title: The clinical significance of lymphangiogenesis in renal cell carcinoma.
abstract: BACKGROUND
  The formation of lymphatic vessels (lymphangiogenesis) occurs in tumor tissues and is crucial for tumor development and progression in some cancers. Lymphangiogenesis and its clinical effect on renal cell carcinoma have been less thoroughly investigated in comparison with angiogenesis. The aim of this study was to evaluate the role of lymphangiogenesis as a prognostic factor in renal cell carcinoma (RCC).
  
  
  METHODS
  The expression of peritumoral/intratumoral lymphatics was studied by immunohistochemical methods in paraffin-embedded nephrectomy specimens from 133 patients with clear cell carcinoma. Patients were divided into 3 groups depending on postoperative follow-up: I) patients without metastases, II) patients with metastases during follow-up, and III) patients with metastases during the operation. Peritumoral lymphatics (PTL) and intratumoral lymphatics (ITL) were immunostained with a D2-40 antibody.
  
  
  RESULTS
  The mean number of PTL present in each group was I=14.1, II=10.6, III=12.1. The mean number of ITL present in each group was I=0.7, II=2.3, III=2.3. The 3 groups showed statistically significant differences only in the case of ITL. A mean count of ITL ≥1 is significantly associated with an increased risk of regional lymph node involvement and distant metastasis. Patients with expression ITL >0.2 and PTL ≤15.2 had a significantly shorter cancer-specific survival.
  
  
  CONCLUSIONS
  The number of ITL showed an association with more aggressive cases of RCC and progression of disease. Therefore, the level of expression ITL, together with stage and histological grading, may provide valuable predictive information about the outcome of treatment.
authors.affiliation: Clinic of Urology and Oncological Urology, Wrocław Medical University, Wrocław, Poland. debinski@gmail.com
authors.forename: Paweł
authors.initials: P
authors.lastname: Dębiński
authors.forename: Janusz
authors.initials: J
authors.lastname: Dembowski
authors.forename: Paweł
authors.initials: P
authors.lastname: Kowal
authors.forename: Tomasz
authors.initials: T
authors.lastname: Szydełko
authors.forename: Anna
authors.initials: A
authors.lastname: Kołodziej
authors.forename: Bartosz
authors.initials: B
authors.lastname: Małkiewicz
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Tupikowski
authors.forename: Romuald
authors.initials: R
authors.lastname: Zdrojowy
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000401:mortality / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000401:mortality / Q000503:physiopathology*; D042583:Lymphangiogenesis; D042601:Lymphatic Vessels / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011044:Poland / Q000453:epidemiology; D015996:Survival Rate