Stroke death in patients receiving radiation for head and neck cancer in the modern era

Temporal trends and risk factors associated with stroke mortality among cancer patients

BACKGROUND

This study aimed to explore the risk of stroke death (SD) in cancer patients, estimate rates, and identify risk factors associated with SD.

METHODS

In this retrospective study, we used the 17 National Cancer Institute Surveillance, Epidemiology, and End Results registries (2000-2020). A total of 5,922,533 patients diagnosed with their first primary cancer were included. The primary outcome was the standardized mortality ratio (SMR) of SD in cancer patients. Secondary outcomes included SD incidence rates and risk factors. Rates were calculated per 100,000 persons with the annual percentage change (APC).

RESULTS

Among included patients, 56,686 (2.0 %) died due to stroke. Compared to the general population, younger patients (≤39 years) (SMR: 2.31) and patients receiving no treatment (SMR: 1.36) had the highest risk. Cancer types with the fastest-declining SD rates were in the male genital (APC: -13.9 %) and breast (APC: -11.8 %). Older age (hazard ratio [HR]: 1.11, p < 0.001), male sex (HR: 1.06, p < 0.001), and non-white race (HR: 1.13, p < 0.001) were associated with increased risk of SD. Cancers of the nervous system (HR: 3.42, p < 0.001), respiratory (HR: 1.38, p < 0.001), and head and neck (HR: 1.37, p < 0.001) had higher risk of SD vs. breast cancer. Patients with primary chemotherapy (HR: 0.69, p < 0.001) and radiotherapy (HR: 0.69, p < 0.001) demonstrated less risk vs. those without treatment.

CONCLUSION

SD has declined over the years for both sexes and all cancer types. Older age, non-white race, and certain cancers (nervous system, respiratory system, and head and neck) pose significant risks for SD.

Effect of delayed treatment on survival of patients with head and neck squamous cell cancer

The impact of prolonged treatment delays on the survival outcomes of patients with head and neck squamous cell cancer (HNSCC) remains controversial. Patients were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The association between diagnosis-to-treatment interval (DTI) and survival was assessed using Cox proportional hazards models and competing risk regression.4700 (6.1%) experienced treatment delays and 28,934 (37.8%) died due to cancer-specific causes. Treatment delays were associated with a worse overall survival (OS) and cancer-specific survival (CSS) of patients with cancer in the lip/oral cavity (OS: adjusted hazard ratio [aHR] = 1.16, 95% confidence interval [CI]: 1.08-1.24; CSS: aHR = 1.15, 95% CI 1.06-1.24), oropharynx (OS: aHR = 1.19, 95% CI 1.12-1.28; CSS: aHR = 1.19, 95% CI 1.10-1.28), and larynx (OS: aHR = 1.21, 95% CI 1.13-1.30; CSS: aHR = 1.21, 95% CI 1.10-1.33). However, treatment delay did not find significance on OS and CSS in patients with cancers of the hypopharynx, nasopharynx, nasal cavity and sinuses, or salivary glands at the time cutoff of 2 months for delayed treatment. Prolonged treatment delays were associated with an increased risk of mortality in patients with lip/oral cavity, oropharyngeal, and laryngeal cancers, and should be focused on in order to improve patient prognosis.

Evolving Role of PET Imaging in Assessing Vascular and Central Nervous System Complications of Radiation Therapy in Head and Neck Cancer

Radiation therapy for head and neck cancer is a cornerstone of treatment but can come with significant and lasting complications. Reduced vascularity and fibrosis heighten the risks of stroke, infection, and diminished quality of life. Advances in imaging technologies, such as fluorodeoxyglucose PET and sodium fluoride-PET, have emerged as critical tools for diagnosing and monitoring vascular inflammation and calcification, enabling earlier interventions and improved patient management. This review examines the pathophysiology of RT-induced damage, with a focus on vascular and connective tissue complications, and highlights the evolving role of PET imaging in early detection and management of these effects.

Neurological complications of modern radiotherapy for head and neck cancer

Radiotherapy is one of the mainstay treatment modalities for the management of non-metastatic head and neck cancer (HNC). Notable improvements in treatment outcomes have been observed in the recent decades. Modern radiotherapy techniques, such as intensity-modulated radiotherapy and charged particle therapy, have significantly improved tumor target conformity and enabled better preservation of normal structures. However, because of the intricate anatomy of the head and neck region, multiple critical neurological structures such as the brain, brainstem, spinal cord, cranial nerves, nerve plexuses, autonomic pathways, brain vasculature, and neurosensory organs, are variably irradiated during treatment, particularly when tumor targets are in close proximity. Consequently, a diverse spectrum of late neurological sequelae may manifest in HNC survivors. These neurological complications commonly result in irreversible symptoms, impair patients' quality of life, and contribute to a substantial proportion of non-cancer deaths. Although the relationship between radiation dose and toxicity has not been fully elucidated for all complications, appropriate application of dosimetric constraints during radiotherapy planning may reduce their incidence. Vigilant surveillance during the course of survivorship also enables early detection and intervention. This article endeavors to provide a comprehensive review of the various neurological complications of modern radiotherapy for HNC, summarize the current incidence data, discuss methods to minimize their risks during radiotherapy planning, and highlight potential strategies for managing these debilitating toxicities.