Hypofractionated preoperative radiotherapy for high risk soft tissue sarcomas in a geriatric patient population

Moderate hypofractionated radiation therapy and pathologic response for soft tissue sarcomas (STS) of limbs and trunk: experience from a tertiary cancer center

BACKGROUND

Preoperative radiation therapy following by limb-sparing or conservative surgery is a standard approach for limb and trunk STS. Data supporting hypofractionated radiotherapy schedules are scarce albeit biological sensitivity of STS to radiation would justify it. We sought to evaluate the impact of moderate hypofractionation on pathologic response and its influence on oncologic outcomes.

MATERIAL AND METHODS

From October 2018 to January 2023, 18 patients with limb or trunk STS underwent preoperative radiotherapy at a median dose of 52.5 Gy (range 49.5-60 Gy) in 15 fractions of 3.5 Gy (3.3-4 Gy) with or without neoadjuvant chemotherapy. A favorable pathologic response (fPR) was considered as ≥ 90% tumor necrosis on specimen examination.

RESULTS

All patients completed planned preoperative radiotherapy. Eleven patients (61.1%) achieved a fPR, and 7 patients (36.8%) a complete pathologic response with total disappearance of tumor cells. Nine patients (47%) developed grade 1-2 acute skin toxicity, and 7 patients (38.8%) had wound complications on follow-up. With a median follow-up of 14 months (range 1-40), no cases of local relapse were observed, and actuarial 3-year overall survival (OS) and distant metastases-free survival (DMFS) are 87% and 76.4%, respectively. In the univariate analysis, the presence of a favorable pathologic response (fPR) was associated with improved 3-year OS (100% vs. 56.03%, p = 0.058) and 3-year DMFS (86.91% vs. 31.46%, p = 0.002). Moreover, both complete or partial RECIST response and radiological stabilization of the tumor lesion showed a significant association with higher rates of 3-year distant metastasis-free survival (DMFS) (83% vs. 83% vs. 56%, p < 0.001) and 3-year overall survival (OS) (100% vs. 80% vs. 0, p = 0.002).

CONCLUSIONS

Preoperative moderate hypofractionated radiation treatment for STS is feasible and well tolerated and associates encouraging rates of pathologic response that could have a favorable impact on final outcomes.

Emerging innovations and advancements in the treatment of extremity and truncal soft tissue sarcomas

In this special edition update on soft tissue sarcomas (STS), we cover classifications, emerging technologies, prognostic tools, radiation schemas, and treatment disparities in extremity and truncal STS. We discuss the importance of enhancing local control and reducing complications, including the role of innovative imaging, surgical guidance, and hypofractionated radiation. We review advancements in systemic and immunotherapeutic treatments and introduce disparities seen in this vulnerable population that must be considered to improve overall patient care.

Meta-analysis of 5-day preoperative radiotherapy for soft tissue sarcoma (5D-PREORTS)

BACKGROUND AND PURPOSE

Although the role of conventionally fractionated radiotherapy (RT) in combination with surgery in the limb-sparing treatment of soft tissue sarcoma (STS) patients is well established, the effectiveness and safety of 5-day preoperative radiotherapy (RT) remain controversial. We performed a meta-analysis to evaluate the treatment outcomes of 5-day preoperative RT using ≥ 5 Gy per fraction with contemporary radiotherapy techniques.

MATERIALS AND METHODS

Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through March 2022 were used to identify eligible studies. Following the PRISMA and MOOSE guidelines, a meta-regression analysis was performed to assess possible correlations between variables and outcomes. A p-value < 0.05 was considered significant.

RESULTS

Nine prospective studies with 786 patients (median follow-up 35 months, 20-60 months) treated with preoperative RT delivered a median total of 30 Gy (25-40 Gy) in 5 fractions. The local control (LC), R0 margins, overall survival (OS), and distant relapse (DR) rates were 92.3% (95% CI: 87---97%), 84.5% (95% CI: 78---90%), 78% (95% CI: 70---86%), and 36% (95% CI: 70---86%). The meta-regression analysis identified a significant relationship between biological equivalent dose (BED) and larger tumor size for LC and R0 margins (p < 0.05). The subgroup analysis reveals that patients receiving BED ≥ 90 (equivalent to 30 Gy in 5 fractions) had a higher LC control rate than BED < 90 (p < 0.0001). The complete pathologic response and amputation rates were 19% (95% CI: 13-26%) and 8.3% (95% CI: 0.5-15%). Amputation rates were higher in studies using the lowest and highest doses and were related to salvage surgery after recurrence and complications, respectively. The rate of wound complication and fibrosis grade 2 or worse was 30% (95% CI 23-38%) and 6.4% (95% CI 1.9-11%).

