Indications and outcomes for elective dissection of level V in primary parotid cancer

Abstract

Background The extent of cervical lymphadenectomy required for primary parotid cancer is not well‐established. Methods In this retrospective case–control study, 84 patients who underwent primary parotidectomy and neck dissection for primary parotid cancer between 2010 and 2019 were identified and analyzed. Results Of the 84 patients, 37 underwent elective level V neck dissection. All six (16.0%) who had occult level V nodes had clinically evident, preoperative anterior cervical metastases, a statistically significant finding. No other clinical factors are correlated with posterior neck involvement. There was no significant difference in disease‐free or overall survival for patients with occult level V disease relative to positive lymph nodes in other levels. Conclusions Patients with clinically evident anterolateral cervical lymphatic metastases from parotid cancer preoperatively have high rates of occult level V nodes. Level V neck dissection can be avoided in cN0 patients and offered no survival advantage.

Do Lymph Node Ratio and Histopathologic Parameters Have Any Prognostic Value in Primary Parotid Gland Carcinomas?

“…High-grade tumor histology after parotidectomy without neck dissection in cN0 neck may require a second operation for neck dissection. The occult metastasis rates of PG cancers are 4.3% in T1 or T2 tumors, 35% in T3 or T4 tumors, 6.1% in low or intermediate-grade tumors, and 24.2% in high-grade tumors in cN0 patients ( 20 ). Also, occult nodal disease occurs in 13.6% of cN0 patients ( 20 ).…”

The evolving landscape of salivary gland tumors

“…However, this was a single‐institution, retrospective study, and it is unclear whether these patients could have been adequately treated with adjuvant radiotherapy. It is notable that no regional recurrences were seen in patients who did not undergo level V dissection 42 …”

“…However, others have advocated for a comprehensive (levels I–V) neck dissection 41,43 . One study demonstrated that 60% of patients undergoing neck dissection with clinically evident anterolateral neck disease also had occult nodal metastases in level V 42 . However, this was a single‐institution, retrospective study, and it is unclear whether these patients could have been adequately treated with adjuvant radiotherapy.…”

“…Some authors have argued that dissection of level I has already been partially completed after parotidectomy and adds little additional morbidity; similarly, dissection of level IV is not much more extensive once levels II and III have been dissected 37 . Occult metastases in level V are very unlikely in the absence of clinically evident nodes elsewhere, 42 and a level V dissection may result in significant morbidity, which often results from stretch injury to the spinal accessory nerve. As such, some surgeons prefer to avoid this by limiting their level V dissection to removal of level Vb just behind the sternocleidomastoid muscle.…”

“…It is notable that no regional recurrences were seen in patients who did not undergo level V dissection. 42…”