Surgeons treating children and young adults with a rare family of cancers called non-rhabdomyosarcoma soft tissue sarcomas have long faced an uncomfortable trade-off. Removing a tumor with a wide cuff of surrounding healthy tissue has been the traditional safeguard against cancer returning at the surgical site, but in a child’s smaller body, that extra centimeter or two can cost nerves, blood vessels, tendons and even joints, with lasting consequences for function and quality of life. A new large prospective clinical trial now reports that, in this disease, control may be achieved with far narrower margins than surgeons have historically aimed for, potentially sparing young patients significant tissue loss without raising the risk of local recurrence.
The study, led by researchers at UC Davis and conducted by the Children’s Oncology Group as trial ARST0332, was published in JAMA Surgery. According to the findings, close surgical margins as small as one millimeter, less than one tenth of the traditionally recommended margin, were associated with a low risk of the cancer returning at the surgical site. Until now, the researchers note, surgeons have had no scientific evidence on the optimal surgical margins for pediatric patients with non-rhabdomyosarcoma soft tissue sarcomas, making this the first large prospective trial to address the question directly.
Non-rhabdomyosarcoma soft tissue sarcomas, abbreviated NRSTS, include many different types of cancers that start in tissues that normally develop into muscles, nerves and tendons. They account for more than half of soft tissue sarcomas in children and young adults, and every year around 550 new cases are diagnosed in children in the United States alone. The standard treatment is surgery with a complete resection, known as R0, in which the tumor is fully removed with no cancer cells at the microscopic edges of the removed tissue, a so-called negative or cancer-free margin. Traditionally, the recommended protocol has been a margin of one to two centimeters when feasible, but in a child’s smaller body that distance may be difficult to achieve without damaging important structures.
Some patients also need chemotherapy and radiation therapy, depending on the type of cancer, its size and grade, and whether it can be completely removed; the objective of those additional treatments is to prevent the cancer from returning. The new trial evaluated the risk of local cancer recurrence after surgical and chemoradiation therapies for non-metastatic NRSTS in children and young adult patients. The researchers assessed the impact of margin extent on local recurrence and survival outcomes in 266 patients, all under the age of 30 with a median age of 13.7 years. Every patient in the study had their tumor completely removed with no cancer cells at the margins. Of the 266 patients, 178 received surgery alone, while the other 88 also received chemotherapy and radiation, either before or after surgery.
The team reviewed the patients’ diagnostic imaging, tumor biopsies and resection specimens, and operative records, and followed the patients for a median of 6.2 years. They classified the cohort into three groups: a low-risk group treated with surgery and no other treatment; an intermediate-risk group that received upfront surgery followed by chemoradiation; and an intermediate-risk group that received upfront chemoradiation followed by surgery. This design allowed the investigators to examine how margin width related to local recurrence across different treatment intensities and risk categories.
Exact margin widths were available for 132 patients, about half of those studied. In this subgroup, the estimated risk of cancer returning at the surgical site within five years was 4.9 percent with a one-millimeter margin, 2.0 percent with a margin of two to five millimeters, and zero percent with a margin of six millimeters or more. Notably, the five-year local recurrence estimate for the narrowest margins was not higher than for wider ones in this dataset, which is the core of the trial’s message: getting within a millimeter of the tumor while still achieving a cancer-free margin appeared compatible with low rates of local return of the disease.
Senior author R. Lor Randall, a UC Davis Health orthopedic surgeon who specializes in pediatric oncology, framed the clinical dilemma that motivated the research. “When we remove a tumor, our goal is to leave no cancer behind. So, when we operate on a child or young adult with soft tissue sarcomas, we ask how surgically aggressive we need to be in obtaining this negative margin?” he said. Randall, who holds The David Linn Endowed Chair for Orthopaedic Surgery and chairs the Department of Orthopaedic Surgery at UC Davis Health, added that the stakes of margin width are uniquely high in young patients: “For a child, a few millimeters can make a lifelong difference when a tumor is next to an important nerve or blood vessel.”
“For the first time, we have evidence from a large prospective trial to help answer how closely we can safely get to these tumors,” Randall said. “So, it is very exciting to find that getting close to the tumor, within a millimeter, can potentially save a blood vessel or healthy tissue and meet the standard of care, something that had never been shown before.” The study also examined recurrence risk by treatment group rather than margin width alone. With surgery and no chemoradiation treatment, the risk of local return of cancer was 5.6 percent for patients with smaller tumors. For patients with large tumors who received chemotherapy, the risk of local recurrence was 3.7 percent. Randall explained that most smaller tumors, those under five centimeters, do well with close margins even without chemotherapy and radiation, while larger tumors, above five centimeters, would likely require chemotherapy and radiation. He also noted that wider margins may be more important for patients treated with surgery alone, a nuance that underscores that the findings do not eliminate the role of margin judgment in every clinical scenario.
“These findings can help surgeons decide when a close, but cancer free margin may be enough, allowing them to preserve more of a young person’s limb and its function,” said Sheri Spunt, coauthor and principal investigator on the trial. Spunt was an endowed professor of pediatric cancer at Stanford University and is now a senior medical director at AbbVie. The researchers emphasized, however, that decisions about surgical margins require a team experienced in treating these rare cancers. Such decisions must weigh the type and behavior of the tumor, nearby structures such as nerves and blood vessels, and whether chemotherapy or radiation are needed. “Children with these rare cancers should be cared for at centers with extensive experience treating pediatric sarcoma,” Randall said. “They need access to pediatric oncologists, radiation therapists and surgeons who meet regularly to plan their care.”
The study, whose first and corresponding author is Susan M. Hiniker of Stanford University, was funded by St. Jude Children’s Research Hospital through grants P01CA23099 and P30CA21765, and by the National Institutes of Health to the Children’s Oncology Group through grants U10CA098543, U10CA098413, U10CA29511, U10CA180803, U10CA180886 and U10CA180899. It was also supported by the St. Baldrick’s Foundation, the Seattle Children’s Foundation from Kat’s Crew Guild via the Sarcoma Research Fund, and the American Lebanese Syrian Associated Charities. The investigators reported no conflicts of interest. As the largest prospective trial to evaluate surgical margins in relation to the risk of cancer recurrence in this population, the study offers the first prospective evidence that margins far smaller than the traditional one to two centimeters, when cancer-free, were associated with low five-year local recurrence estimates in children and young adults with non-metastatic non-rhabdomyosarcoma soft tissue sarcomas, a result that may reshape how surgeons balance completeness of resection against preservation of healthy tissue in young patients.
Subject of Research: Surgical margin width and local recurrence risk in pediatric and young adult non-rhabdomyosarcoma soft tissue sarcoma
Article Title: Wider surgical margins may not mean better cancer control, finds large-scale treatment trial
Article References: Wider surgical margins may not mean better cancer control, finds large-scale treatment trial. Original publication (Bibliographic details unavailable.)
Image Credits: AI Generated
DOI: Not provided
Keywords: pediatric sarcoma, surgical margins, non-rhabdomyosarcoma soft tissue sarcoma, local recurrence, Children's Oncology Group, JAMA Surgery, cancer surgery, chemoradiation, limb preservation, clinical trial, UC Davis, oncology
News Source: Nathaniel Bowman. (October 28, 2026). Close Surgical Margins May Suffice in Pediatric Sarcoma Trial. Scienmag.
