We read the paper by Katan et al with great interest. We congratulate the authors for presenting audacious and statistically significant evidence in support of selective neck dissection (SND) as opposed to modified radical neck dissection (MRND) in node-positive (N+) necks.
Based on our expertise and previous publications, ,, we would like to offer two additional suggestions:
Surgical technique
In our practice, we utilise loupe magnification, a harmonic scalpel, monopolar diathermy, and a 0° endoscope to facilitate small-incision neck dissection for lymphadenectomy of levels I–V.
In our series, the incidence of spinal accessory nerve injury was 1.7% (1 of 56 patients). We observed one patient with transient weakness of the marginal mandibular branch. The aesthetic outcomes were excellent. We had eight patients (14%) with regional neck recurrences in N+ necks, equivalent to what the authors observed in their data. In our series five of eight patients had recurrence of the contralateral neck, and only one, who had level I-III for a left maxillary tumour, had recurrence at level IV.
We believe that adopting this technique can facilitate lymphadenectomy with minimal morbidity.
Consideration of levels IV and V in selected cases
Over the years the classifications for neck dissections have been revised. SND involves removal of some of the cervical lymph nodes. In the past we referred to SND as subtypes:
-
•
supraomohyoid: levels I-III
-
•
extended supraomohyoid (anterolateral): levels I-IV
-
•
posterolateral: levels II-V, suboccipital, postauricular
-
•
lateral (jugular): levels II-IV
-
•
anterior (central): level VI
However, this has been altered, with parentheses specifying which levels have been removed, for example, SND I-III.
MRND involves the removal of cervical nodes, levels I through V with preservation of one or more of the key extra nodal structures ( spinal accessory nerve , sternocleidomastoid muscle , and internal jugular vein ).
Although uncommon, metastases to lower level IV and V nodes have been reported, with an incidence of approximately 27% and 6%, respectively. In selected cases, clearance of levels I–IV or I–V may provide both surgical and oncological benefits.
We agree with the authors that SND including levels 1-IV and even levels I-V in the N+ neck will achieve sufficient control and this will be further strengthened with adjuvant therapy.
The main concern in addressing levels IV and V is the increased surgical difficulty and the potential risk of motor nerve injury. However, following our described approach to lymphadenectomy, we believe that the inclusion of levels IV and V in selected minimal cases can be performed with good aesthetic results, preserved neck contour, and very low motor nerve morbidity.
