Nuclear medicine - 18FDG-PET/CT
18FDG-PET/CT
There is intense FDG activity corresponding to an irregular soft tissue density in the left upper lobe that extends from the left hilum to the level of the manubrium. The mass measures 60 x 20 x35mm. FDG uptake in the mass is heterogeneous, particularly anteriorly, suggesting a central tumour with post obstructive atelectasis. A number of smaller FDG avid satellite lesions are present, the largest in the inferior lingula.
The left hilum is markedly FDG avid consistent with hilar nodal involvement. There is FDG avid interstitial thickening extending away from the hilum concerning for lymphangitis carcinomatosis. Enlarged AP window nodes are not FDG avid. No axillary or supraclavicular nodes identified.
At least 7 right-sided nodules and one right upper lobe mass, measuring 30mm, show variable FDG uptake depending on size. They are consistent with contralateral metastases.
There is a large left pleural effusion that demonstrates faint peripheral FDG avidity suspicious for malignant effusion. This has increased in size since external CT-chest.
There are several intensely FDG avid bony lesions consistent with metastases. A C5 vertebral body lesion that extends anteriorly into soft tissues demonstrates cortical thinning and erosion and is at risk of pathological fracture. Further bony metastases demonstrated in the left lateral 11th rib and right L4 pedicle. Mildly increased FDG activity associated with linear sclerotic change in the left 9th and 10th ribs may also reflect metastases in this clinical picture however may also reflect old fractures.
No metabolically active solid organ metastases are demonstrated.
A right 11mm hypodense thyroid lesion that is mildly FDG avid is suspicious for thyroid malignancy/adenoma.
Asymmetric FDG activity associated with vocal cords (right > left) is probably physiologic.
Conclusion: 1. Over-all the findings are best explained by a primary right-left upper lobe lung primary with metastases to contralateral lung and bone. The primary lesion should be amenable to percutaneous biopsy targeting most FDG avid component.
2. C5 metastases may warrant more urgent direct therapy as is at risk for pathological fracture.
2. Progressive increase in the left pleural effusion since prior imaging with partial left lower lobe collapse.
3. Thyroid nodule, mildly FDG avid, suspicious for thyroid malignancy/adenoma. Ultrasound +/- histopathological could be considered.
4. Asymmetric FDG Activity in vocal cords (right > left) of uncertain aetiology, likely related to left recurrent laryngeal nerve infiltration and left palsy.