E2694. Betel Nut Use in the Pacific Islands - A Risk Factor for Squamous Cell Carcinoma: Imaging Findings on CT
  1. Elianna Goldstein; Tripler Army Medical Center
Betel nut or areca nut is the seed of the Areca catechu palm tree, grown through the Pacific Islands including Guam, Micronesia, and Polynesia among other places. It is highly addictive and most commonly chewed inside a wrap of its leaves or with tobacco. The areca nut is carcinogenic and affects many organs but primarily is a risk factor for cancer of the oral cavity, oropharynx, and esophagus, particularly squamous cell carcinoma (SSC). There is also risk for lung, cervical, and liver cancer. The alkaloids it contains mainly affect the nervous system via both muscarinic and nicotinic receptors, though it affects multiple organ systems in a variety of ways. Betel nut use is a culturally significant practice among Native Hawaiians and Pacific Islanders, might be brought as a gift or shared among family and friends at social gatherings. Cancer rates are notably high in Palau and the Republic of the Marshal Islands. Cancer is the second leading cause of death in US-Affliated Pacific Islands, with one third of their patients dying from their cancer during a 6-year study period. Travel from remote islands and rural areas is limited and patients often must travel by small boat for hours to days to another island for medical care or hospital care. Through the VA Pacific Island Health Care System, our facility sees patients referred by these hospitals, who often present at late stages given the difficulty of getting initial medical care followed by referral to the program. This educational exhibit will show a spectrum of CT findings with pathology correlates from early dysplasia to aggressive squamous cell carcinoma in select patients whose primary risk factor was chewing betel nut. Because many of the islands where betel nut is traditionally used have limited access to medical care, and patients who present at our hospital often have advanced disease, the majority of cases will demonstrate advanced disease.

Educational Goals / Teaching Points
Bring awareness to betel nut chewing as a practice and risk factor for oral squamous cell carcinoma. Demonstrate early and late findings related to betel nut carcinogenesis on CT examination of the neck.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Early findings on contrast-enhanced CT of the neck include the lymph nodes may be asymmetric and primary lesion may be occult or very subtle asymmetry, physical exam is important. Late findings on contrast-enhanced CT of the neck include lymph nodes may be centrally necrotic and asymmetry to frank mass of the oral cavity or oropharynx. Search for complications such as osseous erosion, vascular involvement, or perineural spread.

Betel nut use is a risk factor for oral squamous cell carcinoma. Early CT findings can be subtle and physical exam is important. Late CT findings such as necrotic lymph nodes and locally aggressive tumor with osseous destruction or vascular involvement should trigger a search for clues for perineural invasion on CT, with findings such as osseous remodeling and loss of fat planes along the pathways of the cranial nerves.