Neck masses can be categorized based on the time of their occurrence into congenital neck masses and acquired neck masses. Acquired neck masses can be further divided into inflammatory masses, tumor-related masses, immune-related masses, and hematomas or fluid accumulations resulting from trauma or postoperative changes. Inflammatory masses can be divided into specific inflammatory masses (e.g., tuberculous) and nonspecific inflammatory masses. Tumor-related masses can be classified as benign or malignant, with malignant tumors further subdivided into primary and metastatic types. Congenital and inflammatory neck masses are addressed in relevant sections, while tumor-related neck masses are the main focus of this section.
Diagnosis
Medical History
The patient's age and gender are important considerations. Congenital conditions and vascular tumors are more common in children, whereas malignant tumors are more prevalent in elderly patients, especially older males. Attention should also be given to the duration of the condition. Long-standing neck masses persisting for several years (excluding thyroid nodules with or without cervical lymph node metastases) are generally considered benign or congenital. Rapid enlargement of neck masses within 1–2 weeks is often inflammatory in nature, with a low likelihood of malignancy. The vast majority of metastatic cancers in the neck have a shorter disease course, progressively enlarging over the course of several months. Consequently, the duration of the condition is an important diagnostic clue: conditions lasting several days are mostly inflammatory, those lasting several months are more likely malignant, and those persisting for years are often benign or congenital in nature.
Physical Examination
The physical examination should assess characteristics such as the position, size, hardness, mobility, skin color, adhesion, tenderness, and pulsation of the neck mass. Cystic and soft masses are often benign, such as thyroglossal duct cysts, branchial cleft cysts, dermoid cysts, or lipomas. Schwannomas and neurofibromas tend to be harder with limited mobility, showing greater lateral than vertical movement, and may be accompanied by radiating sharp or numb sensations along the course of the nerve. Malignant tumors are generally firmer, with limited mobility in advanced stages, and metastatic tumors may present as multiple masses with minimal tenderness. Carotid body tumors may exhibit pulsation or an audible vascular bruit upon auscultation.
Imaging Techniques
Various imaging modalities, including ultrasound, CT, MRI, and PET-CT, are utilized, each with its distinctive advantages that can complement one another. Ultrasound is cost-effective and non-invasive, and ultrasound-guided biopsy can be performed when necessary. However, its sensitivity and specificity are more subject to operator dependency. CT and MRI offer non-invasive, relatively cost-effective, and detailed multi-planar visualization. CT scans without contrast are somewhat limited in showing variations in tumor density and the relationship with adjacent structures, often requiring contrast-enhanced CT for further evaluation. MRI is superior in depicting the relationship between the tumor and surrounding tissues but is prone to motion artifacts. PET-CT is advantageous in differentiating between benign and malignant tumors and identifying primary sites in cases of cervical lymph node metastasis with unknown origin, though its cost is relatively high.
Fine Needle Aspiration Cytology and Core Needle Biopsy
Ultrasound-guided fine needle aspiration cytology (FNAC) or core needle biopsy has a high diagnostic accuracy, is simple to perform, safe, and minimally invasive. These procedures do not negatively impact subsequent treatments and are valuable in determining the nature of the tumor.
Excisional or Incisional Biopsy of the Neck Mass
For cases where FNAC or core needle biopsy yields inconclusive results and malignancy is suspected, surgical biopsy of the mass may be performed. However, excisional or incisional biopsy of cervical lymph nodes in patients with metastatic cancer of the head and neck may adversely affect subsequent treatment. Therefore, examination and biopsy of the primary lesion should be prioritized. If the primary lesion cannot be identified after careful evaluation, cervical biopsy may be considered as a last resort.
Differential Diagnosis
Congenital Neck Masses
Common congenital neck masses include thyroglossal duct cysts, branchial cleft cysts and fistulas, and vascular tumors such as hemangiomas or lymphangiomas.
Benign Neck Tumors
Common benign neck tumors include schwannomas, neurofibromas, lipomas, and carotid body tumors.
Malignant Neck Tumors
Primary malignant tumors of the neck most commonly include lymphomas, with rare cases of neurogenic malignant tumors and soft tissue sarcomas. Metastatic cervical lymph node cancers are most frequently derived from head and neck tumors, with fewer originating from thoracic, abdominal, and pelvic regions. A small number may have an unknown primary origin.
