Molecular imaging with 68Ga-PSMA PET/CT in high grade glioma: A biomarker for tumour neo-angiogenesis.

There are several promising radiotracers used for both staging and restaging of primary and recurrent brain tumours based on various mechanisms of tracer localization in tumour cells. 68Ga-PSMA PET has extremely low background uptake in normal brain tissue and consequently high tumour-to-brain ratio making it a promising imaging radiotracer for gliomas. 68Ga-PSMA demonstrates utility in evaluating high grade glioma during both initial workup or when suspecting recurrence. Herein the authors evaluate the role of this imaging modality and the potential future it holds in the management of high grade gliomas.

Silent Invader: Cardiac Metastasis From Buccal Squamous Cell Carcinoma.

​Head and neck squamous cell carcinomas (HNSCC) are common malignancies that can metastasize to various distant sites. Cardiac metastasis (CM) from a primary HNSCC is an extremely rare finding that presents a significant challenge due to its association with a poor prognosis and limited treatment options. Due to their rare occurrence, there is no clear consensus on how to diagnose and manage such cases. In this article, we review a patient with complicated CM from buccal squamous cell carcinoma, which was incidentally detected by fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT).

Calcaneus metastasis: a rare presentation of poorly differentiated thyroid cancer.

Summary: A 60-year-old woman presented to our clinic with an acute onset 3 months history of right ankle pain. The patient had a history of poorly differentiated thyroid cancer, which was treated with total thyroidectomy, left lateral neck dissection levels II-V and central neck dissection levels VI-VII followed by postoperative I-131 radioactive iodine (131I) ablation therapy 3.7 GBq 6 months ago. The post-131I WBS showed residual iodine-avid thyroid tissue with no other iodine-avid disease or metastasis. SPECT/CT of the neck and chest showed nonavid bilateral pulmonary nodules, discrete nodal masses in mediastinum and nonavid bone lesions. FDG-PET CT scan showed FDG-avid mediastinal lymph nodes (LN), innumerable non-FDG-avid subcentimetric pulmonary nodules and few FDG-avid lytic lesions in the skeleton. X-ray and MRI of the right ankle showed a well-marginated lytic lesion in the posterior body of calcaneus and 5 × 6 cm soft tissue mass lesion, respectively. The histopathology of the calcaneus mass confirmed a positive immunostaining for thyroid origin which includes thyroglobulin and TTF-1 with PAX-8. Endobronchial mediastinal and bronchial LN biopsy confirmed thyroid cancer metastasis. Gene mutation showed HRAS and GNA13 with a high tumor mutational burden. We describe a rare case of poorly differentiated thyroid cancer in a patient who presented with right ankle pain; we confirmed the cause to be a calcaneus metastasis from the thyroid cancer, with calcaneus being an extremely rare site for bone metastases. Gene mutations points toward treatment with immune checkpoint inhibitors. Learning points: Poorly differentiated thyroid carcinoma (PDTC) usually metastasizes to lung and bone but can rarely occur in the calcaneus. Patients with distant metastases have significantly worse long-term prognosis. Radiotherapy is effective in reducing the metastatic pains as well as reducing the size of the metastasis. PAX-8 staining can be used to differentiate thyroid carcinomas from lung adenocarcinomas. The importance of searching for gene mutations to decide the treatment of PDTC.

68Ga-DOTA-peptide PET/CT for radiotherapy planning and evaluating treatment response in the management of meningiomas.

Meningiomas overexpress somatostatin receptors (SSTR). PET imaging with SSTR ligands such as 68Ga-DOTA-peptide has recently shown high diagnostic accuracy in identification of meningiomas due to lack of normal bone and brain activity. PET-derived parameters, especially gross tumour volume (GTV) delineation improves inter-observer variability and appears to be particularly promising for RT planning. The potential strength of 68Ga-DOTA in the ongoing assessment of treatment response and disease progression in meningioma, particularly in the post-surgical and post-radiation settings is encouraging. More prospective randomized studies with large cohorts of patients are required to define the effective role of this modality.

Demographic variables of Vestibular schwannoma's patients presented in Radio Surgical out- patient department of Cyberknife Robotic Radiosurgery, JPMC Karachi.

OBJECTIVE: To determine the age, gender and sites of vestibular schwannoma cases using contrast-enhanced magnetic resonance imaging. METHOD: The retrospective descriptive study was conducted at the Department of Cyberknife Robotic Radiosurgery, Jinnah Postgraduate Medical Centre, Karachi, and comprised data of patients with vestibular schwannomas from January 2016 to September 2018. Some of them were histologically proven and rest were radiologically proven. Cases were reviewed on contrast-enhanced magnetic resonance imaging of the brain. Statistical Package for the Social Sciences version 20 (SPSS) was applied. RESULTS: Of the 500 cases of vestibular schwannomas identified with 515 tumours, 300(60%) were males and 200(40%) were female. The overall mean age was 42.7±14.4 years (range: 17-85 years). Out of 515 tumours, the commonest site was the right cerebellopontine angle in 340(66%) cases. There were 15(3%) cases of radiologically-proven neurofibromatosis type 2. Overall, 490(98%) patients had main clinical complaint of progressive unilateral hearing loss, 5(1%) had vertigo and 5(1%) had facial palsy. CONCLUSIONS: Vestibular schwannomas were found to be more common among adults, with male preponderance and right cerebellopontine angle being the common site.