Patient 1 is a 66-year-old male with a history of chronic leukocytosis and 50 pack-year tobacco use who underwent routine virtual colonoscopy, which although negative for colonic neoplasia, did show a 7-cm right hilar mass, bilateral bulky adrenal glands, diffuse adenopathy, and ill-defined non-specific osseous hypodensities involving the sternum, L2, and L3 vertebral bodies. Three weeks after the initial CT, staging PET revealed 18F-FDG-avidity throughout the hilar mass, surrounding lymphadenopathy, manubrium, and L4 vertebral body. Areas of osseous photopenia previously identified amongst the L2 and L3 vertebral bodies were relatively void of 18F-FDG uptake. Subsequent transbronchial fine needle aspiration showed non-squamous non-small cell lung cancer with endocrine features (chromogranin and synaptophysin positive). Two weeks after staging, the patient underwent PET/CT-guided biopsy of a focal region of hypermetabolism involving the majority of the L4 vertebral body (Image 1). Biopsy indicated neuroendocrine carcinoma. Brain MRI showed 15–20 cystic foci of metastatic spread with midline shift and compression of the fourth ventricle. He clinically deteriorated with progressive ataxia and profound weakness, prompting initiation of whole brain irradiation followed by atezolizumab/carboplatin/etoposide. Despite some improvement after radiation and dexamethasone, he decompensated again with inability to eat or swallow pills and ceased returning to clinic for follow-up.
Patient 2 is a 57-year-old previously healthy male with a 35 pack-year smoking history who initially presented to primary care clinic with a week and a half of intermittent left shoulder pain radiating to his upper back awakening him from sleep. CT angiogram in the emergency department discovered diffuse lymphadenopathy with a possible lytic lesion within the T1 vertebral body. 18F-FDG PET/CT revealed stage IV metastatic disease affecting the cervical, supraclavicular, mediastinal, hilar, right internal mammary, retroperitoneal, and iliac lymph nodes. Numerous osseous sites including the entire sternum, T4, T10, right 7th rib, and left iliac wing showed hypermetabolic activity. Spleen CNB showed large B cell lymphoma with indeterminate cell of origin. Initial bone marrow aspiration indicated no involvement; however, follow-up PET/CT-guided CNB of T10 (Image 2) showed CD10+ large B-cell lymphoma, guiding treatment with six cycles of R-CHOP. Mid-treatment PET/CT showed interval resolution of the majority of the previously seen hypermetabolic lesions with few foci of mild residual splenic and osseous hypermetabolism. Five months after initiation of chemotherapy, end-of-treatment PET/CT indicated complete response.
Patient 3 is a 56-year-old male with a long-standing history of gastroesophageal reflux disease and one pint of alcohol consumption daily who initially presented to gastroenterology clinic with 2 months of progressive dysphagia and mid-back pain. Endoscopic evaluation revealed esophageal adenocarcinoma with mucinous features and human epidermal growth receptor factor receptor 2 (HER2) positivity by immunohistochemistry. Subsequent CT demonstrated a few small, nonspecific upper lobe pulmonary nodules without obvious metastatic disease. Initial staging PET/CT confirmed 18F-FDG -avid mass at the gastroesophageal junction with regional lymphadenopathy. Numerous other hypermetabolic foci included subcentimeter left lower lobe pulmonary nodules, right hilar lymph node, mesenteric lymph nodes, descending colon, and multiple osseous lesions within the right humerus, right posterior iliac crest, T6, L3, and left lateral 2nd rib. PET/CT-guided CNB biopsy of the T6 vertebral body (Image 3) revealed metastatic adenocarcinoma. Prior to end-of-therapy with FOLFOX and traztuzumab, the patient transferred care to an out-of-state medical facility, and no further information on the disease course is available.
Patient 4 is a 63-year-old female with a history of a verrucous mass along her left shin initially thought to be seborrheic keratosis temporarily improving with cryotherapy. After its recurrence 2 years later, she presented to dermatology clinic where shave biopsy revealed stage III melanoma with at least 1.8-mm infiltration and ulceration. A surgical oncologist performed wide local excision with sentinel lymph node biopsy, ultimately positive for malignant involvement. On staging PET/CT, inflammatory post-operative changes were identified along the anterior aspect of the left shin in addition to a hypermetabolic focus in the T9 vertebral body without correlating CT features. Further evaluation with MRI showed ill-defined focus of T9 vertebral bone marrow signal changes without discrete margins. PET/CT-guided biopsy of the 18F-FDG-avid region of the T9 vertebral body revealed no findings to suggest malignancy (Image 4). These findings correlated with a traumatic injury of her lumbar spine 5 years prior. Treatment with mivolumab was initiated, and surveillance imaging had not yet been obtained at the time of this review.