20 Assessment of Textbook Oncologic Outcomes Following Modified Radical Mastectomy for Invasive Ductal Carcinoma: A Review of the 2004-2017 National Cancer Database

Gabriela L. Aitken, MD¹; Gabriel Correa, MD¹; Shenae Samuels, PhD, MPH¹; Christopher J. Gannon, MD1; Omar H. Llaguna, MD¹

¹Memorial Healthcare System, Hollywood, FL

Background

Textbook oncologic outcome (TOO) is a composite outcome measure attained when all desired shortterm quality metrics are met, following an oncologic operation. The objective of this study was to determine the incidence of TOO and its impact on overall survival (OS) among patients with a diagnosis of invasive ductal carcinoma (IDC) following modified radical mastectomy (MRM).

Design and Methods

The 2004 to 2017 National Cancer Database was queried for patients with nonmetastatic IDC who underwent MRM. The TOO was defined as having attained 5 metrics: resection with negative microscopic margins; American Joint Committee on Cancer compliant lymph node evaluation (n 10); no prolonged length of stay (50th percentile by year); no 30-day readmission; and no 30-day mortality. Categorical variables were analyzed using Pearson’s 2 test or Fisher’s exact test where appropriate. Continuous variables were analyzed using independent t-tests. The OS was defined as the time in months between the date of diagnosis and date of death or last contact. The Kaplan-Meier method with log-rank test was used to compare and estimate OS rates between patients with TOO and patients without TOO (non-TOO).

Results

A total of 75,063 patients were identified, of which 40.8% achieved TOO. The patients with TOO had a lower median age and were more likely to be White, privately insured, and without comorbidities. In terms of facility characteristics, patients with TOO were more likely to be seen in comprehensive community cancer programs with a high case volume per year. Patients with T2, N1, pathologic stage 2, poorly differentiated pathology, and estrogen receptor–positive, progesterone receptor–positive, HER2-negative hormone receptor status were also more likely to have achieved TOO. The TOO group had a higher lymph node yield (TOO, 17.0 ± 6.2 vs non-TOO, 10.6 ± 7.3; P = .000) and higher average number of positive lymph nodes (TOO, 4.1 ± 5.4 vs non-TOO, 2.7 ± 4.5; P = .000). The TOO group had a statistically significant higher median OS compared with the non-TOO group (165.6 vs 142.2 months; P = .000).

Conclusions

The TOO was achieved in approximately 41% of patients undergoing MRM for IDC. Achieving TOO is associated with improved median OS, and therefore, merits further attention in efforts to improve surgical outcomes.