Nocardia masquerading as pulmonary malignancy in a patient with adult-onset immunodeficiency on 18F-FDG PET/CT.

A 77-year-old man with a history of left nephrectomy for renal cell carcinoma and partial hepatectomy for cholangiocarcinoma underwent 18F-FDG PET/CT for assessment of an irregular lung lesion. FDG-PET demonstrated development of an intensely avid spiculated left lower lobe pulmonary lesion and intensely avid left pulmonary hilar nodes, raising suspicion for a malignancy. Eleven days following the PET study, the patient was admitted to hospital with an altered mental state. CT brain revealed diffuse round hyperdensities within the brain parenchyma. Microbiology of the lung lesion was positive for Nocardia Beijingensis and he was subsequently diagnosed with disseminated nocardiosis.

Prostate cancer recurrence in the urethra with low PSA.

When localised prostate cancer recurs after treatment, it occurs predictably in sites such as the prostatic bed, pelvic lymph nodes, spine, lung, and liver. Urethral metastasis of prostate cancer is exceedingly rare. We report a case of urethral recurrence of prostate cancer presenting as new lower urinary tract symptoms in an 82-year-old male 10 years after robotic radical prostatectomy with a very low PSA level of 0.05µg/L. This rare case highlights the need to maintain a degree of suspicion for prostate cancer recurrence in patients with a late onset of or changing lower urinary tract symptoms after radical prostatectomy.

Diagnostic accuracy of bone scan at different PSA levels in biochemical recurrence of prostate cancer.

OBJECTIVE: To determine the diagnostic accuracy of Bone Scan at different PSA levels for detecting skeletal metastases in men with biochemical recurrence of prostate cancer. METHODS: We conducted a retrospective review of the statewide RIS-PACS to identify 251 men with biochemical recurrence who underwent both a Bone Scan and Ga68 PSMA PET/CT (within 2 months of each other) between September 2019 and December 2022 at a single institution. The Ga68 PSMA PET/CT report was considered to be the reference standard. RESULTS: The median age was 72 years (IQR 67-76) with a median PSA level of 1 ng/ml (IQR 0.25-2.8). Using Ga68 PSMA PET/CT as the reference standard, 68/251 patients (25%) were positive for osseus metastases. Overall sensitivity and specificity of Bone Scan was 51% (95% CI 40-64%) and 99% (95% CI 98-100%) respectively. Using PSA banding, a PSA threshold of 20 ng/ml provided the greatest discriminatory benefit with sensitivity of the Bone Scan below the threshold being 46% (95% CI 33-59%) and above the threshold being 89% (95% CI 68-100%). Specificity remained consistently high both below and above this threshold. CONCLUSION: Bone Scan provides greater diagnostic accuracy for detecting skeletal metastases in biochemical recurrence when the PSA level is above 20 ng/ml. This knowledge is valuable in optimising imaging algorithms in biochemical recurrence, particularly in regions where PSMA PET/CT is less readily available or affordable.

Intra-individual comparison of prostate-specific membrane antigen positron emission tomography/computed tomography versus bone scan in detecting skeletal metastasis at prostate cancer diagnosis.

OBJECTIVES: To compare the diagnostic performance and radiological staging impact of 68 Ga-prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) compared to 99 Tc whole-body bone scan (WBBS) for the detection of skeletal metastasis in the primary staging of prostate cancer (PCa). PATIENTS AND METHODS: A prospective institutional database was retrospectively examined for patients who underwent both PSMA PET and WBBS within a 1 week interval for PCa primary staging. Lesions were categorised as 'negative', 'equivocal', or 'definite' based on nuclear medicine physician interpretation. Metastatic burden was characterised for each imaging modality according to three groups: (i) local disease (no skeletal metastases), (ii) oligometastatic disease (three or fewer skeletal metastases), or (iii) polymetastatic disease (more than three skeletal metastases). RESULTS: There were 667 patients included. The median (interquartile range) prostate-specific antigen level was 9.2 (6.2-16) ng/mL and 60% of patients were high risk according to a modified D'Amico risk classification. The overall distribution of skeletal metastasis detection changed across the two scans overall (P = 0.003), being maintained within high-risk (P = 0.030) and low-risk (P = 0.018) groups. PSMA PET/CT identified more definite skeletal metastases compared to WBBS overall (10.3% vs 7.3%), and according to risk grouping (high: 12% vs 9%, intermediate: 4% vs 1%). Upstaging was more common with PSMA PET/CT than WBBS (P = 0.001). The maximum standardised uptake value (SUVmax ) of the primary tumour was associated with upstaging of skeletal metastases on PSMA PET/CT (P = 0.025), while age was associated with upstaging on WBBS (P = 0.021). The SUVmax of the primary tumour and metastases were both higher according to extent of metastatic disease (P = 0.001 and P < 0.001, respectively). CONCLUSIONS: More skeletal metastases were detected with PSMA PET/CT than WBBS, resulting in a higher upstaging rate mostly in high-risk patients. The SUVmax of the primary tumour and metastases was associated with upstaging.

