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Focal myositis is a rare benign inflammatory pseudotumor that can mimic malignancy, clinically and on imaging. A 34-year-old man presented with a 3-week history of sudden-onset, nontender, left upper neck mass that was nonresolving with antibiotics. Anatomical imaging was concerning for a sarcoma of the sternocleidomastoid muscle with possible regional nodal metastases and surrounding inflammatory change. F-FDG PET/CT showed marked FDG uptake extending around the anterior border of the sternocleidomastoid muscle with no FDG-avid local nodal disease. Core biopsy of the sternocleidomastoid muscle and adjacent node revealed inflammatory changes. A diagnosis of focal inflammatory myositis was made.

A previously well 48-year-old male patient presented with several months of weight loss, fever, massive hepatosplenomegaly, and pancytopenia. A provisional diagnosis of lymphoma could not be confirmed on blind lymph node or bone marrow biopsies. Referral for 18F-FDG PET was made to identify an appropriate biopsy site. Focal uptake in multiple splenic lesions was seen, with normal FDG uptake elsewhere in the body. Splenectomy was then performed and histology revealed leishmaniasis, with no evidence of lymphoma. Focally FDG avid splenic deposits have never been reported in leishmaniasis and were likely due to nodular red pulp expansion.

A 76-year-old man was incidentally diagnosed with prostate lymphoma following transurethral resection of the prostate for prostatism. Staging F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) revealed markedly increased FDG uptake in the prostate, with no evidence of other disease. Following combination chemotherapy, restaging FDG-PET/CT demonstrated a complete metabolic response. The patient subsequently achieved prolonged remission on follow-up. Because of its rarity, FDG-PET in predicting outcome after therapy has not been validated for primary prostate lymphoma. This case highlights the potential of FDG-PET/CT in not only evaluation of disease extent but also prognostication of primary lymphoma of the prostate.

A 46-year-old woman with known Graves' disease underwent a Tc-99m tetrofosmin myocardial perfusion scan (MPS) for investigation of chest pain. The study showed a mildly dilated left ventricle but no evidence of myocardial ischemia. Routine planar images of the thorax showed prominent, diffu

A 56-year-old patient was referred for FDG PET/CT with a right preauricular lymph node fine-needle biopsy, suggesting poorly differentiated carcinoma and no obvious primary lesion. There was intense FDG uptake in the right preauricular nodule. The node was excised, and formal histology demonstrated a benign pilomatricoma rather than malignancy. Pilomatricoma is uncommon in adults and an unusual cause for marked FDG uptake, likely due to foreign body inflammation. Pilomatricoma can be either benign or malignant. The marked FDG uptake demonstrated in our patient with benign pilomatricoma also suggests that FDG PET cannot reliably grade this rare condition.

A 29-year-old woman presented with a new right supraclavicular mass on a background of resection of a malignant melanoma from her right shoulder before 4 years. F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging revealed uptake in a right supraclavicular node and the inferior pole of the left lobe of the thyroid gland. Subsequent resection and histology of the right supraclavicular node and the left lobe of the thyroid gland demonstrated metastatic melanoma and palpation thyroiditis, respectively. A number of malignant and benign pathologies of the thyroid demonstrate FDG uptake, with 75% being benign. To our knowledge, the findings of palpation thyroiditis on FDG PET/CT have never been previously described.

Rib and sternal fractures are relatively common following conventional cardiopulmonary resuscitation (CPR). This case demonstrates the 18F-FDG PET/CT appearances of typical CPR-related multiple rib and sternal fractures in a 55-year-old man with suspected cardiac sarcoidosis. The PET/CT scan was performed to assess disease activity of cardiac sarcoidosis, and no active cardiac inflammation was detected. The patient initially presented with an out-of-hospital cardiac arrest and successfully received bystander CPR.

Crystal arthropathies such as gout often present as an acute inflammatory monoarthritis. There could be a low-grade fever but patients are not usually systemically unwell. Septic arthritis is included in the differential diagnosis of both typical and atypical presentations of gout and could coexist with gout. A 46-year-old Tongan man with alcoholic liver disease and cardiomyopathy presented with fevers up to 39°C and severe polyarticular joint pain affecting large and small joints causing marked restriction of movement. Urgent investigations were performed to establish the diagnosis.