Structure Preserved in Radical Neck Dissection
In a radical neck dissection, none of the structures listed in the question are preserved. The radical neck dissection involves removal of all lymph node groups (levels I-V) along with the internal jugular vein, sternocleidomastoid muscle, spinal accessory nerve, and submandibular salivary gland. 1, 2
Understanding Neck Dissection Classifications
Neck dissections are classified into two main categories according to contemporary nomenclature:
Comprehensive Neck Dissection:
- Removes all lymph node groups that would be included in a classic radical neck dissection
- May preserve certain structures (unlike radical neck dissection)
- Typically recommended for N3 disease
Selective Neck Dissection:
- Removes only specific lymph node groups at highest risk for metastases
- Preserves non-lymphatic structures
- Often recommended for N0 disease or low neck tumor burden
Historical Context of Radical Neck Dissection
The radical neck dissection was first described by Crile in the early 20th century and later standardized by Martin 3. This procedure specifically includes removal of:
- All lymph nodes from levels I-V
- Internal jugular vein
- Sternocleidomastoid muscle
- Spinal accessory nerve
- Submandibular salivary gland
The posterior belly of the digastric muscle is also typically removed in a radical neck dissection 4, 5.
Modified Radical Neck Dissection
Due to significant functional and cosmetic morbidity associated with radical neck dissection, modified approaches were developed:
Modified Radical Neck Dissection: Preserves one or more non-lymphatic structures (sternocleidomastoid muscle, internal jugular vein, or spinal accessory nerve) while still removing all lymph node groups 6, 7
Selective Neck Dissection: Removes only specific lymph node groups based on primary tumor location and likely drainage patterns 2
Clinical Implications
The radical neck dissection results in significant functional impairments:
- Shoulder dysfunction due to spinal accessory nerve sacrifice
- Potential venous congestion from internal jugular vein removal
- Cosmetic deformity from sternocleidomastoid muscle removal
- Altered salivary function from submandibular gland removal
These functional implications have led to the decreased use of true radical neck dissection in favor of modified approaches that preserve critical structures while maintaining oncologic efficacy 6.
Common Pitfalls
- Mistaking a modified radical neck dissection for a true radical neck dissection
- Assuming that any comprehensive neck dissection is automatically a radical neck dissection
- Failing to recognize that modern neck dissection approaches are tailored to preserve function while maintaining oncologic principles
The National Comprehensive Cancer Network now recommends using either comprehensive or selective neck dissection approaches based on the extent of nodal disease, with the goal of providing adequate exposure while preserving critical structures when oncologically appropriate 2.