A 62-year-old man presented with intermittent back pain that became more severe over 2 months.

CT revealed a lytic lesion in L5 (with extension into the epidural space on MRI) and a lesion in the right ilium. Biopsy of the ilium showed atypical large lymphoid/plasmacytoid cells. An [¹⁸F]FDG PET/CT was performed to evaluate the extent of disease. The known right iliac lesion with soft tissue component measuring 5  ×  5 cm is [¹⁸F]FDG avid (SUV_max 26) (Fig. 31.6). The L5 lesion presents lytic component on the left side and a soft tissue component that involves the left foramina (SUV_max 6.9) (Fig. 31.7). Other hypermetabolic bone lesions are seen in the proximal sternum (SUV_max 9), ribs bilaterally, T7 involving the adjacent pleura, T9 and L4 (Fig. 31.8).

[¹⁸F]FDG PET/CT is more sensitive than skeletal X-ray evaluation of bone marrow involvement in patients with multiple myeloma. The technique may be able to predict fracture risk, particularly if the SUV_max is >3.4.

A 72-year-old woman with multifocal ductal carcinoma of the left breast previously treated with lumpectomy, external beam radiation therapy, and chemotherapy 5 years ago. She developed weakness of the right hand.

MRI of the brain revealed multiple supratentorial metastases several of which demonstrated lesional hemorrhage and edema. An extra-axial lesion involving the left cavernous sinus and the middle cranial fossa was also seen, representing a meningioma. [¹⁸F]FDG PET/CT was performed to evaluate the extent of disease (Figs. 31.9 and 31.10). PET/CT fusion images demonstrate five hypermetabolic lesions of the brain with intense [¹⁸F]FDG uptake localized, respectively, in the high left parietal lobe (1.7  ×  1.7 cm, SUV_max 17), left temporo-occipital region (1.2  ×  1.5 cm, SUV_max 15), right frontal cortex (1.3  ×  1.3 cm, SUV_max 16), and right parietal cortex (1.6  ×  1 cm, SUV_max 16) (Fig. 31.10). These supratentorial lesions are suspicious for metastases. A large lobulated lesion (Fig. 31.11) in the left frontal and temporal lobe with a rim of calcification in contact to the sphenoid bone (SUV_max 22) is also seen, suggesting a meningioma, in correlation with MRI. [¹⁸F]FDG PET/CT did not show evidence of recurrent or metastatic disease outside the brain. The patient underwent left temporal superficial brain biopsy and tumor resection which revealed diffuse large cell lymphoma with adjacent meningioma grade 1. The lumbar puncture and bone marrow biopsy were negative for the presence of malignant cells. The patient was treated with combination chemotherapy.

A 9-month-old girl presented with bilateral periorbital ecchymosis, right side exophthalmos, and abdominal distension.

CT revealed a renal mass (8  ×  8 cm), retroperitoneal lymphadenopathy, as well as multiple hepatic and pulmonary lesions. CT of the head showed widespread osseous metastases and right exophthalmus. Biopsy confirmed neuroblastoma (stage IV). [¹²³I]MIBG planar and SPECT/CT images (Fig. 31.12) show a large partially calcified left abdominal mass with pathological radiopharmaceutical uptake, representing the site of primary tumor of adrenal origin. Abnormal foci of MIBG uptake are present in both lobes of the liver, corresponding to hepatic metastasis. Multiple foci of pathological uptake in the axial and the appendicular skeleton are also seen. Bilateral lung nodules do not show focal radiotracer accumulation.

As a part of initial staging [¹⁸F]FDG PET/CT was performed: images demonstrate low [¹⁸F]FDG uptake in the bone marrow of the pelvis and distal femurs and proximal tibiae (Fig. 31.13). The known abdominal mass and liver metastases do not show abnormal uptake. Bone marrow involvement was confirmed by bone marrow biopsies that revealed the presence of neuroblastoma without MYC-gene amplification.

The patient was treated with neoadjuvant chemotherapy and surgery (left adrenalectomy and retroperitoneal lymphadenectomy). Follow-up evaluation after adjuvant chemotherapy showed stable disease. [¹²³I]MIBG scan demonstrates abnormal uptake in the axial and the appendicular skeleton and in the liver (Fig. 31.14). This case demonstrates that [¹⁸F]FDG PET/CT is not as sensitive as MIBG imaging in many patients with neuroblastoma.

A 48-year-old women with inflammatory breast cancer previously treated by mastectomy and low-level axillary dissection, followed by chemotherapy and chest wall irradiation, presented with signs of recurrent breast cancer.

