Surgical variables impact bladder cancer outcomes: A cooperative group report

Reviewer: Neha Vapiwala, MD
OncoLink
Last Modified: June 2, 2003

Presenter: H. Herr
Presenter's Affiliation: Southwestern Oncology Group, Intergroup
Type of Session: Scientific

Background

The use of neoadjuvant MVAC (methotrexate, vinblastine, adriamycin, cisplatin) followed by cystectomy was shown to be superior to cystectomy alone in patients with muscle invasive bladder cancer in the SWOG 87-10 (INT-0080) randomized trial (JCO 20:2a, 2001). The MVAC arm had survival rates of 57% vs. 42% with surgery alone, as well as a relative prolongation of median surival by over 2 years. As the quality of surgery is an important but heterogeneous variable, this retrospective analysis evaluated the effect of various surgical factors on patient outcomes.

Materials and Methods

Data review on 307 pts from 109 different institutions operated on by 106 different surgeons
268 pts underwent radical cystectomy as primary treatment; of the 39 who did not, 13 refused, 22 had disease spread, and 4 had progressive disease
Primary endpoints were 5-yr overall survival (OS) and local recurrence (LR)
Median follow-up = 7.1 yrs
A variety of patient, tumor, and surgical variables were evaluated in this study
Also, treatment arm of MVAC vs. no MVAC was evaluated, with pts matched well between the two arms for all factors EXCEPT for less extravesical disease in MVAC group, possibly a result of MVAC downstaging effect itself

Results

On multivariate analysis, margin status and number of nodes removed were statistically significant predictors for both post-cystectomy survival and local recurrence
Benefit of removing 10+ nodes was seen in both node-postive and node-negative patients.
Lower mortality rates seen in pts receiving MVAC + cystectomy + PLND of 10+ nodes vs. cystectomy alone (33% vs. 47%).
Of 25 pts with positive margins, all recurred and died of disease.
Of 26 pts with unknown margins, majority recurred and died of disease.

Author's Conclusions

Surgical variables significantly associated with post-cystectomy survival and local recurrence rates are margin status and number of pelvic lymph nodes removed.
Patients with negative margin status and 10 or more nodes removed had longer post-cystectomy survival and lower local recurrence.
These associations with outcomes did not differ by the presence or absence of chemotherapy.
Future combined modality surgery and chemotherapy studies in muscle-invasive bladder cancer patients should factor in the surgical margin status and extent of lymph node removal.

Clinical/Scientific Implications

It is generally accepted that the quality of oncologic surgery is probably directly related to the expertise of the operating surgeon. A more experienced surgeon is likely to have better outcomes both with respect to efficacy/cure as well as postoperative complications and mortality. This retrospective review identified two particular surgical parameters with a positive effect on survival and local control: negative surgical margins and thorough lymph node resection. It is interesting to note that the benefit of this second variable was seen in both node negative patients as well as node positive. One way to interpret this is that number of nodes removed is perhaps a surrogate for better surgery. This might be particularly true in bladder cancer surgery, where more extensive lymph node removal has been associated with cleaner surgical margins and lower recurrence rates independent of tumor stage. What is not addressed by this review is the role of the pathologist in identifying nodes and determining their status, most certainly a critical component of cancer staging and thus outcome.

Oncolink's ASCO Coverage made possible by an unrestricted Educational Grant from Bristol-Myers Squibb Oncology.