Unusual Uptake of Prostate Specific Tracer 68Ga-PSMA-HBED-CC in a Benign Thyroid Nodule.

68Ga-Prostate specific membrane antigen- N,N'-bis[2-hydroxy-5-(carboxyethyl)benzyl]ethylenediamine-N,N'-diacetic acid- positron emission tomography/computed tomography or 68 Ga- HBED-CC-PSMA PET/CT, popularly known as PSMA PET/CT, is able to detect a small volume of recurrent prostate carcinoma (PC) when there is a prostate specific antigen (PSA) rise on follow-up after prostatectomy or other definitive treatment for PC. The use of PSMA PET/CT in the initial staging in PC is uncertain at this time. Clinical studies are underway to define its exact role in the management of the disease. At the same time it is important to be aware of unexpected sites of uptake of this ligand. We present here the case of a 62-year-old male patient who underwent prostatectomy for adenocarcinoma prostate. He also had a long-standing left solitary thyroid nodule (STN). Four months after surgery, he had a rising trend in serum PSA levels on three occasions, but the absolute value was less than 4 at all times. He underwent a 68Ga-PSMA-HBED-CC PET/CT, but it did not reveal any recurrent/metastatic site of disease. However, there was increased tracer uptake in the left STN. Fine needle aspiration cytology revealed features of atypia of undetermined significance, Bethesda category III. The patient underwent a left hemithyroidectomy and the histopathology showed features of a follicular adenoma.

Detection of brain metastasis with 68Ga-labeled PSMA ligand PET/CT: a novel radiotracer for imaging of prostate carcinoma.

Brain metastasis in prostate cancer is rare and not expected at initial presentation especially when the patient is asymptomatic for the same. A 45-year-old male patient undergoing initial evaluation for newly diagnosed prostatic adenocarcinoma was referred to our department for 99mTc-MDP bone scintigraphy. As part of the study protocol, he also underwent Glu-NH-CO-NH-Lys-(Ahx)-[Ga-68(HBED-CC)] (68Ga-PSMA) PET/CT, which revealed tracer accumulation in brain lesions, apart from localization in the primary, lymph node, and bone metastases. A subsequent MR evaluation confirmed brain metastases.

Radiation-Induced Esophagitis Masquerading as Disease Progression in Case of Esophageal Carcinoma: A Diagnostic Dilemma Solved on Follow-up FDG PET/CT.

Radiation esophagitis is one of the commonest complications of the radiotherapy involving esophagus. It is characterized by diffuse radiotracer uptake in the esophagus on ¹8F-FDG PET/CT. Thus, it can be often confused with the esophageal malignancy. We present the sequential ¹8F-FDG PET/CT images of a 45-year-old woman with locally advanced squamous cell carcinoma of the esophagus who developed radiation esophagitis after chemoradiotherapy. It was confused with the progression of the disease, and the dilemma was resolved by the follow-up PET/CT.

Synchronous thoracic and abdominal enteric duplication cysts: Accurate detection with (99m)Tc-pertechnetate scintigraphy.

Enteric duplication cysts (EDCs) are uncommon congenital anomalies, which can occur anywhere along the gastrointestinal tract and vary greatly in presentation, size, location and symptoms. Ectopic gastric mucosa is reported to be found in 20-30% of these duplications. (99m)Tc-pertechnetate scintigraphy is a useful modality for preoperative localization of the ectopic functioning gastric mucosa in the EDCs. We report a case where (99m)Tc-pertechnetate scintigraphy was useful in detecting synchronous thoracic and abdominal duplication cysts with functioning gastric mucosa thus having an impact on the patient management.

Metastatic poorly differentiated prostatic carcinoma with neuroendocrine differentiation: negative on 68Ga-PSMA PET/CT.

Glu-NH-CO-NH-Lys-(Ahx)-[Ga-68(HBED-CC)], abbreviated as Ga-PSMA, is a novel radiotracer undergoing evaluation for PET/CT imaging of prostate carcinoma. Its major advantage is the sensitive detection of lesions even at low prostate-specific antigen level and high target-to-background ratios obtained in metastatic lesions, which is better than that obtained with F-fluoromethylcholine. We present the case of a 28-year-old man with poorly differentiated prostate carcinoma with neuroendocrine differentiation, whose lesions did not show significant Ga-PSMA localization. As literature on utility of Ga-PSMA PET/CT for imaging prostate carcinoma grows, it is important to be aware of potential false negatives that could influence study results.

Metastatic superscan on (99m)Tc-MDP bone scintigraphy in a case of carcinoma colon: Common finding but rare etiology.

Bone scintigraphy in which there is excessive skeletal radioisotope uptake in relation to soft tissues along with absent or faint activity in the genitourinary tract is known as a 'superscan'. Prostate cancer is the most common malignancy associated with superscan along with others such as lung cancer, breast cancer and haematological malignancies. Here we present the case of a 41 year old woman with carcinoma colon with metastatic superscan on (99m)Tc-MDP bone scintigraphy, a very rare cause for metastatic superscan.

Ciliary body metastasis in a patient with non-small cell lung carcinoma--incidental detection with 18F-FDG PET/CT.

Ciliary body metastasis in a case of lung cancer is very rare. Intraocular metastasis by any cancer most commonly involves choroid followed by iris and ciliary body. We present a case of a 71-year-old male with non-small cell lung cancer who was found to have an 18F-FDG avid right lung mass. Incidentally a focus of abnormal increased 18F-FDG uptake was noted in the region of ciliary body in the right eyeball. The findings were confirmed to be a metastatic lesion in ciliary body on Ultrasonography and MRI. Our case depicts this extremely rare occurrence corroborated by various modalities.

Sertoli Leydig cell tumour of ovary with heterologous element--a case report.

A 16 years old female who presented with abdominal swelling and secondary amenorrhoea was subsequently diagnosed as Sertoli Leydig cell tumour of ovary revealing intermediate differentiation with heterologous element. The case is reported in view of its rarity.