Bone Marrow Invasion and Mylohyoid Muscle Invasion May Indicate Cervical Lymph Node Metastasis from Oral Squamous Cell Carcinoma of the Posterior Mandibular Alveolar Ridge

STATEMENT OF THE PROBLEM

Metastasis to the cervical lymph node is a critical event in progression of oral squamous cell carcinoma. Identification of lymph node metastasis is crucial in treatment planning. Unfortunately, currently available diagnostic methods suffer probability of omitting the identification of occult lymph node metastasis. This study is aimed to detect magnetic resonance imaging predictive factors for lymph node metastasis in patients suffering oral squamous cell carcinoma of the posterior mandibular alveolar ridge.

MATERIALS AND METHODS

 A retrospective case-control study was performed. From a population of 26 patients with previously untreated oral squamous cell carcinoma of the posterior alveolar ridge, patients with lymph node metastases were compared to those patients without lymph node metastasis. Preoperative magnetic resonance images were assessed in terms of greatest dimension of tumor, bone marrow invasion, sublingual space invasion, masticator space invasion, buccinator muscle invasion, and mylohyoid muscle invasion.

METHODS OF DATA ANALYSIS

 Fisher’s exact test was performed to verify the relations of the factors assessed and the presence of cervical lymph node metastasis. Factors assessed to be related to lymph node metastasis were re-assessed to verify their effect on overall survival by means of the product-limit method. PASW Statistics 17.0 was used for statistical calculations.

RESULTS

 Bone marrow invasion and mylohyoid muscle invasion were associated with cervical lymph node metastasis using 0.05 level of test. Our data reconfirmed that lymph node metastasis affects overall survival with a p-value of 0.003. We failed to reject the hypotheses that bone marrow invasion and mylohyoid muscle invasion affect overall survival.

CONCLUSIONS

 Based on our results, we suggest that bone marrow invasion and mylohyoid muscle invasion have diagnostic value for lymph node metastasis from oral squamous cell carcinoma of the posterior mandibular alveolar ridge.

REFERENCES

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