Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT05776667 |
Other study ID # |
103725 |
Secondary ID |
|
Status |
Recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
August 15, 2023 |
Est. completion date |
March 30, 2026 |
Study information
Verified date |
August 2023 |
Source |
Medical University of South Carolina |
Contact |
Alan Brisendine |
Phone |
843-792-9007 |
Email |
brisend[@]musc.edu |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
This study is investigating the feasibility of preoperative 5-day hypofractionated
radiotherapy (HFRT) for extremity soft tissue sarcoma (STS). The primary objective is to
assess the uptake of 5-day HFRT in patients with STS who are candidates for preoperative
radiotherapy and limb preserving surgery. Secondary objectives include evaluation of the
rates of favorable pathologic response, major wound complications, local control, acute
toxicity, and 1-year late toxicity will be assessed. Exploratory objectives include
evaluation of the impact of preoperative 5-day HFRT on access to care, the socio-demographic
profile of the trial participants will be compared to that of extremity STS patients seen
within Hollings Cancer Center (HCC) and recommended preoperative conventional fractionation
radiotherapy (CFRT) in the 3 years prior to the study opening. The retention rate for
radiotherapy at HCC in patients meeting trial criteria during the prior 3 years will be
compared with the retention rate for radiotherapy during the study period. An exploratory
analysis will measure serum SFRP2 pre- and post- radiotherapy to assess changes in response
to preoperative 5-day HFRT. Changes in serum SFRP2 will be evaluated for association with a
favorable pathologic response to determine the potential of serum SFRP2 as a predictive
biomarker. Patient satisfaction with the decision to participate in a trial of preoperative
5-day HFRT will be assessed.
Description:
The current standard approach to the management of extremity STS is a combination of
radiotherapy and limb preserving surgery. Currently guidelines recommend preoperative
conventionally fractionated radiotherapy (CFRT) given at 1.8-2.0 Gy/fx, which involves 5-6
weeks of daily treatments. Preoperative hypo-fractionated radiotherapy (HFRT) is an approach
that can shorten the duration of treatment. Clinical outcomes with preoperative HFRT in STS
have been reported from retrospective case series, prospective institutional registries and
phase I-II trials. However, preoperative HFRT has not been compared in a prospective
randomized trial to CFRT and due to the rarity of extremity soft tissue sarcoma, attempts to
develop such a trial would face feasibility challenges. Therefore, single arm trials of
preoperative HFRT will be critical to defining the feasibility, toxicity, efficacy, and
potential improvement in access to care associated with this approach.
Radiation therapy combined with wide local excision in the preoperative or postoperative
setting optimizes local control for extremity STS. Preoperative radiotherapy confers a higher
rate of wound complications but a lower rate of irreversible sequela such as fibrosis and
lymphedema compared with postoperative radiotherapy. Resultantly, preoperative radiotherapy
is the preferred approach in most cases. Preoperative radiotherapy with CFRT given at 1.8-2.0
Gy/fx, involves 5-6 weeks of daily treatments. The burden of daily travel and time away from
work or care giving can be a barrier to utilization of radiotherapy. A recent analysis of the
National Cancer Database demonstrated that farther distance to treatment was a negative
predictor for receipt of radiotherapy in extremity STS. Sociodemographic factors such as
female sex, older age (>70 years), Black race, and noncommercial insurance coverage were also
negatively associated with receipt of radiotherapy. The authors summarized that radiotherapy
is underutilized in the treatment of STS and that sociodemographic disparities exist in
access to radiotherapy. Receipt of radiation therapy and surgery within a high volume (HV)
sarcoma center has been associated with improved overall survival, while Black race and
non-metropolitan residents were negative predictors for treatment within such centers. To
address disparities in access to radiation therapy, the American Society for Radiation
Oncology Committee on Health Equity, Diversity, and Inclusion has proposed studying novel
HFRT schedules. As validation of this strategy, Kalbasi et al. increased retention of
extremity STS patients within a HV sarcoma center by 3-fold with the utilization of
preoperative HFRT. Further, the decreased time and travel associated with HFRT, can address
an established barrier to clinical trial participation, particularly for those living remote
from clinical trial sites. Clinical trial participation is particularly low in rural areas
which results in these populations being underrepresented in the clinical research. A survey
of South Carolina based medical researchers, identified rural residents as a group that are
difficult to find and recruit to clinical trials. In a survey of urban and rural South
Carolina residents, there was no difference in reported willingness to participate in
clinical trials, but rural residents were more likely to perceive limited access to clinical
trial sites. Investigating cancer treatment approaches that decreased the economic and
logistical burdens incurred by patients, such as preoperative 5-day HFRT, may increase
clinical trial participation by rural South Carolina residents and ultimately address
disparities in representation of these populations in cancer research.