Peritoneal Carcinomatosis From Metastatic Prostate Cancer Identified on 68 Ga-Prostate-Specific Membrane Antigen PET/CT.

ABSTRACT: A 69-year-old man with locally advanced prostate adenocarcinoma (Gleason score 9), who had completed hormone therapy and definitive radiotherapy, presented to hospital with abdominal pain and distension. A CT scan of the abdomen and pelvis revealed ascites and extensive peritoneal/omental nodules. Serum prostate-specific antigen was not raised (0.07 µg/L). 68 Ga-prostate-specific membrane antigen (PSMA) PET/CT demonstrated PSMA-avid disease in the prostate and widespread PSMA-avid peritoneal/omental and liver metastases but with no PSMA-avid bony metastases. Peritoneal nodule biopsy confirmed metastatic prostate cancer.

A Comparative Review of Pregnancy and Cancer and Their Association with Endoplasmic Reticulum Aminopeptidase 1 and 2.

The fundamental basis of pregnancy and cancer is to determine the fate of the survival or the death of humanity. However, the development of fetuses and tumors share many similarities and differences, making them two sides of the same coin. This review presents an overview of the similarities and differences between pregnancy and cancer. In addition, we will also discuss the critical roles that Endoplasmic Reticulum Aminopeptidase (ERAP) 1 and 2 may play in the immune system, cell migration, and angiogenesis, all of which are essential for fetal and tumor development. Even though the comprehensive understanding of ERAP2 lags that of ERAP1 due to the lack of an animal model, recent studies have shown that both enzymes are associated with an increased risk of several diseases, including pregnancy disorder pre-eclampsia (PE), recurrent miscarriages, and cancer. The exact mechanisms in both pregnancy and cancer need to be elucidated. Therefore, a deeper understanding of ERAP's role in diseases can make it a potential therapeutic target for pregnancy complications and cancer and offer greater insight into its impact on the immune system.

Comparison between PSMA PET/CT and MRI for Characterizing Hepatocellular carcinoma: A Real-World Study.

Prostate specific membrane antigen (PSMA) is expressed by hepatocellular carcinoma (HCC). PSMA PET/CT has potential as an imaging agent for the detection of HCC including early diagnosis and monitoring for recurrence following surgical resection. This study aims to compare PSMA PET to standard surveillance imaging in the detection of HCC. Patients with suspected or treated HCC were prospectively recruited from a tertiary hospital outpatient clinic. In addition to routine surveillance imaging as recommended by the multidisciplinary team, a PSMA PET/CT was performed. Imaging and clinical characteristics were compared over a follow-up period of up to 12 months. In a cohort of 19 patients with known HCC or suspected recurrent HCC, PSMA PET/CT had similar efficacy to MRI for the detection of HCC, with a sensitivity of 91% and a specificity of 70% and sensitivity of 87% and a specificity of 73% for PSMA PET/CT and MRI, respectively. PSMA PET/CT had a higher negative predictive value of 90%. In this relatively large single centre study, PSMA is shown to have promising equivalence in performance and its role should be further evaluated in multi-centre prospective trials.

Iron Polymaltose Infusion Effects on Bone Scintigraphy and Remodeling.

ABSTRACT: A 73-year-old woman with metastatic breast cancer and known widespread skeletal metastases was referred for bone scintigraphy. Delayed images acquired at 2 and 5 hours postinjection of 30 mCi (1089 MBq) 99mTc-HDP demonstrated markedly reduced bony uptake, markedly increased renal activity, and significantly increased soft tissue accumulation. By contrast, appropriate skeletal uptake of 99mTc-HDP was seen in prior bone scans. The patient had been treated for iron deficiency anemia with an infusion of 1 g of iron polymaltose approximately 22 hours before injection of 99mTc-HDP. This phenomenon may be due to transient reduced bone resorption with increased FGF23 release secondary to IV iron supplementation.

