title: The spread pattern of right and left epithelial ovarian cancers.
abstract: OBJECTIVE
  No attention has been paid in the past to the spread pattern of right and left epithelial carcinomas of the ovaries. We aimed to investigate the incidence, spread pattern and distribution of lymph node metastasis in epithelial ovarian cancer (EOC), comparing right versus left EOC of any stage, where the contralateral ovary is apparently and histologically tumor-free.
  
  
  METHODS
  Out of a total of 442 patients with EOC, 318 (72%) patients in the study had bilateral and 124 (28%) patients had unilateral ovarian cancer. The study enrolled 60 (48%) patients with right and 64 patients with left ovarian involvement (52%) where the contralateral ovary was tumor-free. Groups Right and Left were compared in terms of age, the tumor status of the lymph nodes, surgical stage, histology, grade, tumor extension out of the ovaries, omental tumor involvement and also omental and nodal involvement together.
  
  
  RESULTS
  The comparisons of the variables between Groups Right and Left did not show significant differences except for metastasis patterns in the left iliac lymph nodes and omentum (p < 0.05). Independent of age and histological type of the tumor, women with left-side EOC showed a significantly higher incidence of metastasis in the left iliac lymph nodes (OR: 7.04, 95% CI, 1.36-36.44) and omentum (OR: 2.87, 95% CI, 1.03-8.01), when compared to right-side EOC (p < 0.05).
  
  
  CONCLUSIONS
  In this cohort of patients, we found that left-side unilateral EOC was more likely to metastasize to the left iliac lymph nodes and omentum than the right side where the contralateral ovary was tumor-free. This might be due to the difference in lymphatic drainage on the right and left side and/or the influence of peritoneal fluid movements. This suggestion needs to be supported by further studies.
authors.affiliation: Department of Obstetrics and Gynecology, Başkent University, Faculty of Medicine, Ankara, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Ayhan
authors.forename: H
authors.initials: H
authors.lastname: Yüksel
authors.forename: P
authors.initials: P
authors.lastname: Dursun
mesh_terms: D000328:Adult; D000368:Aged; D000077216:Carcinoma, Ovarian Epithelial; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D015994:Incidence; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology*; D009367:Neoplasm Staging; D009375:Neoplasms, Glandular and Epithelial / Q000453:epidemiology / Q000473:pathology; D016017:Odds Ratio; D010051:Ovarian Neoplasms / Q000453:epidemiology / Q000473:pathology; D011379:Prognosis; D012307:Risk Factors; D014421:Turkey / Q000453:epidemiology; D016387:Women's Health