Lymph Node Staging in Bladder Cancer – Is Pathologic Evaluation of Microscopic Lymph Nodes Necessary for Adequate Staging?
Kumaran Mudaliar, Lu Wang, Vikas Mehta, Guliz Barkan, Maria Picken. Loyola University Medical Center, Maywood, IL
Background: There is an emphasis on lymph node (LN) dissection in bladder cystectomy for staging, prognosis, and management. However, little data exists on the proper techniques for pathologic examination and LN staging. The adequacy of nodal pathologic evauation has not been standardized.
Design: We retrospectively reviewed 249 cystectomies in correlation with the gross descriptions and evaluated for number of grossly identified versus microscopically identified LNs. The LNs were grouped into 3 categories: primary drainage ("regional nodes"), secondary drainage sites ("common iliac LNs"), and extra-regional nodes according to the 7th edition of the cancer staging manual. The cases with positive LNs were evaluated for location of positive nodes and whether the positive nodes were grossly or microscopically identified.
Results: In all, 8,376 LNs were recovered (see table below). Of these LNs, 4.690 were grossly identified and 2,814 LNs were microscopically identified. In all, 62 cases had positive LNs with 1,100 total LNs. In the primary regional LNs, 189/611 (30.9%) gross LNs were postive and no microscopic LNs (n=195) were positve. In the common iliac LNs, 56/126 (44.4%) gross LNs were positive for metastasis and only 1/45 (2.2%) of microscopic LNs was positive (1/2,814 [0.03%] of all microscopic LNs. In the extra-regional LNs, 32/69 (46.4%) gross LNs were positive and no microscopic LNs (n=54) were positive. In the positive cases, involved LNs ranged in number from 1-15 with an average of 3.71. The total number of LNs recovered in positive cases ranged from 5-112 with an average of 32.89 LNs. In a single case with microscopic node positive, there was advanced nodal disease and the final pN was not affected.
Conclusions: It is an open question if recovery of microscopic LNs should be undertaken and included in the pathologic nodal staging. Although microscopic evaluation of the entire perinodal adipose tissue increased the yield of LNs, there was no significant increase in the number of positive LNs and the final pN status was not affected. While the size of the largest tumor deposit and extranodal extension may independently impact survival, there is no data on the impact of the size of the involved LN and the method of their recovery.
Category: Genitourinary (including renal tumors)
Monday, March 4, 2013 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 146, Monday Morning