HFRT, using >2.2 Gy/fx, has resulted in equivalent oncologic outcomes to CFRT in other tumor
sites such as breast, prostate and rectum. For STS, HFRT may confer a radiobiologic advantage
in that the linear-quadratic model predicts larger doses per fraction provide better tumor
control for tumors with a lower α/β ratio. For liposarcomas and rhabdomyosarcomas, their α/β
ratio (~4 Gy) is similar to breast and prostate cancer, malignancies in which HFRT has been
widely adopted. While histologic variability certainly exists, most STSs have estimated α/β
ratios lower than 10, suggesting increased sensitivity to larger fraction size.
Clinical outcomes with preoperative HFRT in STS have been reported from retrospective case
series, prospective institutional registries and phase I-II trials. Comparing oncologic
outcomes across these series is hindered by heterogeneous clinicopathological features,
surgical techniques, samples sizes, and radiation fractionation schedules. However, the local
control and rates of wound complications associated with HFRT and CFRT regimens appear
similar as summarized Spalek and Rutkowski.
This study will utilize a 30Gy/5fx preoperative regimen as it has an estimated EQD2 of 50 Gy
(based on a α/β ratio=4) and therefore would be expected to closely parallel the biologic
effect of CFRT. This preoperative 5-day HFRT regimen was studied in a phase II trial at UCLA
and the 2-year rates of acute wound complications were favorable compared to historical
controls.
Exploratory Analysis of SFRP2 as a Predictive Biomarker:
Secreted Frizzled-Related Protein 2 (SFRP2) is a secretory protein involved in activation of
the Wnt signaling pathway. Wnt signaling regulates normal embryonic development but
aberrations in this pathway have been linked with tumor progression. SFRP2 is a tumor
promotor that which exerts effects on endothelial cells, tumor cells and T-cells. SFRP2 has
been shown to stimulate angiogenesis in endothelial cells through activation of the
non-canonical Wnt/Ca2 pathway. SFRP2 mediated activation of the Wnt/Ca2 pathway results in
downstream dephosphorylation of the nuclear factor of activated T-cells (NFAT). NFAT then can
translocate from the cytoplasm to the nucleus where it mediates processes involving tumor
cell growth, survival, invasion, and angiogenesis. Inhibition of SFRP2 has been shown to
inactivate NFAT in tumor cells and imped tumor cell migration. NFAT also is involved in
regulation of T-cell activity. SFRP2 has been shown to promote NFATc3, CD38 and PD-1
expression in T-cells, which are mechanisms for immunotherapeutic resistance. Monoclonal
antibodies to SFPR2 in an osteosarcoma model lowered serum SFPR2 levels, lowered CD38 levels
in tumor-infiltrating lymphocytes and T-cells and lowered PD-1 levels in T-cells.
SFRP2 has been identified as a tumor promotor in multiple histological subtypes of STS. In
mouse angiosarcoma models, a humanized monoclonal antibody to SFRP2 has been shown to lower
serum levels of the protein and inhibit tumor proliferation.
In humans with breast cancer, serum SFRP2 levels are elevated over healthy controls and
correlate with increasing tumor size, presence of lymph node metastasis, increasing TMN stage
and higher Ki67, a marker of proliferation.
In humans with STS, the levels of serum SFRP2 expression and the response of serum SFRP2
levels to therapeutic interventions such as radiotherapy are unknown. This study will compare
serum levels of SFRP2 before and after preoperative 5-day HFRT to define levels of expression
in patients with STS and assess the effect of radiotherapy on SFRP2 expression. Further, we
will evaluate the association of the change in serum SFRP2 levels with extent of tumor
fibrosis/hyalinization, a histologic predictor of oncologic outcome, to determine the
potential of SFRP2 as a predictive biomarker for favorable pathologic response. If a
preoperative predictive biomarker were established in STS, then it potentially could be
utilized to intensify neoadjuvant therapies.