Abstract
Objective: To evaluate the incidence of cervical angiopathy caused by radiation therapy for head and neck cancer. Methods: Segments of 57 cervical arteries were obtained during surgery for head and neck malignant tumors and divided into two groups (irradiated group and non-irradiated group) based on the treatment prior to vascular resection. In order to evaluate vascular injury after radiation therapy, we examined the degree of medial atrophy, medial fibrosis, smooth muscle cell (SMC) differentiation in the media and intima, intimal hyperplasia and endothelial cell (EC) injury. Sections of arterial segments were stained with hematoxylin-eosin, Elastica van Gieson and Masson’s trichrome, and immunohistochemistry for α-smooth muscle actin (α-SMA), smoothelin, S100A4 and CD31 in the resected vessels was conducted. Results: The median interval between the completion of radiation therapy and vascular resection was nine months. No significant differences were observed between the two groups in terms of medial atrophy, medial fibrosis and intimal hyperplasia. The ratio of the smoothelin-positive area per α-SMA-positive area in the media and the S100A4-positive proportion in the intima, indicating the degree of differentiation of the medial SMC and dedifferentiation of the intimal SMC, respectively, showed no significant differences, despite the tendency toward a lower smoothelin-positive area per α-SMA-positive area in the media of the irradiated arteries. The EC coverage revealed on CD31 immunohistochemistry was significantly decreased, with mural thrombus adhesion, in the irradiated group. Conclusions: The ECs of small arteries are damaged by irradiation. Although we did not confirm the statistical significance of medial SMC dedifferentiation, a decreased expression of smoothelin tended to be observed in the media of the irradiated arteries. Our findings provide histopathological evidence of irradiation angiopathy in head and neck cancer and may help to improve the surgical safety of microvascular anastomosis and determine the treatment strategy for head and neck tumors.
Highlights
Radiotherapy and/or chemoradiotherapy are often conducted as the initial treatment for head and neck cancer, with a focus on achieving functional preservation
For the purpose of improving the safety and clinical outcomes of treatment for head and neck cancer, we pathologically evaluated cervical vessels resected during head and neck surgery and examined the influence of irradiation on the cervical vessels
The IR group and non-IR group showed similar medial thickness and fibrosis proportion values (Table 2), a tendency toward a lower smoothelin-positive area per α-smooth muscle actin (α-SMA)-positive area in the media was observed in the IR group (Table 2 and Figure 2)
Summary
Radiotherapy and/or chemoradiotherapy are often conducted as the initial treatment for head and neck cancer, with a focus on achieving functional preservation. In many cases of advanced head and neck cancer, microvascular free tissue transfer is essential for performing functional reconstruction after tumor resection. This technique is reliable for achieving head and neck reconstruction, with a success rate of 90% - 99% [2], necrosis of the transferred tissues, a severe complication of this procedure, may occur in cases involving occlusion of the anastomotic vessels. Immunohistochemistry for α-smooth muscle actin (α-SMA), smoothelin, S100A4 and CD31 was performed to evaluate the incidence of radiation angiopathy. It is known that α-SMA is widely expressed in vascular smooth muscle cells (SMCs) at various degrees of differentiation. For the purpose of improving the safety and clinical outcomes of treatment for head and neck cancer, we pathologically evaluated cervical vessels resected during head and neck surgery and examined the influence of irradiation on the cervical vessels
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Otolaryngology and Head & Neck Surgery
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
