Leiomyosarcoma: One disease or distinct biologic entities based on site of origin?
BACKGROUND
Leiomyosarcoma (LMS) can originate from the retroperitoneum, uterus, extremity, and trunk. It is unclear whether tumors of different origin represent discrete entities. We compared clinicopathologic features and outcomes following surgical resection of LMS stratified by site of origin.


METHODS
Patients with LMS undergoing resection at a single institution were retrospectively reviewed. Clinicopathologic variables were compared across sites. Survival was calculated using the Kaplan-Meier method and compared using log-rank and Cox regression analyses.


RESULTS
From 1983 to 2011, 138 patients underwent surgical resection for LMS. Retroperitoneal and uterine LMS were larger, higher grade, and more commonly associated with synchronous metastases. However, disease-specific survival, recurrence-free survival, and recurrence patterns were not significantly different across the four sites. Synchronous metastases (HR 3.20, P < 0.001), but not site of origin, size, grade, or margin status, were independently associated with worse DSS. A significant number of recurrences and disease-related deaths were noted beyond 5 years.


CONCLUSIONS
Although larger and higher grade, retroperitoneal and uterine LMS share similar survival and recurrence patterns with their trunk and extremity counterparts. LMS of various anatomic sites may not represent distinct disease processes based on clinical outcomes. The presence of metastatic disease remains the most important prognostic factor for LMS.
Department of Surgery, Stanford University Medical Center, Stanford, California.
David J
DJ
Worhunsky
Mihir
M
Gupta
Sepideh
S
Gholami
Thuy B
TB
Tran
Kristen N
KN
Ganjoo
Matt
M
van de Rijn
Brendan C
BC
Visser
Jeffrey A
JA
Norton
George A
GA
Poultsides
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005121:Extremities / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007890:Leiomyosarcoma / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D009367:Neoplasm Staging; D011379:Prognosis; D012186:Retroperitoneal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D015996:Survival Rate; D014594:Uterine Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D055815:Young Adult
leiomyosarcoma; outcome assessment; sarcoma