Researchers conducting a cost-utility analysis of sentinel lymph node (SLN) mapping and lymph node dissection (LND), both selective and routine, for low-risk endometrial carcinoma (clinical stage 1 disease with grade 1-2 endometrioid histology on preoperative endometrial biopsy), found that the SLN mapping had the lowest costs and the highest quality-adjusted survival of the three strategies.
Between the two strategies of LND, selective LND based on intraoperative frozen section was more cost-effective than routine LND.
The researchers created a model using data from past studies and clinical estimates. “Our biggest assumption was that sentinel lymph node mapping is associated with a decreased risk of lymphedema compared with lymph node dissection ... [from] several studies showing that having less than five lymph nodes excised was associated with a much smaller risk of developing lymphedema,” wrote Rudy S. Suidan, MD, of the MD Anderson Cancer Center, Houston, and his coauthors. Lymphedema was the main factor affecting quality of life in the analysis.
The analysis included estimates of rates of lymphadenectomy, bilateral mapping, and unilateral mapping, 3-year disease-specific survival, and overall survival, all of which were compared with third-party reimbursement costs at 2016 Medicare rates.
SLN mapping cost $16,401 per patient, while selective LND cost $17,036 per patient and routine LND cost $18,041 per patient. These strategies had quality-adjusted life years of 2.87, 2.81, and 2.79, respectively.
The superior cost-effectiveness of SLN mapping held, even when the researchers altered several of the variables in the model, including assuming open surgery instead of minimally invasive, and altering the assumed risk of lymphedema.
In addition to the possible limitation of making assumptions about SLN mapping and lymphedema, the researchers also pointed to the 3-year survival rates as shorter-term than preferable, driven by the available literature. The quality-adjusted life years did not differ much between the strategies because “most patients with low-risk cancer tend to have good clinical outcomes,” they wrote.
“This adds to the body of literature evaluating the clinical benefits of this strategy and may help health care providers in the decision-making process as they consider which approach to use,” the researchers wrote.
Dr. Suidan is supported by an NIH grant. Three coauthors reported other grants and fellowships. Five coauthors reported research support from AstraZeneca, Bayer, Clovis Oncology, and several other companies.
SOURCE: Suidan RS et al. Obstet Gynecol. 2018 Jun 11;132:52-8.