Evaluation of treatment response by Hopkins criteria on 18 F FDG PET-CT in patients of non-small cell lung cancer and its comparison with PERCIST response criteria.

AIM: To assess treatment response on FDG PET-CT in NSCLC patients by visual Hopkins score compared to PERCIST criteria and its potential for prognostication (or its correlation with survival). METHODS: Forty-four NSCLC patients with baseline and post-treatment FDG PET-CT scans were included, and interpreted using Hopkins and PERCIST criteria classifying patients into responders and non-responders. PERCIST-based CMR and PMR, and Hopkins Scores 1,2,3 were classified responders. PERCIST-based SD and PD and Hopkins scores 4,5 were classified as non-responders. Patients were followed upto 24 months after treatment completion. Cohen kappa for inter-criteria agreement and Kaplan Meir curve for overall survival (OS) analysis done. RESULTS: Out of 44 patients, PERCIST classified 27 (61.3%) as responders and 17 (38.6%) as non-responders, whereas Hopkins classified 12 patients (27.3%) as responders and 32 (72.7%) as non-responders. Inter-criteria agreement was low (kappa=0.19) with discordance in 45.5% of patients. Eighteen of 20 discordant cases were non-responders on Hopkins and responders on PERCIST, of which 88.8% were non-responders on follow-up as predicted by Hopkins. PERCIST responders had OS of 96.4% and 64.3% at 9 and 24 months, respectively, while non-responders OS was 93.5% and 40.2% at 9 and 24 months, respectively ( P -value = 0.049). However, responders on Hopkins had OS of 100% at 24 months, whereas non-responders had OS of 93.5% and 51.5% at 9 and 24 months, respectively ( P -value = 0.232). CONCLUSION: Semi-quantitative PERCIST and visual Hopkins criteria show low inter-criteria agreement, with visual criteria better-predicting survival in patients of NSCLC.

18 F-FDG PET-CT Evaluation of Primary Adrenal Ewing Sarcoma with Venous Thrombosis: An Unusual Presentation.

Ewing sarcoma (EWS) is primarily an osseous malignancy of childhood and young adults. Extraskeletal occurrence is less frequent and primary adrenal involvement is an even rare presentation. We present such a case of a 7-year-old boy diagnosed with adrenal EWS with associated venous thrombosis and pulmonary embolism detected on 18 F-fluorodeoxyglucose positron emission tomography-computed tomography scan.

Mimicker of Osteoblastic Skeletal Metastasis on 18 F-FDG PET/CT Scan in a Case of Primary Mediastinal Germ Cell Tumor.

ABSTRACT: Primary mediastinal germ cell tumors are uncommon tumors, of which the nonseminomatous type is more likely to metastasize than the seminomatous type. Primary mediastinal germ cell tumors may also present with superior vena cava obstruction. Here, we present this case of primary mediastinal germ cell tumor with superior vena cava obstruction causing dilatation of collaterals in dorsal intravertebral venous plexus, which strongly mimics sclerotic skeletal lesions/metastasis on a Contrast-enhanced CT scan and also appears FDG avid on PET scan. Herein, we can differentiate the two by just a simple review of plain CT scan image.

Incidental Detection of Mandibular Metastasis in Renal Cell Carcinoma on 99mTc-MIBI Scan.

ABSTRACT: MIBI scintigraphy is the most widely used modality to identify parathyroid adenomas preoperatively. However, MIBI is also known to accumulate in multiple benign and malignant lesions. In renal cell carcinoma, 30% of the patients present with distant metastasis, commonly lungs and bone; however, jaw bone metastases are extremely rare (<1% of oral malignancies). Here we present a rare case of MIBI-avid mandibular metastasis in bilateral renal cell carcinoma on 99mTc-MIBI scintigraphy. Thus, we emphasize on careful interpretation of 99mTc-MIBI scans, which in addition to parathyroid adenomas can incidentally detect concurrent malignant lesions.

Role of 18F-Fluorodeoxyglucose Positron Emission Tomography-Contrast-Enhanced Computed Tomography in Detection of Early Recurrence with Peritoneal Disease in a Case of Adrenocortical Carcinoma.

Adrenocortical carcinoma (ACC) is an uncommon and highly aggressive malignancy with a poor prognosis. Common sites of metastasis are lung, liver, and lymph nodes. We present a case of ACC in a 54-year-old female with an early disease recurrence of unusual hypervascular peritoneal metastatic abdominal-pelvic deposits detected on 18F-fluorodeoxyglucose positron emission tomography-contrast-enhanced computed tomography scan.

An Unusual Case of Urothelial Carcinoma of Bladder with Metastasis to Brain and Skeletal Muscles Evaluated on 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography.