CONCLUSION

A 5-day course of preoperative RT results in high LC and favorable R0 margins, with acceptable complication rates in most studies. Better local control and R0 margins were associated with regimens using higher BED, i.e., doses equal to or higher than 30 Gy when using 5 fractions.

Leiomyosarcoma of the lower rectum managed by radiotherapy and surgery: A case report and review of literature

Rectal leiomyosarcoma is a very rare entity. Surgery is the main treatment, but the place of radiation therapy remains unclear. A 67-year-old woman was referred for a few-weeks' history of bleeding and anal pain intensified during defecation. Pelvic magnetic resonance imaging (MRI) showed a rectal lesion and biopsies revealed a leiomyosarcoma of the lower rectum. She was free of metastasis on computed tomography imaging. The patient refused radical surgery. After discussion by a multidisciplinary team, the patient received pre-operative long-course radiotherapy followed by surgery. The tumor was treated with 50Gy delivered in 25 fractions, within 5 weeks. The aim of radiotherapy was local control, allowing organ-preservation. Four weeks after radiation therapy, organ-preservation surgery could be performed. She had no adjuvant treatment. At 38-months follow-up, she had no local recurrence. However, distant recurrence (lung, liver, and bone) was detected 38 months after the resection and was managed by intra-venous doxorubicin 60mg/m² and dacarbazine 800mg/m² every 3 weeks. The patient was in a stable condition for nearly 8 months. The patient died 4 years and 3 months after the diagnosis.

Preoperative hypofractionated radiotherapy for soft tissue sarcomas: a systematic review

BACKGROUND

Soft tissue sarcomas (STS) represent a diverse group of rare malignant tumors. Currently, five to six weeks of preoperative radiotherapy (RT) combined with surgery constitute the mainstay of therapy for localized high-grade sarcomas (G2-G3). Growing evidence suggests that shortening preoperative RT courses by hypofractionation neither increases toxicity rates nor impairs oncological outcomes. Instead, shortening RT courses may improve therapy adherence, raise cost-effectiveness, and provide more treatment opportunities for a wider range of patients. Presumed higher rates of adverse effects and worse outcomes are concerns about hypofractionated RT (HFRT) for STS. This systematic review summarizes the current evidence on preoperative HFRT for the treatment of STS and discusses toxicity and oncological outcomes compared to normofractionated RT.

METHODS

We conducted a systematic review of clinical trials describing outcomes for preoperative HFRT in the management of STS using PubMed, the Cochrane library, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Embase, and Ovid Medline. We followed the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Trials on retroperitoneal sarcomas, postoperative RT, and hyperthermia were excluded. Articles published until November 30th, 2021, were included.

RESULTS

Initial search yielded 94 articles. After removal of duplicate and ineligible articles, 13 articles qualified for analysis. Eight phase II trials and five retrospective analyses were reviewed. Most trials applied 5 × 5 Gy preoperatively in patients with high-grade STS. HFRT courses did not show increased rates of adverse events compared to historical trials of normofractionated RT. Toxicity rates were mostly comparable or lower than in trials of normofractionated RT. Moreover, HFRT achieved comparable local control rates with shorter duration of therapy. Currently, more than 15 prospective studies on HFRT + / - chemotherapy are ongoing.

CONCLUSIONS

Retrospective data and phase II trials suggest preoperative HFRT to be a reasonable treatment modality for STS. Oncological outcomes and toxicity profiles were favorable. To date, our knowledge is mostly derived from phase II data. No randomized phase III trial comparing normofractionated and HFRT in STS has been published yet. Multiple ongoing phase II trials applying HFRT to investigate acute and late toxicity will hopefully bring forth valuable findings.