What are the parotid lymph nodes also known as?

Parotid Lymph Nodes: Anatomical and Clinical Significance

The parotid lymph nodes are also known as intraparotid and periparotid lymph nodes, which are located within and around the parotid salivary gland. These nodes represent an important group at risk for metastatic involvement from cutaneous malignancies of the head and neck 1.

Anatomical Distribution

• The largest concentration (47%) of parotid lymph nodes is found in the lower half of the superficial lobe, with 35% concentrated in the inferior part of the cervicofacial branch (lower pole of the parotid gland) 2
• Parotid lymph nodes are distributed in both the superficial and deep lobes of the parotid gland 3
• In anatomical studies, an average of 8.2 lymph nodes have been identified per parotid gland, with approximately 6.5 nodes in the superficial lobe and 1.7 nodes in the deep lobe 3

Clinical Significance

• Parotid lymph nodes are the most commonly involved nodes when skin cancer of the head and neck metastasizes beyond the primary site 4
• These nodes can be involved in both Hodgkin and non-Hodgkin lymphomas, with 80% of all salivary gland lymphomas appearing in the parotid 5
• Lymphomas originating in the parotid can arise from intraparotid or periparotid lymph nodes, or from lymphoid elements associated with other pathological conditions such as sialadenitis, cysts with lymphoid tissue, or autoimmune diseases like Sjögren syndrome 5

Imaging and Diagnostic Considerations

• Imaging studies are essential to determine the extent of tumors and their relationship to the facial nerve when parotid pathology is suspected 6
• CT with IV contrast is commonly used to evaluate palpable parotid region abnormalities, particularly in cases of suspected acute inflammation 7
• MRI with and without IV contrast is preferred for comprehensive evaluation of parotid masses, as it provides detailed information about tumor extent, local invasion, and perineural spread 7
• Preoperative diagnosis of intraparotid lymph nodes by imaging and fine-needle aspiration cytology can be challenging 2

Surgical and Oncological Implications

• The presence of intraparotid lymph nodes has important implications for surgical management of parotid tumors 2
• For malignant tumors in the superficial lobe or lower pole, superficial parotidectomy and lower pole lobectomy should be performed to address potential lymph node involvement 2
• When intraparotid lymph node metastases are detected during surgery, selective neck dissection (at least levels II and III) should be simultaneously performed 2
• Positive intraparotid lymph node metastasis predicts the risk of positive cervical nodal metastasis 2
• In cases of metastatic cutaneous squamous cell carcinoma involving the parotid gland, there is a high incidence of clinical (26%) and occult (35%) neck disease 1
• For metastatic melanoma involving the parotid, clinical neck involvement occurs in 38% of cases, with 27% having occult neck disease 1

Treatment Considerations

• Treatment of the clinically negative neck in patients with metastatic parotid cancer should be considered to reduce the likelihood of failure in cervical nodes 1
• Surgery followed by radiation therapy to doses of at least 60 Gy results in effective local control for patients with parotid area metastasis from cutaneous squamous cell carcinoma 4
• Elective neck irradiation significantly decreases the incidence of subsequent nodal failures and improves neck control in patients with parotid metastases 4
• The deep parotid lymph nodes have significant anatomical and oncological importance, highlighting the necessity of total parotidectomy in cases where intraglandular spread of lymph node metastases is certain or suspected 3