Value of fused positron emission tomography CT in detecting primaries in patients with primary unknown cervical lymph node metastasis

Abstract

FDG PET-CT is a useful tool to help search for unknown primaries in patients with cervical lymph node metastasis and has an acceptable diagnostic yield for the detection of distant malignancies.

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 …”

Defining risk groups of patients with cancer of unknown primary site and cervical nodal metastases by F‐18 fluorodeoxyglucose positron emission tomography and computed tomography imaging

“…Head and neck cancer continues to pose a significant health burden to Asian countries, and cervical nodal metastases are common in this clinical entity. Notably, mounting evidence indicates that FDG PET/CT may be clinically useful for detecting occult primary neoplasms and/or DM, ultimately influencing the clinical management of this patient group [9,10,16,21–23]. Current curative‐intent treatment plans for patients with malignancies are largely dependent on disease status and the nature of the primary tumor.…”