Steroid responsive inflammatory myofibroblastic tumor of the lung evaluated by FDG PET/CT imaging.

A 68-year-old gentleman was referred for 18F-FDG PET/CT for a pulmonary mass in the left upper lobe which demonstrated intensely FDG-avid confluent pulmonary consolidation in the left upper lobe (SUVmax 15.1). Histopathologic biopsy of the left upper lobe lung mass was consistent with inflammatory myofibroblastic tumor (IMT). The patient was started on steroid treatment in conjunction with antibiotics. Follow-up FDG PET/CT 3 weeks after commence of treatment showed remarkable response of the IMTs to therapy with much less avid FDG uptake (SUVmax 5.4) and marked improvement in the pulmonary consolidation. Nevertheless, the patient underwent left upper lobe lobectomy due to evidence of persistent cystic disease and malignant potential associated with IMTs. Final histopathology was consistent with IMT with no evidence of malignancy.

FDG avid pulmonary amyloid nodule in a patient with metastatic renal cell cancer on 18F-FDG PET/CT.

A 60-year-old man with a background of resected clear cell renal cancer and resected colorectal adenocarcinoma presented with a pulmonary mass lesion in the left upper lobe which was avid on 18-F FDG PET/CT. Needle biopsy confirmed metastatic renal cell cancer, which was surgically excised with wedge resection. Follow-up imaging 6 months later demonstrated a second slowly enlarging subcentimeter nodule in the contralateral lung with increasing FDG avidity, suspicious of further small volume oligometastatic disease. Following surgical resection of the second pulmonary lesion, histopathological examination demonstrated nodular pulmonary amyloidosis and no evidence of malignancy.

Disseminated sarcoidosis involving lymph nodes, bone and spleen with progressive cardiac sarcoidosis on 18F-FDG PET/CT and cardiac MRI.

A 63-year-old lady with a background of ischemic heart disease was referred for 18F-FDG PET/CT for multiple lytic bone lesions which showed disseminated FDG avid lesions in the skeleton, nodal stations as well as spleen simulating advanced malignancy such as diffuse lymphomatous disease. A diagnosis of sarcoidosis was pathologically confirmed with bone biopsy. Following treatment, repeat PET/CT revealed significant regression of FDG avid lesions, however prominent uptake in the lateral ventricular wall was suspicious for active cardiac sarcoidosis, particularly given recurrent chest pain. This was confirmed on cardiac MRI and correlation with PET enabled discrimination between ischemic and non-ischemic fibrosis.

Atypical metastatic lung cancer of the right ventricle on FDG PET/CT.

Although primary cardiac tumours are extremely uncommon, secondary tumours or cardiac metastasis are not. We present a 68-year-old gentleman with squamous cell carcinoma of the right lower lobe with bony metastasis to the right clavicle who was treated with radiotherapy to the lung and clavicle as well as combination immunotherapy (Pembrolizumab) and chemotherapy (Carboplatin/Paclitaxel). Despite completing the above treatment regime, 18F-FDG PET/CT scan showed progression with two new sites of metastasis including a focus in the lateral wall of the right ventricle which correlate to a soft tissue density mass on CT as well as a FDG avid mass in the left masseter. Identification of cardiac lesions with 18F-FDG PET/CT maybe challenging with routine preparation due high physiological FDG uptake in the myocardium and significant variability, nevertheless, focal FDG uptake in the heart should be carefully assessed for the possibility of cardiac metastasis.

Solitary Femoral Nodal Metastasis Identified With 68Ga-Prostate-Specific Membrane Antigen PET/CT.

ABSTRACT: A 66-year-old man was referred for a 68Ga-prostate-specific membrane antigen (PSMA) PET/CT scan for primary staging of Gleason 8 prostatic adenocarcinoma. The PET/CT images confirmed PSMA activity in the bilateral prostatic apex in keeping with the known malignancy. An intensely PSMA-avid focus was also noted in a nonenlarged right femoral lymph node with no evidence of PSMA-avid metastatic disease elsewhere. Subsequent core biopsy and histopathology confirmed a solitary metastatic focus of prostatic adenocarcinoma in a right femoral lymph node.

68Ga-Prostate-Specific Membrane Antigen Uptake in Dissecting Abdominal Aortic Aneurysm.

