Liver radioembolization : from dosimetry to clinical effects

Selective internal radiation therapy (SIRT) is part of the treatment strategy of liver tumors. SIRT can be performed using resin or glass microspheres, demonstrating different chemico-physical and radioactive properties. Post therapy imaging using 90Y PET/CT can evaluate the deposition of the tumor-absorbed dose and predict the patient outcome. 90Y PET/CT can also precisely evaluate the heterogeneous distribution of the absorbed dose within the tumor by calculating a equivalent uniform dose (EUD). Tumor EUD is strongly correlated with survival of patients and reunifies the absorbed doses between resin and glass microspheres as well as those from external radiation beam therapy. Moreover, pre-therapy imaging using 99mTc macroaggregated albumin (MAA) can optimize the activity planning, predicting with high accuracy the absorbed dose to the healthy liver. Furthermore, the tumor targeting can be optimized using a specific catheter during the arteriography, named antireflux catheter (ARC). Using ARC, the absorbed dose can be significantly increased in neuroendocrine and HCC tumors, hence, increasing the tumor control probability.(MED - Sciences médicales) -- UCL, 202

The Role of Quantitative and Semi-quantitative [F]FDG-PET/CT Indices for Evaluating Disease Activity and Management of Patients With Dermatomyositis and Polymyositis.

Idiopathic inflammatory myopathies (IIM) are considered systemic diseases involving different organs and some subtypes are associated with increased cancer risk. In this review, we provide a comprehensive summary of the current use and potential applications of (semi-)quantitative [F]FDG-PET/CT indices in patients with IIM focusing on dermatomyositis and polymyositis. Visual interpretation and (semi-)quantitative [F]FDG-PET indices have a good overall performance to detect muscle activity but objective, robust and standardized interpretation criteria are currently lacking. [F]FDG-PET/CT is a suitable modality to screen for malignancy in patients with myositis and may be a promising tool to detect inflammatory lung activity and to early identify patients with rapidly progressive lung disease. The latter remains to be determined in large, prospective comparative trials

Vertebral uptake of 99mTc-macroaggregated albumin during lung perfusion scanning

A 53-year-old female underwent a lung ventilation/perfusion scintigraphy (V/Q scan) in the workup of extensive thrombosis of the left subclavian and internal jugular veins. The perfusion lung scan visualized an atypical uptake in the thoracic vertebrae. A chest Computed Tomography (CT) scan demonstrated unusual tortuous and opacified thoracic superficial veins, collaterals of the lateral thoracic vein. Many venous collateral pathways can be developed in the case of superior vena cava syndrome. 99mTc-macroaggregated albumin particles may pass through the lateral thoracic vein and eventually through the vertebral venous plexus before being finally trapped by the vertebral capillaries. Besides right-to-left shunting, extrapulmonary uptake in the lung perfusion scintigraphy is very rare and may be used by collateral venous pathways

Hepatic Arterial Buffer Response in Liver Radioembolization and Potential Use for Improved Cancer Therapy.

Liver radioembolization is a treatment option for unresectable liver cancers, performed by infusion of Y or Ho loaded spheres in the hepatic artery. As tumoral cells are mainly perfused via the liver artery unlike hepatic lobules, a twofold tumor to normal liver dose ratio is commonly obtained. To improve tumoral cell killing while preserving lobules, co-infusion of arterial vasoconstrictor has been proposed but with limited success: the hepatic arterial buffer response (HABR) and hepatic vascular escape mechanism hamper the arterioles vasoconstriction. The proposed project aims to take benefit from the HABR by co-infusing a mesenteric arterial vasodilator: the portal flow enhancement inducing the vasoconstriction of the intra sinusoids arterioles barely impacts liver tumors that are mainly fed by novel and anarchic external arterioles. Animal studies were reviewed and dopexamine was identified as a promising safe candidate, reducing by four the hepatic lobules arterial flow. A clinical trial design is proposed. A four to sixfold improvement of the tumoral to normal tissue dose ratio is expected, pushing the therapy towards a real curative intention, especially in HCC where ultra-selective spheres delivery is often not possible

Successful treatment with yttrium-90 microspheres in a metastatic breast cancer patient and sclerosing cholangitis.

Breast cancer is the most common malignancy occurring in women worldwide. More than 90% of patients present with localized disease are treated with curative intent; however, recurrence can occur with development of metastatic lesions. Frequently associated with extra-hepatic lesions, localized treatments (surgery or stereotaxic body radiotherapy) are rarely proposed in liver lesions. Y radioembolization has extensively been evaluated in colorectal cancer, but its role in breast cancer with isolated liver metastases remains largely unknown. Pre-existing liver diseases are known risk factors for Y induced liver toxicity. Not considered as an excluding factor for this treatment, data are limited regarding its safe use with cholangitis. We report a successful control of liver metastases by Y radioembolization in a breast cancer patient

90Y TOF-PET based EUD reunifies patient survival prediction in resin and glass microspheres radioembolization of HCC tumours

Clinical studies reported a twofold ratio between the efficacies per Gy of resin versus glass spheres. Our aim is to investigate whether this difference could result from the different degrees of heterogeneity in sphere distribution between the two medical devices. The 90Y TOF-PET based equivalent uniform doses (EUD) was used for this purpose. 58 consecutive HCC radioembolizations were retrospectively analyzed. Absorbed doses D and Jones–Hoban EUD in lesions were computed. Radioembolization efficacy was assessed using Kaplan–Meier survival curves. In order to match together the glass and resin spheres survival curves using a 40 Gy-threshold, an efficacy factor of 0.73 and 0.36 has to be applied on their absorbed dose, respectively. Using EUD, a nice matching between glass and resin survival curves was obtained with a better separation of the responding and not responding survival curves. The results clearly support the fact that the activity heterogeneity observed in 90Y TOF-PET post radioembolization does not only result from statistical noise, but also reflects the actual heterogeneity of the spheres distribution. Use of EUD reunifies the efficacy of the two medical devices

Sorafenib Reduced Significantly Heptopulmonary Shunt in a Large Hepatocelullar Carcinoma

An 81-year-old man with a large hepatocellular carcinoma was referred in our institution for 90Y radioembolization (RE). The preliminary arteriography using 99mTc-macroaggregate albumin demonstrated an important hepatopulmonary shunt. It was an exclusion criterion for RE due to high risks of lung radiations. Then, the patient was treated with sorafenib during 4 months, stopped because of grade 3 toxicity. A second liver arteriography was performed, and 99mTc-macroaggregate albumin imaging showed an important reduction of the lung shunt. Transient therapy with sorafenib permitted to close the lung shunt and was a bridge for RE

Hibernoma mimicking liposarcoma

A 26-year-old man was referred to the ophthalmology department with a 1-week history of blurred vision of the left eye; there was no pain or redness. Ophthalmological examination found unilateral choriocapillaropathy with optic nerve oedema. He was in a stable relationship and had not travelled abroad recently, nor had he been in contact with any animals or pets. He had a history of ulcerative colitis diagnosed 2 years earlier for which he was treated for 1 year with azathioprine and oral corticosteroids. Since then he had been totally asymptomatic. [...

Hibernoma mimicking liposarcoma

A 26-year-old man was referred to the ophthalmology department with a 1-week history of blurred vision of the left eye; there was no pain or redness. Ophthalmological examination found unilateral choriocapillaropathy with optic nerve oedema. He was in a stable relationship and had not travelled abroad recently, nor had he been in contact with any animals or pets. He had a history of ulcerative colitis diagnosed 2 years earlier for which he was treated for 1 year with azathioprine and oral corticosteroids. Since then he had been totally asymptomatic. [...