Occult metastases predict worse outcomes in oral squamous cell carcinoma
MedWire News: The presence of occult lymph node metastases significantly impacts the overall and disease-free survival of patients with oral squamous cell carcinoma (OSCC).
OSCC is the 10th most common malignancy worldwide and about one-third of these patients are diagnosed while the disease is still local - defined by a lack of clinical or radiologic signs of loco-regional lymph-node metastases (Union for International Cancer Control [UICC] stage 1 or 2).
However, metastases may be present that can only be detected upon dissection of the lymph nodes, and the presence of these occult metastases can have a significant detrimental impact on patients' survival. Thus, there is a question as to whether this subgroup of early OSCC patients should be considered high risk and treated appropriately.
In this retrospective analysis, Oliver Thiele and colleagues (University Hospital, Heidelberg, Germany) assessed whether supraomohyoid neck dissection of level 1, 2a, and upper level 3 is a safe and effective procedure in patients with early OSCC. This procedure has previously been established in the treatment of oral cavity cancer.
In total, 122 patients with localized OSCC who were treated between 2000 and 2009 were analyzed. The mean age of patients was 62.1 years and 66% were male. All patients had their primary tumor removed and then received elective supraomohyoidal neck dissection of level 1 and 2a with or without upper level 3.
The presence of lymph node occult metastases was analyzed according to age, gender, and tumor stage and grade.
Occult lymph node metastases were detected in 13.9% of patients and were found significantly more frequently in patients with T2 compared with T1 tumors (19.7 vs 5.9%).
Patients with occult metastases were found to have significantly worse 5-year overall (62.5 vs 82.2%) and disease-free (17.8 vs 61.9%) survival compared with patients without occult metastases. Regression analysis showed that no other factor had a significant impact on survival.
Writing in the Journal of Cranio-Maxillo-Facial Surgery, the authors write: "Supraomohyoid neck dissection detects occult metastases in early, clinically node-negative OSCC in 13.9% of all cases analyzed. The presence of occult metastases is an independent risk factor, which is associated with a significant reduction of overall and disease-free survival rates."
They conclude: "Patients with early OSCC and occult metastases should be considered as high-risk patients, warranting additional therapeutic approaches."
By Iain Bartlett