Treatment of hepatocellular carcinomas by thermal ablation and hepatic transarterial chemoembolization

Abstract

Local tumor recurrence after thermal ablation of hepatocellular carcinoma (HCC) can impact on overall survival and are very closely linked to partial treatment of the primary lesion or to potential microvascular invasion or satellite micronodules located close to the main lesion. The diagnosis of these liver metastases close to the primary lesion on CT and MRI is difficult and their incidence, number and spread throughout the liver correlates with diameter of primary tumor. Tumor diameter is currently the key factor to predict whether or not thermal ablation of HCC will be complete or not. It has now been shown for monopolar radiofrequency ablation that this therapy alone is sufficient to effectively treat single HCCs<3cm in diameter provided that liver micrometastases are not present. If the HCC is>3cm in size, multifocal or in the case of tumor recurrence, overall survival and recurrence-free survival results are better if monopolar radiofrequency ablation is combined with hepatic trans-arterial chemoembolization. The timing of this combination of treatments probably influences its effectiveness on tumor and tolerability and remains to be assessed.

Survival analysis of 230 patients with unresectable hepatocellular carcinoma treated with bland transarterial embolization

“…This trend is also confirmed in our TAE study, where PT predicted a better OS increasing the chance of survival by 37%. PT is normally proposed for BCLC 0-A stage HCCs when less than three nodules under 3 cm in size are present [35], but an efficacious TAE may be used to downstage the disease and allow for PT, as occurred in 16% of our patients. There are limitations to this retrospective survival analysis.…”

Needle Tract Seeding after Percutaneous Cryoablation of a Metastatic Hepatic Tumor from Renal Cell Carcinoma: A Case Report

“…In the current case, the lack of administration of an anti-cancer drug and the 1-week interval between the two procedures may have reduced the cell-killing and blood flow-blocking effects. Regarding the combination treatment interval, thermal ablation is rarely delivered on the same day as or on the day after TAE, but instead, is usually administered 2-4 weeks later [11]. In addition, ablative margins were significantly higher when RFA after TAE was performed until 4 weeks compared to RFA alone [12].…”

Ablation plus Transarterial Embolic Therapy for Hepatocellular Carcinoma Larger than 3 cm: Science, Evidence, and Future Directions

“…10,11 Factors mitigating the efficacy of thermal ablation monotherapy for large tumors include reduced thermal insult from increased tissue perfusion, known as the heat sink effect, and increased propensity for satellite formation outside of the treatment margin. 4,12 TAE and TACE induce ischemic tumor necrosis by selective reduction of hepatic arterial perfusion to tumor and offer synergistic effects with thermal ablation. In an animal model, RFA prior to TACE did not significantly increase volume of necrosis versus RFA alone; however, there was increased distribution of chemotherapeutic agents to the tumor periphery.…”

“…[1][2][3] This is felt to be a function of both the technical limitations of safely ablating larger tumors and the increased need for margin. 4 Tumor size is associated with an increased risk for recurrence due to the propensity for microvascular invasion present in 25% of tumors under 3 cm and 55% of lesions over 6.5 cm and satellites occurring in 16.7 to 27.2% of tumors under 3 cm and 72% of over 8.0 cm. 4 Transarterial embolic therapies including bland transarterial embolization (TAE) and transarterial chemoembolization (TACE) in combination with ablative modalities have been shown to improve outcomes in animal models and clinical studies and have increased the size of tumors that can be treated with curative intent.…”

“…4 Tumor size is associated with an increased risk for recurrence due to the propensity for microvascular invasion present in 25% of tumors under 3 cm and 55% of lesions over 6.5 cm and satellites occurring in 16.7 to 27.2% of tumors under 3 cm and 72% of over 8.0 cm. 4 Transarterial embolic therapies including bland transarterial embolization (TAE) and transarterial chemoembolization (TACE) in combination with ablative modalities have been shown to improve outcomes in animal models and clinical studies and have increased the size of tumors that can be treated with curative intent. 5,6 TACE of solitary tumors 2 cm has inferior outcomes compared with ablation, 7 suggesting that the benefit of combination therapy is a function of therapeutic synergy rather than the addition of TACE alone.…”