Radiation-Associated Undifferentiated Pleomorphic Sarcoma is Associated with Worse Clinical Outcomes than Sporadic Lesions.
BACKGROUND
Radiation therapy is used increasingly as a component of multidisciplinary treatment for many solid tumors. One complication of such treatment is the development of radiation-associated sarcoma (RAS). Undifferentiated pleomorphic sarcoma (UPS), previously termed "malignant fibrous histiocytoma" (MFH) is the most common histologic subtype of RAS. This study investigated the clinical outcomes for patients with radiation-associated UPS (RA-UPS/MFH).


METHODS
The study identified 1068 patients with UPS/MFH treated at the authors' institution. Patient and tumor factors were collected and compared. Regression analysis was performed to identify independent predictors of survival. A matched-cohort survival and recurrence analysis was performed for radiation-associated and sporadic UPS/MFH.


RESULTS
The findings showed that RA-UPS/MFH comprised 5.1 % of the UPS population. The median latency to the development of RA-UPS/MFH was 9.3 years. The 5-year disease-specific survival (DSS) was 52.2 % for patients identified with RA-UPS/MFH (n = 55) compared with 76.4 % for patients with unmatched sporadic UPS/MFH (n = 1,013; p < 0.001). A matched-cohort analysis also demonstrated that the 5-year DSS was significantly worse for RA-UPS/MFH (52.2 vs 73.4 %; p = 0.002). Furthermore, higher local recurrence rates were observed for patients with RA-UPS/MFH than for patients with sporadic lesions (54.5 vs 23.5 %; p < 0.001). Radiation-associated status and incomplete resection were identified as independent predictors of local recurrence.


CONCLUSIONS
This study demonstrated worse clinical outcomes for patients with RA-UPS/MFH than for patients with sporadic UPS/MFH. Local recurrence was significantly higher for patients with RA-UPS/MFH, suggesting a unique tumor biology for this challenging disease.
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Sean P
SP
Dineen
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Christina L
CL
Roland
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Rachel
R
Feig
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Caitlin
C
May
Department of Biostatistics, UT MD Anderson Cancer Center, Houston, TX, USA.
Shouhao
S
Zhou
Department of Pathology, Mount Sinai Hospital, New York, NY, USA.
Elizabeth
E
Demicco
Department of Pathology, UT MD Anderson Cancer Center, Houston, TX, USA.
Ghadah Al
GA
Sannaa
Department of Pathology, UT MD Anderson Cancer Center, Houston, TX, USA.
Davis
D
Ingram
Department of Pathology, UT MD Anderson Cancer Center, Houston, TX, USA.
Wei-Lein
WL
Wang
Department of Sarcoma Medical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Vinod
V
Ravi
Department of Radiation Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Ashleigh
A
Guadagnolo
Deparment of Surgery, Sheba Medical Center, Tel Aviv University, Tel Aviv, Israel.
Dina
D
Lev
Department of Surgery, The Ohio State University, Columbus, OH, USA.
Raphael E
RE
Pollock
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Kelly
K
Hunt
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Janice
J
Cormier
Department of Pathology, UT MD Anderson Cancer Center, Houston, TX, USA.
Alex
A
Lazar
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
Barry
B
Feig
Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX, USA. ketorres@mdanderson.org.
Keila E
KE
Torres
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D051677:Histiocytoma, Malignant Fibrous / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D018365:Neoplasm, Residual; D009381:Neoplasms, Radiation-Induced / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D016016:Proportional Hazards Models; D011878:Radiotherapy / Q000009:adverse effects; D015996:Survival Rate; D055815:Young Adult