Urothelial or transitional cell carcinoma is the most prevalent variant of urinary bladder carcinoma worldwide occurring in both men and women. There are a very few cases described in the literature with metastasis to skeletal muscles and even fewer cases with metastatic site in the brain. We present a case of high-grade urothelial carcinoma with metastasis to the left temporal lobe as well as multiple inter- and intra-muscular deposits in the left thigh.

An Unusual Case of Bilateral Ureteric Metastasis on PSMA PET-CT Scan in Carcinoma Prostate.

ABSTRACT: The most common locations for metastasis in adenocarcinoma of the prostate gland are lymph nodes, bone, lung, and liver. The involvement of the ureter as a site of metastasis in prostate carcinoma is quite rare in literature. Here we present a case involving bilateral ureters along with bilateral vesicoureteric junctions in a known case of prostate adenocarcinoma.

Pazopanib-Induced Asymptomatic Necrotizing Pancreatitis Diagnosed on 18F-FDG PET-CT Scan.

Multi-targeted tyrosine kinase inhibitor (TKI) pazopanib approved for the treatment of advanced soft tissue sarcoma (STS) has prolonged the estimated survival times and quality of life of patients. However, several adverse effects associated predominantly with the inhibition of the vascular endothelial growth factor receptor by these drugs may prove to be potentially life-threatening. One such rare adverse event with the use of pazopanib is acute pancreatitis. We present a case of asymptomatic necrotizing pancreatitis induced by pazopanib treatment for metastatic STS detected on 18F-FDG PET-CT imaging.

Unusual Asymptomatic Fluorodeoxyglucose Avid Pheochromocytoma in a Case of Myxoid Liposarcoma of the Extremity on 18-F Fluorodeoxyglucose Positron Emission Tomography-computed Tomography.

Sarcomas are a heterogeneous group of rare tumors and arise either from soft tissue or from bone. Soft-tissue sarcomas (STSs) initially metastasize to the lungs. Metastases to extrapulmonary sites such as liver, brain, and soft tissue distant from primary tumor usually develop later. However, cases with isolated adrenal metastasis without disseminated disease have been reported in literature. We present a case of primary myxoid liposarcoma of the lower limb, in which staging 18-F fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) scan detected a suspicious FDG avid adrenal lesion which eventually on resection was diagnosed as asymptomatic pheochromocytoma. Pheochromocytomas have been reported to demonstrate FDG uptake mimicking metastasis. Hence, while interpreting FDG PET-CT scans in the context of STSs, both the extrapulmonary metastatic potential of aggressive histological subtypes of sarcoma and rare possibility of FDG avid coexistent benign tumor should be taken into consideration.

Unusual case of infantile fibrosarcoma evaluated on F-18 fluorodeoxyglucose positron emission tomography-computed tomography.

Infantile fibrosarcoma (IFS) is a rare soft-tissue sarcoma originating from extremities and occasionally from axial soft tissue. The prognosis is good with favorable long-term survival. It is rarely metastasizing tumor, the chances being lesser with IFS originating from extremities. Use of neoadjuvant chemotherapy (NACT) as a treatment regime further reduces the chances of local relapse and distant metastasis. The organs commonly affected in metastatic IFS are lungs and lymph nodes. We report an unusual case of an IFS originating from extremity, which received NACT, yet presented with an early metastatic disease involving soft tissues and sparing lungs and lymph nodes, as demonstrated on fluorodeoxyglucose positron emission tomography-computed tomography.

Rare case of primary inferior vena cava leiomyosarcoma on F-18 fluorodeoxyglucose positron emission tomography-computed tomography scan: Differentiation from nontumor thrombus in a background of procoagulant state.

We report a rare case of leiomyosarcoma of the inferior vena cava (IVC) in which F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography-computed tomography (PET-CT) scan provided vital evidence, which led to its diagnosis, in a background of procoagulant state of the patient, where previous ultrasound-Doppler and echocardiography studies were nonspecific and revealed bilateral lower limb deep vein thrombosis with thrombus in IVC. The whole body F-18 FDG PET-CT scan was done in view of no significant improvement in clinical status of the patient over few months in spite of appropriate medical management. FDG PET-CT scan revealed high grade uptake in a large mass lesion occupying the right atrium, extending superiorly into terminal superior vena cava, inferiorly into dilated IVC and probably into hepatic veins. CT guided biopsy of this F-18 FDG avid mass was consistent with the diagnosis of leiomyosarcoma, which however was not amenable to surgery at this stage. F-18 FDG PET-CT accurately differentiated tumor mass from bland thrombus and further had a significant impact on the management, since aggressive surgery combined with adjuvant therapy offers the best outcome for patients with leiomyosarcoma of the IVC.