=15%) exhibited additional lymph node metastases, an din 16 samples (=8% of all samples) an upstage of the N-stage became necessary. This illustrates the importance of our method for optimizing lmyph node staging in cases of colorectal neoplasms. The preparation of lymph nodes following acetone treatment is an easily applicable and low cost method resulting in a much higher number of lymph nodes obtained for a more accurate staging in patients with colorectal cancer.