An 81-year-old man with prostate adenocarcinoma (Gleason 4 + 3 = 7) treated with brachytherapy and intermittent androgen deprivation therapy was referred for serial Ga-prostate-specific membrane antigen (PSMA-HBED-CC) PET/CT scans for rising prostate-specific antigen. Findings were suggestive of local prostatic recurrence and nodal metastases. An incidental PSMA-avid focus was noted in the anterior wall of an infrarenal aortic aneurysm, with a contrast-enhanced hyperdense region surrounded by a semilunar hypodense region anteriorly, consistent with enlarging dissecting thrombus. Increased PSMA avidity in atherosclerotic hypertensive lesions may relate to active plaque instability, indicating a need for further evaluation.

68Ga-Prostate-Specific Membrane Antigen Uptake in Cerebral Tuberculosis.

A 71-year-old man with a history of high-risk prostate adenocarcinoma (Gleason score 4 + 5 = 9) treated with brachytherapy in 2016 was referred for a Ga-prostate-specific membrane antigen (PSMA)-HBED-CC PET/CT scan for suspected cancer recurrence on a background of slowly rising serum prostate-specific antigen (0.95 ng/mL; reference, <0.2 ng/mL). This revealed PSMA-avid dura-based hyperdense lesions in the brain, suggestive of cerebral metastases. Biopsy demonstrated the presence of acid-fast bacilli, and with further clinical and microbiological testing, a diagnosis of PSMA-avid cerebral tuberculous mycobacterium infection was made.

False-Positive 18F-FDG PET/CT Uptake in Unilateral Lactation.

A 31-year-old woman (7 months postpartum and lactating) with multiple sclerotic bone lesions was referred for an 18F-FDG PET/CT scan for characterization. The scan demonstrated unilateral diffuse intense FDG uptake corresponding to dense soft tissue in the right breast, likely related to secretory hyperplasia. On further questioning, it was made apparent that she had only been breastfeeding from the right breast. While the left breast also demonstrated dense soft tissue to a lesser degree, no significant FDG uptake was seen. The sclerotic bone lesions were not FDG avid, likely due to a separate non-FDG avid benign condition or bony metastases from a non-FDG avid primary malignancy. This was reinforced by the fact that subsequent investigations including serial bilateral breast ultrasound and percutaneous biopsy demonstrated no definite evidence of malignancy in the bilateral breasts. The histopathology findings of an open surgical biopsy of sclerotic lesions in the left posterior ilium were also nonspecific, favouring bone dysplasia with no evidence of malignancy.

Pachymeningitis Demonstrated on Gallium SPECT/CT Scan.

A 34-year-old woman presented with a 3-month history of right-sided headaches associated with photophobia and pulsatile tinnitus. Investigations including lumbar puncture revealed elevated opening CSF pressure, increased protein, and presence of monocytosis consistent with an inflammatory/infective process. Brain MRI showed an area of thickened enhancing dura around the venous sinus posteriorly. Ga scintigraphy demonstrated focal intracranial uptake in the posterior occipital region, and biopsy confirmed a chronic inflammatory infiltrate with no granulomas.

Current alternative and complementary therapies used in menopause.

OBJECTIVE: To determine the efficacy and safety of common complementary and alternative medicine (CAM) therapies used to relieve the menopausal symptoms. DESIGN: Comprehensive literature search was conducted through the databases Medline, EMBASE, Cochrane, AMED (Allied and Complementary Medicine), NCCAM (The National Centre for Complementary and Alternative Medicine) to identify relevant monographs in English language. RESULTS: Studies have shown that some therapies such as clonidine, selective serotonin receptor inhibitors (SSRIs) and gabapentin are effective in decreasing the degree and frequency of somatic symptoms in menopause, while phytooestrogens and black cohosh have shown mixed results. Use of Ginseng, evening primrose, Dong Quai or vitamin E appears not to be efficacious for the relieving hot flushes. Other effects of these therapies including possible improvements in mood are yet to be substantiated. INCLUSION CRITERIA: All available human complementary medicine studies on menopausal women with regard to the relief of menopausal symptoms. EXCLUSION CRITERIA: Studies not meeting the inclusion criteria, published in languages other than English or animal studies. CONCLUSION: There is a general lacking of longer-term follow-up beyond the trial lengths of 6-12 weeks in the use of CAM, although women may be taking these medications for many years. Well-designed, randomised control trials are needed to elucidate the true effect of these therapies above the placebo effect.