Modifier 22 on perioperative outcomes of robotic assisted laparoscopic prostatectomy

Robotic assisted laparoscopic prostatectomy (RALP) is a mainstay in the treatment of prostate cancer. Current procedure terminology (CPT) identifies a case that requires substantially greater effort than usual by using the modifier 22 code (M22). Our objective was to identify the most common etiologies leading to M22 at our institution and determine the effect on perioperative outcomes.

We retrospectively reviewed our prostatectomy database from 2009-2012 to identify patients who underwent RALP with and without M22. Reasons for M22 were determined by review of operative reports. Comparisons were made using Chi-square analysis and independent t-tests for continuous data.

Of 579 patients identified from our database, 208 (36%) had a M22. Eighty-six (41%) patients had ≥ 2 documented reasons for M22. Adhesiolysis was the most common reason for M22 followed by large prostate and previous hernia mesh. Body mass index (BMI) (29.8 versus 28), prostate volume (53 g versus 44 g), operative time (259 minutes versus 234 minutes), and discharge from hospital with pelvic drain in place (6.7% versus 3%) were all significantly higher in the M22 group. Final pathological stage and positive margin rate were not increased in those with a M22. Complications were not different between those with and without M22.

The M22 code is associated with longer operative times, larger prostates, and higher BMI. Adverse effects on final pathological stage, margin status and complications were not found in those with M22. Many patients with a M22 have more than one reason documented as for the explanation of the modifier.