Gallium 68 prostate-specific membrane antigen PET/CT-guided, robotic-assisted, transgluteal prostate biopsy is safe and retrieved specimens adequate for a pathologic diagnosis of cancer in the majo... Background Transrectal US-guided biopsy with or without MRI fusion is performed for diagnosing prostate cancer (PCa) but has limitations. Gallium 68 (68Ga) prostate-specific membrane antigen (PSMA)...

It is challenging to differentiate between tuberculous peritonitis and peritoneal carcinomatosis due to their insidious nature and intersecting symptoms. Computed tomography (CT) is the modality of choice in evaluating diffuse peritoneal disease. We conducted an ambispective analysis of patients suspected as having tuberculous peritonitis or peritoneal tuberculosis between Jan 2020 to Dec 2021. The study aimed to identify the clinical and radiological features differentiating the two entities. We included 44 cases of tuberculous peritonitis and 45 cases of peritoneal carcinomatosis, with a median age of 31.5 (23.5–40) and 52 (46–61) years, respectively (p ≤ 0.001). Fever, past history of tuberculosis, and loss of weight were significantly associated with tuberculous peritonitis (p ≤ 0.001, p = 0.038 and p = 0.001). Pain in the abdomen and history of malignancy were significantly associated with peritoneal carcinomatosis (p = 0.038 and p ≤ 0.001). Ascites was the most common radiological finding. Loculated ascites, splenomegaly and conglomeration of lymph nodes predicted tuberculous peritonitis significantly (p ≤ 0.001, p = 0.010, p = 0.038). Focal liver lesion(s) and nodular omental involvement were significantly associated with peritoneal carcinomatosis (p = 0.011, p = 0.029). The use of clinical features in conjunction with radiological findings provide better diagnostic yields because of overlapping imaging findings.

Localizing the sites of infection in the body is possible in nuclear medicine using a variety of radiopharmaceuticals that target different components of the infective and inflammatory cascade. Gamma(γ)-emitting agents such as [67Ga]gallium citrate were among the first tracers used, followed by development of positron-emitting tracers like 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG). Though these tracers are quite sensitive, they have limited specificity for infection due to their concentration in sites of non-infective inflammation. White blood cells (WBC) labelled with γ or positron emitters have higher accuracy for differentiating the infective processes from the non-infective conditions that may show positivity with tracers such as 18F-FDG. We present a pictorial review of potential clinical applications of PET/CT using 18F-FDG labelled WBC.

⁶⁸Ga-labeled prostate-specific membrane antigen is a novel radiotracer for imaging of prostate cancer. We report a hormonally treated patient with prostate carcinoma, presenting with lower urinary tract symptoms and rising prostate-specific antigen levels, who underwent ⁶⁸Ga-labeled prostate-specific membrane antigen PET/CT for suspected recurrence. No tracer avid lesion was noted in the prostate gland and locoregional area. However, intense tracer avid heterogeneously enhancing soft tissue lesion with cystic areas and coarse calcifications was seen in the anterior mediastinum. PET/CT-guided biopsy from the mediastenal lesion revealed type B2 thymoma.

Breast is unusual site for metastasis from malignant tumors though may be the first manifestation of extra-mammary malignancy with primary typically arising from lung, melanoma, ovary and lymphoma. Breast metastasis is extremely rare from thyroid carcinoma and may take years to develop as differentiated thyroid carcinoma are usually indolent, slow growing and metastasize to lymph nodes, lungs and bones. Here is a middle-aged woman (post-subtotal thyroidectomy for multi-nodular goitre 24 years ago) showing discordant FDG and iodine avidity in proven metastatic disease involving lymph nodes, bones, spleen and breast on whole-body radioiodine and FDG-PET/CT due to tumor heterogeneity.