Efficacy and Safety of Trans-Arterial Yttrium-90 Radioembolization in Patients with Unresectable Liver-Dominant Metastatic or Primary Hepatic Soft Tissue Sarcomas

Patients with liver-dominant metastatic or primary hepatic soft tissue sarcomas (STS) have poor prognosis. Surgery can prolong survival, but most patients are not surgical candidates, and treatment response is limited with systemic chemotherapy. Liver-directed therapies have been increasingly employed in this setting, and Yttrium-90 trans-arterial radioembolization (TARE) is an understudied yet promising treatment option. This is a retrospective analysis of 35 patients with metastatic or primary hepatic STS who underwent TARE at a single institution between 2006 and 2020. The primary outcomes that were measured were overall survival (OS), liver progression-free survival (LPFS), and radiologic tumor response. Clinical and biochemical toxicities were assessed 3 months after the procedure. Median OS was 20 months (95% CI: 13.9–26.1 months), while median LPFS was 9 months (95% CI: 6.2–11.8 months). The objective response rate was 56.7%, and the disease control rate was 80.0% by mRECIST at 3 months. The following correlated with better OS post-TARE: liver disease control (DC) at 6 months (median OS: 40 vs. 17 months, p = 0.007); LPFS ≥ 9 months (median OS: 50 vs. 8 months, p < 0.0001); ECOG status 0–1 vs. 2 (median OS: 22 vs. 6 months, p = 0.042); CTP class A vs. B (median OS: 22 vs. 6 months, p = 0.018); and TACE post-progression (median OS: 99 vs. 16 months, p = 0.003). The absence of metastases at diagnosis was correlated with higher median LPFS (7 vs. 1 months, p = 0.036). Two grade 4 (5.7%) and ten grade 3 (28.6%) laboratory toxicities were identified at 3 months. There was one case of radioembolization-induced liver disease and two cases of radiation-induced peptic ulcer disease. We concluded that TARE could be an effective and safe treatment option for patients with metastatic or primary hepatic STS with good tumor response rates, low incidence of severe toxicity, and longer survival in patients with liver disease control post-TARE.

Advances in Y-90 radioembolization for the treatment of hepatocellular carcinoma

Hepatocellular carcinoma remains a prominent cause of cancer-related mortality globally. Transarterial yttrium-90 radioembolization is a versatile therapy and plays an important role in the treatment of hepatocellular carcinoma. This review summarizes the establishment of radioembolization in the hepatocellular carcinoma treatment paradigm, treatment considerations across cancer stages, and recent advances in evidence.

Frozen Hybrid Kernelised Expectation Maximisation For Bremsstrahlung SPECT Reconstruction

Background: Selective internal radiation therapy with Yttrium-90 microspheres is an effective therapy for liver cancer and liver metastases. Yttrium-90 is mainly a high-energy beta particle emitter. These beta particles emit Bremsstrahlung radiation during their interaction with tissue making post-therapy imaging of the radioactivity distribution feasible. Nevertheless, image quality and quantification is difficult due to the continuous energy spectrum which makes resolution modelling, and attenuation and scatter estimation challenging. Methods: In this study, a modified hybrid kernelised expectation maximisation is used to improve resolution and contrast and reduce noise. The iterative part of the kernel was frozen at the 72nd sub-iteration to avoid over-fitting of noise and background. A NEMA phantom with spherical inserts was used for the optimisation and validation of the algorithm, and data from 5 patients treated with Selective internal radiation therapy were used as proof of clinical relevance of the method. Results: The results suggest a maximum improvement of 56% for region of interest mean recovery coefficient at fixed coefficient of variation and better identification of the hot volumes in the NEMA phantom. Similar improvements were achieved with patient data, showing 47% mean value improvement over the gold standard used in hospitals. Conclusions: Such quantitative improvements could facilitate improved dosimetry calculations with SPECT when treating patients with Selective internal radiation therapy, as well as provide a more visible position of the cancerous lesions in the liver.

Case Report: Vasculitis Triggered by SIRT in a Patient With Previously Untreated Cholangiocarcinoma

Arising from the biliary tract, cholangiocarcinoma is a rare and aggressive epithelial cancer. According to the primary site, it can be further classified into intrahepatic, perihilar and distal types. Due to the lack of symptoms early in the disease course, most patients are diagnosed at advanced stages. Being not candidates for curative surgical management, these patients are treated with palliative systemic chemotherapy, and their prognosis remains poor. Using radioisotopes like yttrium-90 -labeled microspheres (90Y), radioembolization represents a local approach to treat primary and secondary liver tumors. In the case of intrahepatic cholangiocarcinoma, radioembolization can be used as a primary treatment, as an adjunct to chemotherapy or after failing chemotherapy. An 88-year-old man underwent radioembolization for a previously untreated stage II intrahepatic cholangiocarcinoma. One week later, he presented to our clinic with a non-pruritic maculopapular rash of the lower extremities and abdomen, worsening fatigue and low-grade fever. Laboratory exams, including hepatitis screening, were within normal limits. Showing positive immunofluorescence staining for immunoglobulin M (IgM) and complement 3 (C3) in vessel walls without IgA involvement, the skin biopsy results were compatible with leukocytoclastic vasculitis. Apart from the anticancer intervention, there have been no recent medication changes which could explain this complication. Notably, we did not observe any side effects during or after the perfusion scan with technetium-99m macroaggregated albumin (MAA) performed prior to radioembolization. The symptoms resolved quickly after a short course of colchicine and did not reappear at cholangiocarcinoma progression. In the absence of other evident causes, we conclude that the onset of leukocytoclastic vasculitis in our patient was directly linked to the administration of yttrium-90 -labeled microspheres. Our report therefore demonstrates that this condition can be a rare but manageable complication of 90Y liver radioembolization.

Yttrium-90 Internal Radiation Therapy as Part of the Multimodality Treatment of Metastatic Colorectal Carcinoma

About 70% of patients with metastatic colorectal carcinoma (mCRC) have liver metastases. Hepatic failure accounts for most mCRC-related deaths. Therefore, controlling liver metastases may improve outcomes. A data overview of liver-directed treatment using yttrium-90 selective internal radiation therapy (SIRT) is provided as part of a multimodality treatment. SIRT in mCRC is discussed, and the prognostic factors for patient selection are defined. Pooled analyses of three recent trials incorporating SIRT plus chemotherapy revealed subsets of patients with mCRC who might benefit from SIRT. A multidisciplinary treatment for most mCRC patients is proposed to achieve long-term survival in this cohort of patients.