Cutaneous squamous cell carcinoma of the head and neck metastasizing to the parotid gland—A review of current recommendations

Abstract

Cutaneous squamous cell carcinoma (SCC) of the head and neck may metastasize in up to 5% of patients, with the parotid lymph nodes the most frequent site for spread. Metastases frequently show delayed presentation after the primary cancer had been treated. The optimum treatment should be surgery followed by adjuvant radiotherapy, with an appropriate parotidectomy, and preservation of the facial nerve if not involved by tumor and treatment to the neck. In a clinically N0 neck, levels I to III should be cleared for facial primaries, levels II to III for anterior scalp and external ear primaries, and levels II to V for posterior scalp primaries. Approximate 5-year disease-specific survival (DSS) after treatment was 70% to 75%. Patients with immunosuppression, in particular transplant recipients, are at high risk of developing aggressive metastatic cutaneous SCC. Modifications of the staging systems have demonstrated the prognostic benefits of accurately staging parotid and/or neck nodal disease.

Advanced Squamous Cell Carcinoma of the Skin

“…When parotid metastasis with clinical negative neck are present, the risk of occult metastases in the cervical lymph nodes reaches 35-50%, which justifies elective neck dissection in the presence of parotid involvement (O'Hara, Ferlito et al 2010). The data by Vauterin revealed when positive pathological neck is observed, level II is involved in 79% of cases and external jugular chain lymph nodes are particularly at risk, what should have not be forgot to be included in the neck dissection.…”

“…The use of sentinel lymph node in squamous cell carcinoma in head and neck is not yet defined and is not routinely used in cancer not melanoma, due to the low risk of nodal metastasis, but has potential for improved survival in patients at high risk (O'Hara, Ferlito et al 2010). The sentinel lymph node study in the parotid region should be done with caution because it adds a possible morbidity due to the risk of facial nerve injury.…”

“…This classification was pointed by several authors as insufficient, what have already indicated the need of a new proposal for lymph nodes staging, including a P stage for parotid metastasis and stratification of nodal disease (O'Brien, McNeil et al 2002;Ch'ng, Maitra et al 2006). The seventh edition of AJCC incorporated some changes in nodal classification aligning with the staging of lymph nodes from others sites of head and neck but the P staging has not been implemented, because of the benefit of having subgroups of P and N stage is uncertain, but further research may demonstrate the need of this staging system (Palme, MacKay et al 2007;Forest, Clark et al 2010;O'Hara, Ferlito et al 2010) In a survey of tertiary treatment centers, about 5% of squamous cell carcinomas present skin present metastasis, usually to regional lymph nodes of the parotid and cervical level II. (2, 5).…”

“…Levels IV and V are only involved in massive lymph node disease to the neck, except in situations where the primary is located in the posterior scalp, in which the involvement of this code chain can be isolated. Metastases to the level I is present alone when the primary occurs in the anterior region of the face (O'Hara, Ferlito et al 2010). …”

“…The radiological search of metastases to the parotid and neck should be performed only in patients at high risk, which can use CT, MRI and USG-guided FNA (O'Hara, Ferlito et al 2010). …”