Treatment Principles
Congenital Neck Masses
Thyroglossal Duct Cyst
Complete surgical excision is the most effective treatment. The root of the thyroglossal duct cyst is located beneath or behind the hyoid bone. Therefore, surgery involves not only the complete removal of the cyst and its associated duct extending toward the base of the tongue but also resection of the central portion of the hyoid bone to reduce the risk of recurrence.
Branchial Cleft Cysts and Fistulas
The cyst and fistula are surgically excised in their entirety. In cases with concurrent infection, infection control is required before elective surgery. Since the cysts and ducts are adjacent to critical anatomical structures, including the common carotid artery, internal carotid artery, external carotid artery, internal jugular vein, vagus nerve, and superior laryngeal nerve, repeated infections can cause adhesions to these structures, complicating surgical dissection. Care is needed to avoid injury to vital vessels and nerves during surgery. For branchial cleft fistulas with a clearly identified internal opening in the piriform recess, endoscopic cauterization and suturing of the internal fistula's opening under a suspension laryngoscope is an alternative treatment option.
Hemangiomas
Common types include capillary hemangiomas, cavernous hemangiomas, and mixed capillary-cavernous hemangiomas. Treatment methods include cryotherapy, sclerotherapy, injection of chemical agents, laser therapy, radiation therapy, or surgical excision.
Benign Neck Tumors
Schwannoma
Schwannomas can arise from nerves such as the glossopharyngeal nerve, vagus nerve, accessory nerve, phrenic nerve, cervical sympathetic trunk, cervical plexus, and brachial plexus. They most frequently involve the vagus nerve, cervical sympathetic trunk, and glossopharyngeal nerve. Typically presenting as solitary, slow-growing masses with a complete capsule, malignant transformation is rare. Schwannomas are usually located in the carotid triangle or parapharyngeal space. Surgical excision is the only effective treatment and can be approached either externally through the neck or intraorally. The external cervical approach is more commonly used, offering better surgical exposure for complete removal while allowing preservation of surrounding structures such as nerves and vessels. However, for neurogenic tumors, even with intracapsular enucleation, nerve continuity is difficult to preserve, and nerve damage is common. For tumors protruding prominently into the pharyngeal cavity, surgery may use the intraoral approach if the lesion is small, has good mobility, and the main vessels lie outside the mass.
Neurofibroma
Neurofibromas originate within the nerve sheath and may involve sensory, motor, or sympathetic nerves. They often present as slow-growing solitary masses without a distinct capsule and may undergo malignant transformation. Clinical presentation and diagnosis are similar to those of schwannomas. Treatment involves surgical excision, but nerve continuity cannot typically be preserved, and postoperative nerve dysfunction may occur.
Lipoma
Lipomas may appear as solitary, multiple, or diffuse growths. They generally grow slowly, often asymptomatic, and are discovered incidentally or during medical examinations. Surgical excision is the primary treatment, with a good prognosis.
Carotid Body Tumor
Treatment primarily involves surgical intervention. Detailed information on treatment strategies is covered in Section 1, Chapter 5, Part 7.
Malignant Neck Tumors
Primary Malignant Tumors
Lymphomas are most common in young and middle-aged males. Lymphatic tissues throughout the body can be affected, with cervical, axillary, inguinal, mediastinal, and abdominal lymph nodes being the most frequently involved, often presenting as superficial lymphadenopathy. Based on pathological features, lymphomas are classified into Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL), with chemotherapy as the primary treatment.
Neurogenic malignant tumors in the neck are rare and mainly include malignant peripheral nerve sheath tumors (neurofibrosarcomas) or malignant transformation of neurofibromas. These tumors typically show rapid growth with invasive extension to surrounding tissues. Treatment involves wide surgical excision, followed by radiotherapy or chemotherapy, particularly in cases with distant metastases. The prognosis is generally poor.
Cervical Lymph Node Metastases
Treatment focuses primarily on addressing the primary lesion. Management of cervical metastatic lesions varies depending on the primary tumor. Nasopharyngeal carcinoma metastases are often managed with radiotherapy or combined therapy. Metastases from nasal and paranasal sinus cancer, laryngeal cancer, hypopharyngeal cancer, and thyroid cancer are typically treated with surgery or surgery-based comprehensive therapy, incorporating radical or modified radical neck dissection based on the extent of the metastases. For metastatic squamous cell carcinoma of the neck with an unknown primary, lymphadenectomy is performed, followed by local radiotherapy or chemoradiotherapy. In advanced tumor stages, when surgery is not feasible or patients cannot tolerate it due to poor overall condition, comprehensive treatments involving radiotherapy, chemotherapy, targeted therapy, or immunotherapy are considered.