Aaron Jessop

The prognostic value of interim positron emission tomography scan in patients with classical Hodgkin lymphoma

The prognostic value of interim positron emission tomography (PET) was evaluated after 2 cycles of doxorubicin, bleomycin, vinblastin and dacarbazine in classical Hodgkin lymphoma patients (n = 229), based on Deauville criteria. In early stage non‐bulky disease, bulky stage II disease, advanced stage low International Prognostic Score (IPS ≤2) and advanced stage (IPS ≥3), 3‐year progression‐free survival rates in PET2‐negative vs. PET2‐positive groups were 95·9% vs. 76·9% (P < 0·0018), 83·3% vs. 20·0% (P = 0·017), 77·0% vs. 30·0% (P < 0·001) and 71·0% vs. 44·4%(P = 0·155), respectively. The outcome after positive PET2 was better than previously reported. The results from non‐randomized studies of PET2‐guided therapy would be valuable with careful interpretation.

Qualitative and quantitative comparison of gated blood pool single photon emission computed tomography using low-energy high-resolution and SMARTZOOM collimation.

Objective The aim of this study was to assess the feasibility of IQ-SPECT gated blood pool (MUGA) under conditions of decreased scan time (ST). Patients and methods Ten patients underwent routine 26-min, two-view planar, followed by LEHR and IQ-SPECT MUGA, on a Siemens dual-head Symbia scanner. Six ‘back and forth’ 4-min SPECT scans were summed into 4-, 8-, 12-, 16-, 20-, and 24-min equivalent scans, and reconstructed iteratively (IQ-SPECT and LEHR) and with FBP (LEHR). Uniformity, contrast, and wall motion were scored on a five-point scale. Linear regressions of left ventricular (LV) ejection fraction (EF) were performed between FBP, Flash 3D, and IQ-SPECT versus planar and Flash 3D and IQ-SPECT versus FBP. Agreement tables between Flash 3D and IQ-SPECT versus FBP LV EF were generated using a normal versus cardiotoxicity threshold of 50%. Results IQ-SPECT had the best scores for all STs, and 4, 8, and 16 min IQ-SPECT were judged to be similar to 24-min LEHR FBP, Flash 3D, and planar, respectively. The average LV EF correlation coefficients were 0.69, 0.71, and 0.63 between IQ-SPECT, Flash 3D, and FBP versus planar, respectively; 0.70 between IQ-SPECT and FBP; and 0.88 between Flash 3D and FBP, and all were statistically significant (P<0.05), except for 16-min FBP LEHR versus planar. Agreement tables showed diagnostic equivalence of IQ-SPECT, Flash 3D, and FBP. Conclusion These preliminary results suggest that IQ-SPECT is equivalent to LEHR Flash 3D and FBP for MUGA SPECT, and better at reduced ST. A larger patient population study is necessary for a more definitive assessment.

Cross sectional and nuclear medicine imaging of pancreatic insulinomas

Insulinomas are rare neuroendocrine tumors which occur predominantly in the pancreas. Although majority of the insulinomas are benign, over-secretion of insulin by the tumor leads to debilitating hypoglycemic symptoms. The diagnosis is based on clinical and biochemical findings. After the diagnosis is made, the principal challenge lies in locating the tumor because most tumors are solitary and small in size. Locating the tumor is of paramount importance as complete surgical excision is the only curative treatment, and incomplete resection leads to persistence of symptoms. Different preoperative and intraoperative imaging techniques have been used with varying success rates for the insulinoma imaging. Besides localizing the tumor, imaging also helps to guide biopsy, detect metastatic lesions, and perform image-guided therapeutic procedures. This review will discuss the role of different Cross sectional and nuclear medicine imaging modalities in insulinomas.

Management of Locally Advanced and Metastatic Pheochromocytoma and Paraganglioma

Malignant pheochromocytoma and malignant paraganglioma are diagnosed when metastases are present. These rare tumors have a variable clinical presentation and there are no clear pathological factors predictive of metastasis. However, a primary tumor size larger than 5 cm, succinate dehydrogenase B (SDHB) mutations, or extra-adrenal location are clinical predictors of metastatic disease. Patients with these factors at the initial presentation should have close lifelong follow-up with metanephrines and imaging. Metastatic pheochromocytoma and paraganglioma are associated with a genetic germline mutation in up to 50 % of cases. The most common genetic alteration is a mutation of the SDHB gene. Today, advanced genetic test such as next-generation sequencing with a panel to detect all mutations associated with this neuroendocrine tumor is possible. It is suggested that any patient with a pheochromocytoma and/or paraganglioma should be given the opportunity for genetic testing. Malignant pheochromocytoma and paraganglioma patients should have genetic counseling in order to clarify patient’s expectations and decide when to perform a genetic evaluation. Patients with metastatic disease may be classified according to type of metastasis and the burden of the disease. Patients with synchronous disease and high tumor burden have worse prognosis. Once metastatic disease is present there are several management options including observation and systemic therapies with chemotherapy, molecular targeted therapies, or radiopharmaceutical agents such us 131I metaiodobenzylguanidine (MIBG) therapy.