Prostate cancer pathologic stage pT2b (2002 TNM staging system): does it exist?

OBJECTIVE

In the 1997 TNM staging system, tumors were classified into a single subdivision: T2a, and bilateral tumor involvement (T2b). In the 2002 TNM staging system, tumors are subclassified as T2a (less than one half of one lobe involvement), T2b (more than one half of one lobe involvement), and T2c (bilateral involvement). A recent study questioned the existence of a true pathologic pT2b tumor. The aim of our study is to verify this question.

MATERIALS AND METHODS

The study population consisted of 224 men submitted to radical retropubic prostatectomy. The surgical specimens were histologically evaluated by complete embedding and whole-mount processing. Tumor extent was evaluated by a point-count method. The surgical specimens were staged according to the 2002 TNM staging system.

RESULTS

Using the 2002 TNM criteria, the surgical specimens were classified as pT2a, 28 (12.50%); pT2b, 0 (0%); pT2c, 138 (61.61%); pT3a, 30 (13.39%); and, pT3b, 28 (12.50%). Using the point-count method for tumor extent evaluation, the minimum and maximum total points obtained in unilateral tumors were 192 and 368 points, respectively; the most extensive unilateral tumor showed 68 positive points (less than half the minimum total point-count).

CONCLUSIONS

Using the point-count method for tumor extent, our study questions a real existence for pathologic stage pT2b tumors (unilateral tumors involving greater than one-half of one lobe).