Utility of Panendoscopy for the Detection of Unknown Primary Head and Neck Cancer in Patients with a Negative PET/CT Scan

Abstract

We conducted a retrospective review of the records of 23 patients who had been diagnosed with regionally metastatic head and neck squamous cell carcinoma from an unknown primary tumor. Our goal was to assess the utility of panendoscopy in locating the primary tumor in those patients whose positron-emission tomography/computed tomography (PET/CT) fi ndings were negative. Overall, we found that PET/CT had correctly identifi ed the unknown primary in 12 of the 23 patients (52%); panendoscopy confi rmed this fi nding in all 12. Of the remaining 11 patients, however, panendoscopy located the primary tumor in only 1 (9%). In this era of cost containment and ongoing advances in imaging and transnasal esophagoscopy, it is important to revisit the workup of an unknown primary in patients with a negative PET/CT scan. Th ere are various advantages and disadvantages to performing panendoscopy with biopsy in patients with an unknown primary and a negative PET/CT scan, but our results and the fi ndings of others indicate that it will detect the primary in only about 10% of these cases. We recommend careful selection of patients who are to undergo panendoscopy for the routine workup of an unknown primary.

Transoral robotic approach to carcinoma of unknown primary

“…Despite the availability of several different diagnostic modalities, there is no 100% sensitive instrument for primary tumor site identification . Panendoscopy of the upper esophagus, trachea, bronchi, laryngopharynx, and nasopharynx with the patient under general anesthesia and directed biopsies of the clinically and radiologically suspected sites is often the diagnostic surgical method . However, the primary tumor site identification rate of this technique alone is only 17% to 40% .…”

“…Panendoscopy of the upper esophagus, trachea, bronchi, laryngopharynx, and nasopharynx with the patient under general anesthesia and directed biopsies of the clinically and radiologically suspected sites is often the diagnostic surgical method . However, the primary tumor site identification rate of this technique alone is only 17% to 40% . Preoperative PET/CT scan has a higher tumor site identification rate (44.2%) when compared to other radiological strategies; however, it has a false‐positive rate of 28%.…”

“…Treatment planning based on a PET/CT without pathologic confirmation is not recommended, because treatment could be directed toward a false‐positive site, rather than the entire upper aerodigestive tract. This in turn causes undertreatment of the actual primary disease site . The highest rate of sensitivity among these approaches is achieved with the combination of PET/CT, panendoscopy, and directed biopsies, which is still reported to be no more than 59.6%.…”

“…In spite of these seemingly comprehensive diagnostic tools, the primary tumor location in more than 40% of these cases remains unknown . As a result, patients with true carcinoma of unknown primary (CUP) undergo extensive head and neck irradiation and chemotherapy …”

Cost‐effectiveness of positron emission tomography‐CT in the evaluation of cancer of unknown primary of the head and neck

“…Survival estimates were obtained in those who received primary CRT. All costs and life expectancy conversions are presented in Table …”