A new radiation therapy technique has been proved effective for treating patients with head and neck cancers who have low hemoglobin levels, according to research presented at the European Society for Radiotherapy and Oncology (ESTRO) annual meeting being held this week in Barcelona, Spain.
Patients with low hemoglobin levels tend not to respond well to radiotherapy. As a result, both local control and disease-free survival may be compromised. Researchers from the Netherlands have discovered that the use of accelerated radiotherapy with carbogen and nicotinamide (ARCON) may help such patients.
The treatment combines the water-soluble vitamin nicotinamide and carbogen, a mixture of carbon dioxide and oxygen, with accelerated radiotherapy. When carbogen is inhaled, the increased level of carbon dioxide causes the brain to react to potential suffocation, because it interprets the increase in carbon dioxide in the blood as a decrease in oxygen level. The body compensates by reducing hypoxia, a lack of oxygen in bodily tissues. The addition of nicotinamide also reduces hypoxia by increasing blood flow.
Accelerated radiotherapy to counteract tumor cell repopulation during radiotherapy, combined with carbogen and nicotinamide administered immediately before irradiation to increase oxygen levels, ensures that adaptive mechanisms cannot erode the effect of this treatment, Dr. Hans Kaanders, professor of translation radiation oncology at Radboud University Nijmegen Medical Center, told ESTRO attendees on Thursday. He said that the ARCON therapy regime is the first to show a positive effect in patients with low hemoglobin levels.
Kaanders reported the outcomes of a 345-patient randomized clinical trial in which 174 patients with squamous cell laryngeal cancer received only accelerated radiotherapy of two fractions per day during the last week of treatment. The remaining 171 patients had ARCON therapy.
Patients who had normal hemoglobin levels before conventional radiotherapy had significantly better outcomes than those with low hemoglobin levels. They had better control of the cancer at its primary site (76% compared to 56%), disease-free survival (72% compared to 48%), and metastasis-free survival (90% compared to 70%).
"However, when we looked at the ARCON group, in cases where the patients had low [hemoglobin] levels before treatment, we found that ARCON improved control of the cancer at its primary site, and improved disease-free and metastasis-free survival, so that the differences between them and patients with normal [hemoglobin] levels were no longer significant," said Dr. Geert Janssens, also from Radboud University Nijmegen.
For example, when the low-hemoglobin ARCON patients were compared with the normal-hemoglobin radiotherapy group, the difference in local control was only 1% (81% versus 82%, respectively), the group noted.
![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)
