The evaluation of hypermetabolic mediastinal–hilar lymph nodes determined byPET/CT in pulmonary and extrapulmonary malignancies: correlation with EBUS-TBNA

Abstract

Background/aim: We aimed to define the optimal SUVmax cut-off value in determination of mediastinal-hilar lymph node metastasis, by comparing positive PET/CT results with the results of endobronchial ultrasound guided transbronchial needle aspiration biopsy (EBUS-TBNA).Materials and methods: Thirty-one patients with malignancy whose PET/CT imaging revealed a hypermetabolic mediastinal and/ or hilar lymph node and who had undergone EBUS-TBNA were evaluated retrospectively. Histopathology was regarded as the gold standard. The diagnostic role of PET/CT in mediastinal/hilar lymph node metastasis was investigated and compared with the results of contrast-enhanced CT.Results: When a SUVmax value of 2.5 was used, the sensitivity, positive predictive value (PPV), and diagnostic accuracy of the PET/CT were 100%, 65.4%, and 65.4% respectively. In the ROC analysis, the SUVmax cut-off value with the highest diagnostic accuracy (75%) was calculated as 6.3, and when this value was considered, the sensitivity, specificity, PPV, negative predictive value, and diagnostic accuracy of the PET/CT were determined as 70.6%, 83.3%, 88.9%, 60%, and 75% respectively (AUC: 0.779). The sensitivity, PPV, and diagnostic accuracy of the thorax CT were calculated as 91.1%, 72%, and 71.1%, respectively. Conclusion:When determining mediastinal-hilar lymph node metastasis via PET/CT, although a SUVmax cut-off value of 6.3 increases specificity and diagnostic accuracy, we think that a SUVmax cut-off value of 2.5 and above give more optimal results in routine practice.

Endobronchial ultrasound‐guided transbronchial needle aspiration cytology in patients with known or suspected extra‐pulmonary malignancies: A cytopathology‐based study

“…Increased 2‐fluoro‐2‐deoxy‐ d ‐glucose uptake on positron emission tomography (PET) is fairly sensitive for metastases (~65%) . However, a significant proportion of infectious and inflammatory diseases also show increased PET uptake, lowering its specificity (~35%) and diagnostic accuracy (~65%) for malignancy .…”

Utility of EBUS-TBNA in PET-positive mediastinal lymph nodes in subjects with extra-thoracic malignancy

“…The limitations of our study include its retrospective single centre nature with a limited sample size, but this compares well with the numbers reported in other studies (31 in the study reported by Kandemir et al). [ 4 ] We could not confirm the reactive lymphadenitis diagnoses with mediastinoscopy, as patients were not willing for more invasive surgical procedures, which is a common observation in malignancy situations. Our numbers are skewed towards benign diagnoses, but this is an important feature to highlight in an endemic tuberculosis situation, which is common in many parts of the world.…”

“…In ETM, a SUV value of ≥6.3 and above is considered malignant, with sensitivity and specificity of 70.6% and 83.3%, respectively. [ 4 ] An accurate tissue diagnoses of PET–positive MLN is vital, for initial staging of primary thoracic or extra-thoracic malignancy or detect recurrence in patients with treated malignancy. However, in PET HM-MLN, there is the confounding possibility of benign disease with inflammatory activity leading to a false-positive high SUV simulating malignancy.…”

Application of positron emission tomography‑computed tomography in the diagnosis of pulmonary ground‑glass nodules

“…In 1997, the Nomenclature Committee of the International Union of Biochemistry defined GGN as a fuzzy density where the bronchi or lung blood vessels remain visible with high-resolution CT (11). Additionally, it refers to a class of non-specific CT signs that have a slightly increased density in high-resolution CT images (12). With regard to pathology, GGN has been identified for a variety of inflammatory conditions, edema, bleeding, fibrosis and tumor lesions (13)(14)(15)(16)(17).…”