A new paradigm for the diagnosis and management of unknown primary tumors of the head and neck: A role for transoral robotic surgery

Abstract

Objectives/Hypothesis: In 2% to 3% of patients with cancer metastatic to cervical lymph nodes, a primary tumor will not be found despite exhaustive diagnostic efforts. The treatment for these patients includes cervical lymphadenectomy followed by radiation to areas with increased risk of harboring a mucosal primary. Wide-field radiation therapy increases the incidence of xerostomia and dysphagia. Localizing a primary tumor has thus both therapeutic and quality-of-life implications, allowing possible complete surgical excision, concentrated radiation therapy, and potential deintensification of adjuvant therapy. With improved visualization and freedom of motion, transoral robotic surgery (TORS) is an innovative surgical modality that allows resection of oropharyngeal subsites with minimal morbidity.Study Design: Retrospective chart review.Methods: Ten patients with unknown primary tumors of the head and neck were identified. All patients underwent a cervical biopsy, positron-emission tomography/computed tomography, formal endoscopy, and bilateral tonsillectomy. When the initial endoscopy and biopsies did not localize a primary tumor, all patients underwent transoral robotic base of tongue resection.Results: Evaluation of the patients' oropharyngeal mucosa using the robot did not reveal an obvious lesion and no palpable tumors were appreciated in the resected specimens. In 9/10 (90%) patients, pathologic examination revealed invasive squamous cell carcinoma (SCCA) with a mean diameter of 0.9 cm.Conclusions: Unknown primary SCCA presents a diagnostic challenge to the head and neck surgeon. We present a small series of tumors that would have been treated as unknown primaries under traditional diagnostic and therapeutic algorithms. TORS base of tongue resection identified primary tumors in 90% patients with minimal morbidity.

Retrospective analysis of definitive radiotherapy for neck node metastasis from unknown primary tumor: Japanese Radiation Oncology Study Group study

“…Mehta et al reported 10 patients underwent transoral robotic base of tongue CT, computed tomography; MR, magnetic resonance; FDG-PET, 18-fluoro-deoxyglucose positron emission tomography. resection (26). All patients underwent a cervical biopsy, PET/CT, formal endoscopy and bilateral tonsillectomy before this procedure but not identified primary lesion.…”

Impact of the 8th edition of the UICC TNM classification on staging and survival in patients with neck metastases of unknown primary tumor

“…Some recent studies suggest that transoral laser microsurgery (TLM) or transoral robotic surgery (TORS) is more effective for the identification of a primary in the oropharynx especially in the base of tongue (BOT) in patients with suspected CUP [37,38]. Recent case series have reported high rates of detection ranging from 86 to 94% including TLM [38,39] and 72 to 90% including TORS [37,38,40] in the diagnostic work-up of patients with suspected CUP.…”

“…Recent case series have reported high rates of detection ranging from 86 to 94% including TLM [38,39] and 72 to 90% including TORS [37,38,40] in the diagnostic work-up of patients with suspected CUP. According to Durmus et al [41] the PT was identified in 77% of patients (17 of 22) with 80% HPV-positive LNM residing in the palatine tonsil in 59% (13 of 22), and the BOT in 18% (4 of 22).…”

Transoral endoscopic head and neck surgery (eHNS) for minor salivary gland tumors of the oropharynx

“…TORS is currently being used in the management of early-stage tumors, more advanced malignancies, tumor recurrences, deep neck space infections, tumors of unknown primary site, and comparatively benign conditions such as obstructive sleep apnea [1,[15][16][17][18]. The incidence of postoperative complications seen with TORS is generally low and has the potential to be further reduced by increased experience with the technique and an appreciation of risk factors for the most common issues [5,[19][20][21][22].…”