U.S. researchers at Moffitt Cancer Center in Tampa, Florida, working with colleagues in Sweden, the Netherlands, and Puerto Rico, have validated a radiosensitivity molecular signature that could lead to better radiation therapy decisions for patients with breast cancer.
The study, published online 25 July in Clinical Cancer Research, included more than 500 patients who had been treated at Erasmus Medical Center in Rotterdam or Karolinska University Hospital in Stockholm. The results demonstrated that a radiosensitivity molecular signature could predict clinical outcomes in patients treated with radiation therapy, according to the researchers.
The signature had previously been tested and validated for rectal, esophageal, and head and neck cancers. It was developed based on gene expression for 10 specific genes by identifying biomarkers for cellular radiosensitivity, according to a team led by Steven Eschrich, PhD, director of Moffitt's Biomedical Informatics Core.
The test predicted radiosensitivity in 159 patients in the Karolinska database, who had improved five-year relapse-free survival, at 95%, compared with 75% five-year relapse-free survival for patients predicted to be radioresistant. No difference was observed between radiosensitive and radioresistant patients who did not undergo radiation therapy (71% versus 77%, respectively), as expected because the signature is radiotherapy specific.
Similar results were found in the 344 patients in the Erasmus database. Radiosensitive patients who received radiotherapy had improved five-year metastasis-free survival, at 77%, compared with 64% for the radioresistant patients. Once again, outcomes were comparable for radiosensitive and radioresistant patients who did not receive radiotherapy, at 80% and 81%, respectively.
Approximately 60% of all cancer patients receive radiation therapy during their treatment; however, no molecular diagnostic or biomarker of radiosensitivity had been developed to predict its benefit until now, according to co-author Dr. Javier Torres-Roca, a radiation oncologist and member of Moffitt's experimental therapeutics program.
"We propose that [radiosensitivity molecular signature] is a predictive biomarker of radiation therapy therapeutic benefit for patients with breast cancer," he said in a statement. "This novel biomarker provides an opportunity to integrate individual tumor biology with clinical decision-making in radiation oncology."
The radiosensitivity molecular signature technology is owned by Moffitt and has been licensed to cancer molecular diagnostics company CvergenX.
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnieeurope.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&fit=crop&h=100&q=70&w=100)
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnieeurope.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)
