Transoral robotic surgery (TORS) has increased in popularity in a variety of different indications. In 2006, O’Malley et al. began the introduction and application of the Intuitive Surgical da Vinci robot to head and neck surgery [
A 58-year-old Caucasian male presented with painless solitary left-sided upper neck mass of 2-month duration. He reports smoking one pack per day for 30 years but denies alcohol or drug abuse. After comprehensive physical examination, which was unremarkable, fine needle aspiration (FNA) confirmed squamous cell carcinoma (SCC). A PET-CT scan showed single FDG avid 3.5 cm left cervical LN at level II.
The patient was presented at our institutional head and neck tumor conference and the consensus was to proceed with multiple targeted biopsies from the base of tongue (BOT) and bilateral tonsillectomy all of which were negative for malignancy. The patient was offered RT as a definitive management for metastasis of unknown primary (MUP) clinical stage T0N2aM0, stage IVA, but he opted to left ND. Pathology revealed one positive LN for SCC, at level II, out of fifty six LNs. It measured 4.5 cm in the greatest dimension with no extracapsular extension. The pathologic staging was MUP stage IVA (pT0pN2aM0).
PET-CT scan, 6 months later, showed interval development of an intense hypermetabolic focus in the region of the left BOT and right level II LN. He underwent incisional biopsy of the left BOT mass, which was positive for SCC and HPV/p16. The patient was offered RT which he declined and opted to TORS and right ND, which revealed SCC of the left BOT, tumor measured 1.7 cm (pT1) with negative margins, and all the 29 LN were negative (pN0). He was pathologically staged as BOT, pT1pN0 M0, stage I. It is not clear whether the patient developed a second primary in the form of squamous cell carcinoma of the BOT or the primary of the initial undiagnosed MUP has emerged. Subsequently, he was offered adjuvant RT but he persistently declined. The patient did very well until a follow-up PET-CT scan (18 months later) showed a solitary 1.5 × 1.3 × 2.5 cm (Figure
The solitary left lateral retropharyngeal lymph node involvement.
The patient was represented at our institutional multidisciplinary head and neck tumor conference and the consensus was to proceed with salvage concurrent chemo-RT. The patient underwent CT simulation and IMRT based treatment. Two PTVs with dose painting were designed. The high dose region included the grossly enlarged FDG avid left RPN which received 70 Gy in 33 fractions. The lower dose for elective regions included the contralateral RPN, BOT, lymphatic in transit, and bilateral neck; all received 54 Gy in 33 fractions (Figures
The isodose curves of RT treatment plan: axial, sagittal, and coronal views of PTVs 70 and 54 Gy.
TORS represents a shift from the conventional treatment paradigm on multiple levels. It does not require a mandibulotomy, mandibular swing, or tracheotomy for airway protection. Avoiding these surgical maneuvers provides patients with a far less morbid procedure [
The primary drainage of the oropharynx is to the neck nodes (mainly level II) and to the lateral RPN. RPN are located in the retropharyngeal and parapharyngeal space that is closely related to cranial nerves IX through XII, the internal jugular vein, and the internal carotid artery at the base of skull which make them inaccessible surgically. Metastases to the RPN are most commonly associated with cancers of the nasopharynx, oropharynx, and pharyngeal wall. Notably, these metastases occur primarily along the lateral RPN chains. Involvement of the medial chain is extremely rare [
The dismal clinical impact of RPN metastases has been reported in the literature. McLaughlin et al. reported on 774 patients with SCCHN. They found that the number of cervical nodal groups involved was the most significant factor (
RT is used as adjuvant therapy, ±chemotherapy as dictated by the surgical pathology. Due to the rarity of reports that addressed the RPN involvement after TORS, there is no universal consensus on the management of this situation but traditionally salvage RT ± chemotherapy would be recommended. To the best of our knowledge there is no data to support the routine use of adjuvant RT after TORS especially with favorable pathological findings. However, due to the odds of RPN involvement in the context of oropharyngeal tumors, we believe that post-TORS adjuvant RT would be wise, as it comprehensively covers all areas at risk. In cases with adverse prognostic features (positive margins and extra capsular extension) concurrent chemo-RT should be offered [
In the current report, salvage chemo-RT may offer a successful regional control for the RPN with acceptable toxicities. This case report is particularly important because it is unlikely that a prospective trial will be performed in this patient population. As there is little in the literature to guide treatment, we treated this patient in a similar fashion to salvage treatment strategy to SCCHN with complete success thus far despite the short followup. The real risks of local, regional nodal relapse or metastatic potential after TORS are unknown. Therefore, the appropriate areas to receive higher or lower doses, including nodal levels, are unclear.
Another issue that must be considered in an era of depleting health resources is the costeffectiveness of the interventions. Investigators have reported that the costs of multimodality approach (i.e., TORS, ND, RT ± chemotherapy) were 10 times the cost of treatment with chemo-RT alone for operable tumors of the oropharynx. The majority of cost was related to inpatient and outpatient care, rather than surgical procedure [
TORS followed by adjuvant RT seems reasonable in the context of BOT of the head and neck due to the odds of lateral RPN involvement. Further reports are warranted to optimize post-TORS adjuvant treatment.
All the authors do not have any conflict of interests.
There is no copyrighted information. The report was approved by the authors’ institutional review board.