Basaloid Squamous Cell Carcinoma Not Predictive of Worse Outcome vs Squamous Cell Carcinoma in Head and Neck Cancer
In a study reported in JAMA Otolaryngology-Head & Neck Surgery, Okechukwu R. Linton, MD, MBA, of Indiana University School of Medicine, and colleagues assessed the prognostic significance of head and neck basaloid squamous cell carcinoma, which is considered a more aggressive form of squamous cell carcinoma. They found that basaloid squamous cell carcinoma is not associated with poorer outcome compared with squamous cell carcinoma.
Study Details
The study involved retrospective review of the Surveillance, Epidemiology, and End Results database including individual case data for 34,196 patients treated between January 2004 and December 2009 who had head and neck primary squamous cell carcinoma (n = 33,554) or basaloid squamous cell carcinoma (n = 642) of the oral cavity, oropharynx, or larynx/hypopharynx. Patients had received treatment with surgery or radiation. Patients with metastatic disease were excluded.
For the 76 basaloid squamous cell carcinoma vs 12,417 squamous cell carcinoma patients with oral cavity disease, basaloid squamous cell carcinoma patients were significantly more likely to be female, to be black, to have higher tumor grade, and to have higher group stage.
For the 486 basaloid squamous cell carcinoma vs 13,422 squamous cell carcinoma patients with oropharynx disease, basaloid squamous cell carcinoma patients were significantly more likely to have higher tumor grade, smaller median tumor size, and lower tumor T stage.
For the 80 basaloid squamous cell carcinoma vs 7,715 squamous cell carcinoma patients with larynx/hypopharynx disease, basaloid squamous cell carcinoma patients were significantly more likely to have higher tumor grade, higher group stage, lower tumor T stage, and higher N stage, to have received radiation or surgery alone (compared with surgery plus postoperative radiation therapy), and to not have disease as a first primary.
Oral Cavity
For oral cavity disease, univariate analysis showed that age, race, tumor grade, group stage, TNM stage, tumor size, treatment type, lymph node dissection, and prior cancer diagnosis were significant predictors of overall survival. There was no significant difference in 3-year overall survival between basaloid squamous cell carcinoma and squamous cell carcinoma patients (53.9% vs 62.3%, P = .28). On multivariate analysis, all variables retained a significant association except M status and prior cancer diagnosis.
Oropharynx
For oropharynx disease, race, age, tumor histology, tumor grade, group stage, TNM stage, tumor size, treatment type, lymph node dissection, and prior cancer diagnosis were significant predictors of overall survival on univariate analysis, with 3-year overall survival being significantly greater among basaloid squamous cell carcinoma patients (79.8% vs 65.1%, P < .001). On multivariate analysis, all variables retained significance except for sex, type of therapy, and prior cancer diagnosis, with the hazard ratio (HR) for death for basaloid squamous cell carcinoma vs squamous cell carcinoma being 0.73 (P = .03).
Larynx/Hypopharynx
For larynx/hypopharynx disease, sex, age, tumor histology, tumor grade, group stage, T stage, N stage, tumor size, treatment type, lymph node dissection, and prior cancer diagnosis were significant predictors of overall survival on univariate analysis, with 3-year overall survival being significantly greater in squamous cell carcinoma patients (67.0% vs 58.1%, P = .03). On multivariate analysis, all variables retained significance except sex, tumor histology, tumor grade, treatment, and prior cancer diagnosis, with the difference in overall survival between basaloid squamous cell carcinoma and squamous cell carcinoma patients no longer being significant (HR = 0.93, P = .80)
The investigators concluded, “Compared with [squamous cell carcinoma], [basaloid squamous cell carcinoma] is not an independent adverse prognostic factor for patients with head and neck cancer. The Surveillance, Epidemiology, and End Results analysis has limits, including lack of information regarding chemotherapy, but after controlling for disease and treatment variables, including neck dissection and radiotherapy, basaloid squamous cell carcinoma histology did not have an independent adverse prognostic effect on overall survival.”
The investigators noted that the reported association between human papillomavirus and basaloid squamous cell carcinoma histology may explain the reduced risk for death in patients with oropharynx basaloid squamous cell carcinoma vs squamous cell carcinoma.
The study was supported in part by the Jesse N. Jones III Memorial Fund for Head and Neck Cancer Research at the Indiana University Melvin and Bren Simon Cancer Center.
Mark W. McDonald, MD, of Indiana University Health Proton Therapy Center, is the corresponding author for the JAMA Otolaryngology-Head & Neck Surgery article.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
