What is the prevalence of occult cervical disease and the evidence for using elective neck dissection (END)?
Bottom line: The average rate of occult disease was 22.5%, supporting END in addition to parotidectomy as part of the treatment of P+N0 disease in CSCC of the head and neck.
Background: Patients with metastatic cutaneous squamous cell carcinoma (CSCC) to the parotid gland will commonly be offered parotidectomy and neck dissection in the presence of cervical nodal disease. In the node-negative neck, there is debate about the role of END. Proponents argue that the occult disease rate warrants cervical lymph node removal, but more extensive surgery will inevitably carry greater potential morbidity.
Study design: Literature review.
Setting: Medline and Embase databases.
Synopsis: Mean occult prevalence ranged from 14.7% to 45.2%. From a random effects meta-analysis, the overall prevalence of occult disease was 22.5%. Despite prevalence variability, heterogeneity was low at 27.4%. A fixed effects model gave a similar result with an overall prevalence of 22.0%. Across studies, all primary CSCC locations except for periorbital and posterior scalp sites metastasized to level II. Only one study specifically reviewed occult disease in reference to immunosuppression, finding patients with hematological malignancy, with human immunodeficiency virus, on immunosuppressive medication, or with a history of solid organ transplants had an increased risk of occult nodal disease. The range of locoregional recurrence in the neck, when described independently, was between 0% and 12.4%. Five-year disease-specific survival was variably reported from 58% to 83%, and five-year overall survival ranged from 48% to 80%. Surgery with or without radiotherapy resulted in better survival than radiotherapy alone, and immunosuppressed patients had worse outcomes. No paper described complication rates comparing parotidectomy alone to parotidectomy with END, or detailed any data regarding quality-of-life outcomes in patients undergoing END.
Citation: Rotman A, Kerr SJ, Giddings CEB. Elective neck dissection in metastatic cutaneous squamous cell carcinoma to the parotid gland: a systematic review and meta-analysis. Head Neck. 2019;41:1131–1139