Nodal Metastasis Patterns In Carcinoma of the Temporal Bone

Presentation: P002
Topic: Cancer Biology
Type: Poster
Date:
Session:
Authors: Michael J Ye1; Raghav B Vadhul2; Michael W Sim1
Institution(s): 1Indiana University School of Medicine - Department of Otolaryngology | Head & Neck Surgery; 2Indiana University School of Medicine


Background:

Local treatment involving temporal bone resection followed by postoperative radiation has become standard of care for carcinomas involving the temporal bone. However, the recommended extent of lymph node dissection has yet to be fully defined.


Methods:

Retrospective review was performed including patients undergoing lateral temporal bone resection and neck dissection at Indiana University School of Medicine, a tertiary referral center. Preoperative examination and imaging, surgical notes, and pathological reports were reviewed. Patients were divided into a node positive and node negative group based on evidence of regional metastasis on preoperative clinical and radiological exam, and features between each group were compared.


Results:

36 patients met inclusion criteria.  The average age was 66.0, and 34 patients were male. The predominant pathology was squamous cell carcinoma constituting 21 patients. All patients were advanced T stage, III or IV. Eleven of these patients presented as node positive (N+), and 25 patients presented node negative (N0).  Of 14 patients with positive nodal disease on final pathology, 9 patients had positive parotid nodes alone, 4 had concurrent parotid and lateral neck disease, and 1 had positive lateral neck disease alone. Three out of 25 patients presenting as N0 had positive lymph nodes on final pathology for an occult metastatic rate of 12%. Of these 3, all had positive parotid nodes without lateral neck disease. All pathologically proven lateral neck metastases occurred in the ipsilateral levels 2-4 with the exception of 1 patient with level 5A disease that was identified on preoperative imaging. In patients who did not undergo level 5 neck dissection at initial surgery, there were no regional failures in the neck. In the N+ group, the average primary tumor was more advanced at 5.57 cm compared to 4.03 cm in the N0 group. N+ patients were more likely to have facial weakness (5 of 11) compared to N0 patients (7 of 25) at the initial preoperative appointment.  Postoperatively, 19 patients received adjuvant radiation therapy and 7 underwent chemoradiotherapy. Ten patients received no adjuvant therapy due to favorable pathology and tumor board discussion (4), preoperative radiation (2), death (2), palliation (1), and patient/family wishes (1).


Discussion/Conclusion:

In our data set, the most common locations for nodal metastasis in carcinoma of the temporal bone are the parotid nodes and ipsilateral levels 2-4. It is reasonable to spare level 5 unless there are clinically and radiographically positive nodes in that region. These patients usually require free flap reconstruction and therefore preparing recipient vessels is facilitated by level 2-4 neck dissection. Parotidectomy should be performed due to relatively high rate of metastasis. Further investigation is required to further characterize the recommended extent of elective neck dissection in carcinoma of the temporal bone.