Asymmetries in pelvic lymph nodes and their metastatic involvement by gynecologic cancer cells

AIM: The aims of this study were to re-examine left-right asymmetry in pelvic lymph node distribution in patients with gynecologic malignancies, and to investigate if there is a left-right asymmetry in pelvic lymph node metastatic involvement by gynecologic cancer cells. METHODS: The oncologic database of our gynecologic department was reviewed to identify patients who had pelvic lymphadenectomy as part of treatment for a variety of gynecologic malignancies. Right and left lymph node counts with and without involvement of cancer cells were retrieved from the pathological reports. RESULTS: Three hundred and thirteen patients were included in the study. The numbers of external iliac, and hypogastric + obturator lymph nodes were higher on the right side than on the left in all gynecologic malignancies. The numbers of involved external iliac, and hypogastric + obturator lymph nodes by metastatic cancer cells were significantly higher on the right side than on the left in all gynecologic malignancies. CONCLUSION: The results suggest the existence of a left-right asymmetry in pelvic lymph node distribution and pelvic lymph node distribution involved by gynecologic cancer cells. This situation may be due to the asymmetry in the number of pelvic lymph nodes. In addition, stronger cell-mediated immune activity in the left side of humans may be associated with the blocking of metastatic invasion of cancer cells from gynecologic malignancies in the left side of the body.