Modifier 22 Use in Fee-for-Service Medicare.

Importance: Modifier 22 is a mechanism designed for surgeons to identify cases that are more complex than their Current Procedural Terminology code accounts for. However, empirical studies of the use and efficacy of modifier 22 are lacking. Objective: To assess the use of modifier 22 in common surgical procedures and the association of use with compensation. Design, Setting, and Participants: This was a cross-sectional analysis of the 2021 Physician/Supplier Procedure Summary Limited Data Set including all Part B carrier and durable medical equipment fee-for-service claims. Claims for 10 common surgical procedures were evaluated, including mastectomy, total hip arthroplasty, total knee arthroplasty, coronary artery bypass grafting, laparoscopic right colectomy, laparoscopic appendectomy, laparoscopic cholecystectomy, kidney transplant, laparoscopic total abdominal hysterectomy and bilateral salpingo-oophorectomy, and lumbar laminectomy. Data were analyzed from August to November 2023. Main Outcomes and Measures: Rate of modifier 22 use, rate of claim denial, mean charges, mean payment for accepted claims, and mean payment for all claims. Results: The sample included 625 316 surgical procedures performed in calendar year 2021. The proportion of modifier 22 coding for a procedure ranged from 5725 of 251 521 (2.3%) in total knee arthroplasty to 1566 of 18 459 (8.5%) in laparoscopic total abdominal hysterectomy and bilateral salpingo-oophorectomy. Submitted charges were 11.1% (95% CI, 9.1-13.2) to 22.8% (95% CI, 21.3-24.3) higher for claims with modifier 22, depending on the procedure. Among accepted claims, those with modifier 22 had increased payments ranging from 0.8% (95% CI, 0.7-1.0) to 4.8% (95% CI, 4.5-5.1). However, claims with modifier 22 were more likely to be denied (7.4% vs 4.0%; P < .001). As a result, overall mean payments were mixed, with 4 procedures having lower payments when modifier 22 was appended, 4 procedures having higher payments with modifier 22, and 2 procedures with no difference. The largest increase in mean payment for modifier 22 claims was for kidney transplant with an increased payment of $71.46 (95% CI, 55.32-87.60), which translates to a relative increase of 3.4% (95% CI, 2.9-4.6). Conclusions and Relevance: The findings in this study suggest that modifier 22 had little to no financial benefit when appended to claims for a diverse panel of surgical procedures. In the current system, surgeons have little reason to request modifier 22, and no mechanisms currently exist for surgeons to recoup payment for difficult operations.

Mutant p53R175H promotes cancer initiation in the pancreas by stabilizing HSP70.

Pancreatic cancer remains a highly lethal malignancy. We have recently shown that simultaneous expression of Kras and mutant Tp53R175H promotes invasive ductal adenocarcinoma from pancreatic ductal cells. We hypothesized specific mutations in TP53 have divergent mechanisms of transforming ductal cells. In order to understand the role of mutant TP53 in transforming pancreatic ductal cells, we used a lentiviral system to express mutant TP53R175H and TP53R273H, two of the most frequently mutated TP53 alleles in pancreatic cancer patients, in immortalized, but not transformed, pancreatic ductal epithelial cells carrying a KRAS mutation (HPNE:KRASG12D). Mutant TP53 expression enhanced colony formation and an RPPA assay results revealed TP53R175H uniquely induced HSP70 expression in HPNE:KRASG12D cells. In the context of TP53R175H expression; we observed nuclear localization of HSP70. We performed immunoprecipitation experiments to show mutant p53R175H binds to HSP70. We also provide evidence mutant p53R175H is important for HSP70 stability and, more importantly, HSP70 is required for mutant p53 stability. These data are critical in the context of events leading to cellular transformation in the pancreas.