The Barcelona clinic liver cancer guidelines (
2) and the Japan society of hepatology guidelines (
3) use a liver function C-P class A or B as the criterion to determine the most suitable HCC treatment. Therapeutic options for HCC include surgical resection, radiofrequency ablation, TACE, and sorafenib administration. However, no established evidence-based treatment is currently available for patients with C-P class B liver function, for whom these treatments cannot be administered or are not expected to be effective. Therefore, the development of treatments for this specific patient group is essential. In Japan, HAIC is often used to treat HCC in these patients. However, the clinical usefulness of HAIC remains undetermined, with little data available for patients having poor liver function.
In our study, we retrospectively analyzed treatment outcomes of HAIC with cisplatin in cisplatin-naïve patients with HCC and C-P score ≥ 8 who were considered TACE-refractory or -ineligible, with the aim of determining the safety and usefulness of this treatment regimen. Our review of relevant research identified scant information regarding the safety and efficacy of HAIC for the treatment of HCC in patients classified with poor liver function (C-P class B). The only study on this subject has been conducted by Miyaki et al. (
15) evaluating the treatment outcome as a function of C-P score.
In our study, the MST for the study group, overall, was 186 days (6.2 months), which was longer than the 3.9-month MST reported by Miyaki et al., although these two values cannot be directly compared due to differences in the characteristics of the patient group between these two studies. Moreover, the MST in MVI- negative cases and those without extrahepatic spread of the disease was 341 days (11.3 months), which was better than the 10.2 and 8.0 months of MST reported for the placebo groups in the Sorafenib hepatocellular carcinoma assessment randomized protocol (SHARP) trial and the Asia-Pacific study (
5), respectively, which were conducted on C–P class A patients. Our finding supports the clinical usefulness of HAIC with cisplatin for patients with C-P score ≥ 8 who are considered TACE-refractory or -ineligible. On the other hand, the response and disease control rates reported by Miyaki et al. (
15) were superior to our rates: response rate, 13.5% vs. 10.7%, respectively; disease control rate, 40.5% vs. 35.7%, respectively. In addition to the characteristics of the study group in Miyaki et al. and our study as a reason for the discrepancy, differences in outcomes can also be related to differences in treatment regimen. Miyaki et al. discussed the possibility that hepatic disorders in their study may have been adversely affected by their 5-fluorouracil treatment, with treatment-related failure in hepatic function identified in 27.7% of their patients. In our regimen, we used cisplatin fine powder as anti-cancer drug, with liver function-related adverse events of the regimen identified in 10% to 15% of the patients. However, these adverse events were usually transient and did not progressive to a severe state. Therefore, for TACE-refractory or -ineligible HCC patients with a C-P score ≥ 8, HAIC with cisplatin can be performed with little influence on hepatic function while improving overall prognosis.
With regard to the relationship between dose reduction and treatment efficacy, we identified a comparable rate of disease control among patients who received the full dose of cisplatin and those who received a reduced dose. This is an important finding when we consider that the full dose of cisplatin was associated with a higher incidence of adverse events. Therefore, as our study provides evidence of a survival benefit and disease control of HAIC with cisplatin which was comparable for full and reduced doses, as confirmed using the RECIST criteria, a reasonable approach would be established to provide a reduced dose of cisplatin, as indicated for a patient. The positive effect of a full dose of cisplatin in increasing BW is likely to have been influenced by the increased hydration provided by the larger quantity of intravenous infusion used for patients receiving a full dose to prevent cisplatin-associated renal damage.
Finally, among the 28 patients forming out study group, 9 MVI-negative cases were considered to be ineligible for TACE due to concerns about postoperative liver failure that could result in death or deterioration in quality of life. Recently, Bolondi and colleagues have proposed a sub-classification and revision of treatment strategies for intermediate stage (BCLC B) HCC because it represents an extremely heterogeneous population (
16). According to their study, TACE is not recommended for patients with Child-Pugh score of 8 or 9 points because TACE would be likely to precipitate liver dysfunction. It seems that their concept supports the idea of our study that intermediate stage HCC with C-P score ≥ 8 was considered TACE-ineligible from the view point of hepatic toxicity. However, recently, TACE using drug-eluting microspheres has been developed, with emerging evidence of its relatively higher safety and effectiveness compared to conventional TACE with lipiodol in patients with bilobar, C-P B, and HCC (
17). Therefore, TACE with microspheres for multiple HCCs may be beneficial, especially in cases with a C-P score of 8. However, it has also been reported that the prognosis of HCC patients with a selection for TrAnsarterial chemoembolization TrEatment (STATE) score < 18 is very poor (
18). In our study, all 2 patients with a C-P score of 8 and 3 out of 6 patients with a C-P score of 9, who were MVI-negative and had no prior history of TACE, had STATE scores of < 18. Therefore, a better prognosis after TACE cannot necessarily be expected in many cases of this examination. Such cases would in fact commonly be treated with HAIC in practice due to concerns of hepatic failure leading to deterioration of quality of life or death after TACE.
Some limitations to this study need to be acknowledged when interpreting our study results. These limitations include a small sample size, retrospective design, clinical population selected from a single center, ambiguous criteria for dose reduction and discontinuation, possible selection bias, and unknown validity of the clinical judgment relating to TACE non-response or ineligibility. To resolve these issues, a multi-center prospective study should be conducted in future.
4.1. Conclusion
HAIC with cisplatin can be performed safely and appears to be clinically useful in patients with HCC and C-P score ≥ 8 who are considered TACE-refractory or -ineligible.