Head and Neck Cancer-related Pain: A Descriptive Analysis of the Pain Phenotypes

Abstract Title:

Head and Neck Cancer-related Pain: A Descriptive Analysis of the Pain Phenotypes

Background: Head and neck cancers (HNCs) represent a heterogenous group of aerodigestive tract cancers, among which 90% are squamous cell carcinoma or variants thereof. The prevalence of pain in all cancer types is around 50%. However, this is reported to be higher, averaging 70% among HNCs ¹. Prior studies have suggested that up to 80% of all patients with cancer-related pain receive inadequate pain management ². A possible reason for this inefficacy is the diverse clinical signs and symptoms of HNC-related pain. The understanding of this variable clinical presentation is limited across the literature, and to date, no such data exists.


Purpose/Objectives: This study aimed to describe the clinical characteristics and prevalence of different painful phenotypes among patients with HNC-related pain based on modifications of the phenotypes described in the International Classification of Orofacial Pain (ICOP-1) and International Classification for Headache Disorders (ICHD-3) ^{3, 4}.


Method:
A prospective study was conducted on 100 patients who presented with HNC-related pain. Inclusion criteria included all adult male and female patients who presented with HNC-related pain who consented to participate in the study. The diagnosis of HNC-related pain was modifying the diagnostic criteria for headache attributed to intracranial neoplasm, described in ICHD-3 ³. HNC in this study was defined as primary tumors originating from the head and neck region or tumors derived from a different site in the body and then metastasized to the head and neck area, as diagnosed by a board-certified oncologist and in accordance with the American Joint Committee on Cancer (AJCC) Guidelines ⁵. Participants with oropharyngeal mucositis, and post-operative were excluded.



Results: Among the participants included, 68% were male, and the mean age of the cohort was 49.71±14.14 years. The most common cancer type was squamous cell carcinoma(81%). All participants had advanced disease. The most prevalent primary disease sites were the tongue(29%) and buccal mucosa(24%). The average pain intensity in last month was 5.88±2.53 and the worst pain severity was 8.95±1.53. In most participants, the pain was unilateral in distribution and constant in periodicity. The most common descriptors of pain were dullache, burning, and sharp. The most common clinical pain phenotype were myofascial pain disorder, jawbone pain disorder, and burning pain disorder.
 


Conclusions: These findings suggest that HNC-related pain has a varying and complex clinical profile. Signs and symptoms may mirror the pain profiles of primary pain disorders, such as myofascial pain, jaw bone pain, or burning pain disorders, and often present together as a cluster of phenotypes. The presence of each or multiple clinical phenotypes in a patient with HNC-related pain is clinically relevant, as each phenotype has its own underlying pathophysiology and evidence-based treatment. Future studies using the clinical phenotype model for tailoring the management of HNC-related pain patients are advocated. Furthermore, the inclusion of HNC-related pain as a diagnostic category in the upcoming versions of head and neck pain classification systems is recommended.

References: 1. Epstein, J. B., Elad, S., Eliav, E., Jurevic, R., & Benoliel, R. (2007). Orofacial Pain in Cancer: Part II—Clinical Perspectives and Management. Journal of Dental Research, 86(6), 506–518. https://doi.org/10.1177/154405910708600605

2. Yarom, N., Sroussi, H., & Elad, S. (2019). Orofacial Pain in Patients with Cancer and Mucosal Diseases. In C. S. Farah, R. Balasubramaniam, & M. J. McCullough (Eds.), Contemporary Oral Medicine (pp. 2187–2212). Springer International Publishing. https://doi.org/10.1007/978-3-319-72303-7_39

3. Headache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders, 3rd edition. (2018). Cephalalgia: An International Journal of Headache, 38(1), 1–211. https://doi.org/10.1177/0333102417738202

4. International Classification of Orofacial Pain, 1st edition (ICOP). (2020). Cephalalgia, 40(2), 129–221. https://doi.org/10.1177/0333102419893823

5. Edge, S. B., & Compton, C. C. (2010). The American Joint Committee on Cancer: The 7th edition of the AJCC cancer staging manual and the future of TNM. Annals of Surgical Oncology, 17(6), 1471–1474. https://doi.org/10.1245/s10434-010-0985-4