PET-BT'de Yüksek Düzeyde FDG Tutulumu Olan Mediastinal Lenfadenopatilerde Granülamatöz Hastalýklar Düþünülmelidir

Granülomatöz hastalýklar ülkemizde oldukça sýk görülmektedir. Tüberküloz ve sarkoidoz bu hastalýklar içerisinde en baþta gelenlerdir. Tüberküloz sýklýkla akciðerleri tutmasýna raðmen bazý olgularda mediastinal lenf tutulumu þeklinde de ortaya çýkmaktadýr. Sarkoidoz ise sýklýkla mediastinal ve hiler lenfadenopatiler þeklinde karþýmýza çýkmaktadýr. Bu makalede PET-BT incelemelerinde mediastinal maligniteyi taklit eden, yüksek düzeyde F-18 FDG tutulumu olan granülamatöz lenfadenit olgularýný sunmayý amaçladýk. Kliniðimize PET-BT görüntülerinde patolojik FDG tutulumu olan mediastinal LAP nedeniyle üç hasta baþvurdu. Hastalarýn ikisinde öksürük ve nefes darlýðý þikayeti, birisi meme kanseri, uterus kanseri ve tiroit kanserinden ameliyat edilmiþti. Ýki olgunun videomediastinoskopik lenf nodu biyopsi sonucu kazeifiye granülomatöz iltihabi olay olarak rapor edildi. Nefes darlýðý nedeniyle tetkik edilen hastanýn PET-BT'de subkarinal lenf nodu ve sol interlober lenf nodlarýnda patolojik FDG tutulumu izlendi. Bu olgunun videomediastinoskopik lenf nodu biyopsi sonucu non-kazeifiye granülomatöz iltihabi olay olarak rapor edildi. Ülkemizde tüberküloz ve sarkoidoz gibi granülamatöz hastalýklar yanlýþ pozitif FDG PET nedenleri arasýnda en sýk görülenlerdir. Olgularýmýzdaki gibi yüksek FDG tutulumu olanlarda maligniteyi ekarte edebilmek için doku biyopsisi gereklidir.

Granulomatous Diseases Should be Considered in Mediastinal Lymphadenopathies with High F-18 FDG Uptake on PET-CT Scans

Granulomatous diseases are quite common in our country; tuberculosis (TB) and sarcoidosis are the most common. TB mostly involves the lungs; however, in some cases, it may involve the mediastinal lymph nodes. Sarcoidosis, on the other hand, often reveals itself as mediastinal or hilar lymphadenopathy (LAP). Presently described are cases of granulomatous lymphadenitis that mimicked mediastinal malignancy in positron emission tomography-computed tomography (PET-CT) scanning and had high fludeoxyglucose (FDG) uptake. Three patients whose PET-CT scans revealed pathological FDG uptake due to mediastinal LAP were admitted to our clinic. Two had cough and dyspnea, and third had operated breast cancer, uterine cancer, and thyroid cancer. Videomediastinoscopic biopsies of 2 patients were reported as caseating granulomatous inflammation. In patient who was examined for dyspnea, PET-CT revealed pathological FDG uptake in subcarinal lymph nodes and the left interlobar lymph nodes. Videomediastinoscopic lymph node biopsy of this patient was reported as non-caseating granulomatous inflammation. Granulomatous diseases, such as TB and sarcoidosis, are the most common cause of false-positive FDG PET scans in our country. In cases with high FDG uptake, tissue biopsy can exclude malignancy.