Increased Node Dissection Improved Survival in Node-Negative Oral Cavity SCC

July 21, 2017

Higher nodal yield during definitive surgery for clinically node-negative oral cavity squamous cell carcinoma was associated with improved mortality.

Higher nodal yield during definitive surgery for clinically node-negative oral cavity squamous cell carcinoma (OCSCC) was associated with improved mortality, according to the results of a research letter published in JAMA Otolaryngology – Head & Neck Surgery.

“Because OCSCC is treated primarily by curative surgery, it is imperative to analyze this disease as a separate entity and account for tumor depth of invasion, a crucial prognostic factor,” wrote Chiaojung Jillian Tsai, MD, PhD, of the department of radiation oncology at Memorial Sloan Kettering Cancer Center in New York, and colleagues. “Furthermore, since locoregional recurrent OCSCC patients have poor salvage outcomes, it is appropriate to use a more stringent nodal yield than previously described.”

Although research has linked higher lymph node dissection count with improved survival in patients with head and neck cancer with heterogeneous clinical nodal presentations, the value of extensive neck dissection was still unknown in patients with node-negative disease.

Using data from the National Cancer Database, the researchers identified all patients with node-negative OCSCC diagnosed between 2004 and 2012. All patients had received definitive surgery for their disease. The study looked at association between overall survival and clinical or surgical factors. The primary endpoint was overall survival.

The 7,811 patients included in the study were followed for a median of 48.3 months. Overall survival was 92.2 months. The median node count among patients was 23. More than three-quarters (77%) of patients had no regional lymph node metastasis identified.

Patients with 24 or more dissected nodes were younger and more likely to have advanced clinical or pathologic categories, negative surgical margins, adjuvant therapy, surgery at an academic facility, and private insurance. In addition, patients with more than 24 dissected nodes had significantly longer overall survival compared with patients who had 24 or fewer dissected nodes (hazard ratio, 0.82; 95% CI, 0.75–0.88).

Based on these data, the researchers concluded that “thorough surgical neck evaluation should be advocated for clinically node-negative patients with OCSCC.”

In an editorial that accompanied the research, Jon Mallen St. Clair, MD, PhD, of the department of head and neck surgery at the University of California, San Francisco, wrote, “Defining the threshold of a lymph node dissection that imparts an improved survival rate in oral cavity cancer may represent an important step toward developing a quality metric in the treatment of patients with head and neck cancer. Until recently, no validated quality metrics for patients with head and neck cancer existed, limiting our ability to monitor quality of care.”

The results of this study and other similar research, “suggest that developing clinical best practices and improving guideline adherence may decrease variation in care and improve outcomes, and that developing a standard of care for a quality neck dissection may represent an important part of future clinical guidelines,” he wrote.