Findings on physical examination included a left chest wall mass with reddened overlying skin and clearly palpable axillary adenopathy. Initial staging suggested chest wall, axillary, and supraclavicular/cervical nodal disease. Core biopsy of the chest mass showed it to be high grade, ER (−), PR (−), and HER2/Neu (+) breast cancer. Skin biopsy confirmed dermal infiltration. A combination of systemic therapy and selective re-irradiation was being considered. [¹⁸F]FDG PET/CT was ordered as part of her initial staging ­studies. Coronal images of [¹⁸F]FDG-PET (Fig. 31.15a, b) and PET-CT fusion (Fig. 31.15c) demonstrate recurrent disease extending into the chest wall, axillary, supraclavicular, cervical, internal mammary (IM), mediastinal, and hilar lymph nodes. Image (Fig. 31.15a) shows a large L chest mass extending to the chest wall and involving skin, seen in the lateral extent of abnormal [¹⁸F]FDG uptake. In the axilla, there is diffuse, mass-like spread along the tissue planes that were part of her prior axillary dissection. PET and PET-CT fusion (Fig. 31.15b, c) also demonstrate the extension of axillary nodal disease into the deep axilla and beyond into bulky supraclavicular and cervical nodal disease. In addition, there is abnormal uptake in paratracheal, prevascular, bilateral hilar, and contralateral axillary nodal beds, strongly ­suggestive of metastatic cancer. An otherwise physiologic distribution of [¹⁸F]FDG uptake is seen, including uptake in the vocal cords, a normal variant.

Fig. 31.15 Coronal images of [¹⁸F]FDG-PET (a) large L chest mass and (b) axillary nodal disease. (c) PET-CT fusion of axillary nodal disease

The contralateral axillary disease seen on [¹⁸F]FDG PET/CT was confirmed by needle biopsy. Given the extensive spread of disease, additional radiotherapy was not used, and the patient was treated by systemic therapy alone using a combination of chemotherapy and HER2-directed therapy. This case demonstrates the value of [¹⁸F]FDG PET/CT used for restaging of recurrent and/or metastatic breast cancer and how [¹⁸F]FDG PET/CT can help direct treatment in this patient population.

A 38-year-old man presented with left-sided abdominal pain.

A CT scan showed a large retroperitoneal mass in the periaortic region. [¹⁸F]FDG PET/CT scan was done for staging. [¹⁸F]FDG PET/CT images demonstrate a large [¹⁸F]FDG-avid retroperitoneal multilobulated mass measuring 14  ×  8  ×  13 cm (SUV_max 41) (Fig. 31.16). Hypermetabolic adenopathy in the left neck, left paratracheal region, right retrocrural as well as para-aortic and para-caval lymph nodes are also seen (Fig. 31.17). Biopsy revealed a ­well-differentiated neuroendocrine tumor, consistent with paraganglioma.

The patient was treated with external beam radiation ­therapy. The [¹⁸F]FDG PET/CT performed to evaluate the response to therapy shows significant decrease in [¹⁸F]FDG avidity and size of irradiated left supraclavicular and retroperitoneal masses (Fig. 31.18).

A 72-year-old man presented with productive cough and shortness of breath.

Chest x-ray showed an infiltrate in the right middle lobe. The patient was treated with antibiotics and his symptoms improved. A subsequent CT scan revealed a right hilar mass with mediastinal and hilar adenopathy. Endobronchial biopsy demonstrated lung adenocarcinoma. An [¹⁸F]FDG-PET/CT was performed for staging (Fig. 31.19). [¹⁸F]FDG PET/CT images showed radiopharmaceutical uptake in the known primary lesion (SUV_max 16) with central photopenia, compatible with necrosis (Fig. 31.20). Additionally, an [¹⁸F]FDG-avid right hilar mass (SUV_max 11) was seen, causing collapse of the lobe due to occlusion of the middle lobe bronchus (Fig. 31.21). Hypermetabolic right and left paratracheal and subcarinal lymph nodes were also present (Fig. 31.22).

The patient was treated with chemo- and radiation therapy. [¹⁸F]FDG PET/CT performed to evaluate response to treatment demonstrated a decrease in the size and intensity of the hypermetabolic right hilar mass (Fig. 31.23).

This 85-year-old male patient was referred following a chest x-ray and CT performed at a 1 month interval and showing a 5  ×  5  ×  4 cm RLL (right lower lobe) mass. The differential diagnosis included a pulmonary abscess, round actelectasis, and pneumonia.

Biopsy indicated the presence of NSCLC. PET/CT was performed for staging (Fig. 31.24a). Selected transaxial CT, PET and fused PET/CT slice, and MIP (maximum intensity projection) image (lower right) show an [¹⁸F]FDG-avid RLL mass (SUV_max 11.3) with a photopenic/necrotic center and an avid right hilar node (SUV_max 4.1), corresponding to T2aN1M0 disease. Due to a history of ischemic heart disease and stage 3 renal failure, the patient was considered to be at high risk for surgery and was referred for additional investigations including a cardiology work-up and CT of the brain (which the patient refused to perform). During this prolonged presurgical evaluation, the patient developed RLL pain and cough and was referred to a repeat PET/CT at a 3 months interval to the first study with the suspicion of local tumor infiltration. The second PET/CT study (Fig. 31.24b) showed marked disease progression. The main tumor mass has increased in size to 6.5 cm in diameter and is invading the chest wall. There are multiple new [¹⁸F]FDG-avid right lung lesions, pleural deposits (arrow), an anterior mediastinal node, and left adrenal metastasis (open arrow). These findings correspond to T4N2M1b disease (Fig. 31.24b).