TY - JOUR
T1 - A novel, simplified, externally validated staging system for truncal/extremity soft tissue sarcomas
T2 - An analysis of the US Sarcoma Collaborative database
AU - and other members of the US Sarcoma Collaborative
AU - Johnson, Aileen C.
AU - Ethun, Cecilia G.
AU - Liu, Yuan
AU - Poultsides, George
AU - Howard, John H.
AU - Bedi, Meena
AU - Charlson, John
AU - Tseng, Jennifer
AU - Roggin, Kevin K.
AU - Votanopoulos, Konstantinos
AU - Cullinan, Darren
AU - Fields, Ryan C.
AU - Maithel, Shishir K.
AU - Cardona, Kenneth
N1 - Publisher Copyright:
© 2018 Wiley Periodicals, Inc.
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Background: The 8th edition AJCC staging system for truncal/extremity soft tissue sarcoma (STS) offers significant changes from the 7th. However the complexity of both limits their clinical utility. Methods: Patients with truncal/extremity STS undergoing resection from 2000 to 2016 at seven institutions of the US Sarcoma Collaborative were analyzed. The proposed staging system was externally validated using the National Cancer Database (NCDB). Results: Of 1318 patients, mean age was 59 years, and 54% were male. Median tumor size was 9 cm; 72% were high grade. Applying 8th edition staging, there was no differentiation between stages IA/IB (P = 0.92), and clinically similar outcomes between stages II/IIIA. Receiver operating characteristic (ROC) analysis identified 7.5 cm as the ideal tumor size discriminating 5-year OS for high-grade tumors. Therefore, a simplified staging system defining all low-grade tumors as stage I, high-grade < 7.5 cm as stage II, high-grade > 7.5 cm as stage III, and metastatic disease as stage IV improved stratification (all P < 0.05). The C-statistic was noninferior to the 8th edition. External validation in the NCDB confirmed optimal stratification (all P < 0.01). Conclusions: Our proposed staging system maintains prognostic significance between stages within a simplified system. For high-grade tumors, a cutoff of 7.5 cm, instead of 5 cm, maintains discrimination for survival and could be a more clinically applicable cutoff for future clinical trials.
AB - Background: The 8th edition AJCC staging system for truncal/extremity soft tissue sarcoma (STS) offers significant changes from the 7th. However the complexity of both limits their clinical utility. Methods: Patients with truncal/extremity STS undergoing resection from 2000 to 2016 at seven institutions of the US Sarcoma Collaborative were analyzed. The proposed staging system was externally validated using the National Cancer Database (NCDB). Results: Of 1318 patients, mean age was 59 years, and 54% were male. Median tumor size was 9 cm; 72% were high grade. Applying 8th edition staging, there was no differentiation between stages IA/IB (P = 0.92), and clinically similar outcomes between stages II/IIIA. Receiver operating characteristic (ROC) analysis identified 7.5 cm as the ideal tumor size discriminating 5-year OS for high-grade tumors. Therefore, a simplified staging system defining all low-grade tumors as stage I, high-grade < 7.5 cm as stage II, high-grade > 7.5 cm as stage III, and metastatic disease as stage IV improved stratification (all P < 0.05). The C-statistic was noninferior to the 8th edition. External validation in the NCDB confirmed optimal stratification (all P < 0.01). Conclusions: Our proposed staging system maintains prognostic significance between stages within a simplified system. For high-grade tumors, a cutoff of 7.5 cm, instead of 5 cm, maintains discrimination for survival and could be a more clinically applicable cutoff for future clinical trials.
KW - neoplasm staging
KW - prognosis
KW - retrospective studies
KW - sarcoma
KW - survival analysis
UR - http://www.scopus.com/inward/record.url?scp=85053921013&partnerID=8YFLogxK
U2 - 10.1002/jso.25239
DO - 10.1002/jso.25239
M3 - Article
C2 - 30261111
AN - SCOPUS:85053921013
SN - 0022-4790
VL - 118
SP - 1135
EP - 1141
JO - Journal of surgical oncology
JF - Journal of surgical oncology
IS - 7
ER -