الفهرس 
Anatomy of the Lymphatics of the NeckOnly 14 pages are availabe for public view
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Abstract
Tumor lymph drainage is usually along well recognized lymphatic pathways, but rarer lymph node sites can be involved and may be the only site of the disease, particularly in recurrence.
Facial lymph nodes are one of the unusual sites of lymph node metastases. They comprise four groups including mandibular, buccinators, infraorbital, and malar. The mandibular lymph nodes are also known as supra mandibular facial lymph nodes (SFLNs). These lymph nodes are mobile structures lying within the soft tissues of the cheek between skin and buccinators muscle at the anterior border of the masseter muscle and are closely related to the mandibular branch of the facial nerve and facial vessels. The presence of facial lymph nodes and their significance in the diagnosis and spread of malignant disease has received little attention in the literature. Facial lymph nodes are one of the unusual sites of lymph nodes metastases in head and neck SCC.
There is no consensus whether facial lymph nodes should be included in neck dissection for treatment of head and neck cancer. Facial lymph nodes and their involvement in oral cancer have been discussed in literature since 1971 by Jeffery Robins, but there are no sufficient data in the literature handling these nodes. Adding to the problem, most of the existing studies are based on retrograde studies that do not clarify the exact figures for these nodes.
During neck dissection for head and neck cancer, surgeons did not usually extend their dissection above the inferior border of the mandible where supramandibular facial lymph nodes (SFLN) are, but they keep the inferior border of the mandible as the upper limit of their flaps. Thus, although there are many data on metastases in various neck lymph nodes from head and neck SCC, yet there are few data on SFLNs. In fact, surgeons hesitate in handling the supramandibular facial lymph nodes (SMFLN) because of their close relationship to the marginal mandibular branch of the facial nerve (MM/FN).
The mandibular and cervical branches of the facial nerve arise from the cervicofacial division of the facial nerve. Thus, the lower division of the facial nerve passes lateral to the retromandibular (posterior facial) vein within the substance of the parotid gland in more than 90% of cases; in others it passes medial to the vein. Injury to the mandibular branch of the facial nerve results in a very slight drooping of the angle of the mouth. The drooping is not noticeable when the mouth is in response – only when it is in motion (smiling). Depending on the nature of injury, the drooping may be neuropraxia (temporary), or permanent.
In this prospective study we evaluated the frequency of facial lymph nodes involvement in cases of head and neck cancer and incidence of injury to branches of facial nerve in case of facial lymph nodes dissection.
This prospective study was performed in surgical oncology department, faculty of medicine Menofia University between March 2014 and March 2018 after approval by the hospitals Ethics Committees. It involved 30 neck dissections obtained from 30 patients with head and neck cancers.
Patients included had a primary carcinoma in the head and neck. Patients with locoregional recurrence, distant metastases or with neoadjuvent therapy were excluded from the study.
Resection of the primary tumors of the skin, and oral cavity SCC was performed with 1-2cms safety margins, wide surgical excisions with safety margins, hemiglossectomy, and, or hemimandibulectomy according to the anatomical location of the primary tumor, while total parotidectomy was performed for cases of parotid gland carcinomas. Neck management included modified neck dissection (FND), and, or supraomohyoid neck dissection depending on the primary tumor size, location, clinical presentation, and involvement of cervical lymph nodes.
Out of 30 patients; 22 males (73.3%) and 8 females (26.7%) with a male to female ratio of 2.75:1 were involved. The age of the patients ranged from 39-67 years with a mean of 55.2 + or – 7.6 years. The tumor site was the scalp in 3 cases (10%), lower eyelid in 2 cases (6.7%), lip in 2 cases (6.6%), parotid gland in 6 cases (20%), tongue in 5 cases (16.7%), mucosa of the alveolar margin in 5 cases (16.7%), & buccal mucosa in 7 cases (23.3%).
According to the clinical TNM staging system, the tumor size of the primary sites was T1 in 7 patients (23.3%), T2 in 18 patients (60%), T3 in 3 patients (10%), and T4 in 2 patients (6.7%). For clinical neck lymph node involvement, 16 patients had no clinically palpable neck lymph nodes (N0) (53.3%) at the initial examination; the rest of them (14 patients) had clinically palpable neck lymph nodes (N+) (46.6%). More precisely, 16 patients fell into category N0, 10 patients into category (N1), and 4 patients into category (N2). Regarding the grade of the primary tumor, it was noticed that 55.6% of grade 2 tumors were accompanied with metastatic facial lymph nodes, this percentage declined to 44.4% in grade 3 tumors, and was 0% in grade 1 tumors.