迄今为止，肝移植应该是治疗肝癌的最佳方法，因为肝移植可以同时处理和解决肿瘤和肝脏疾病。Mazzaferro提出的了肝移植术的适应标准。这一标准是根据以往肝移植的效果所得出的。即单个肿瘤，直径≤5cm，或瘤灶数目≤3个，每个直径≤3cm，按此标准筛选，Mazzaferro报道了高达75%的4年生存率。Yao提出的UCSF标准放宽了Milan标准，建议肝移植适应征为：单个肿瘤，直径≤6.5cm或瘤灶数目≤3个，每个直径≤4.5cm，且直径合计≤8cm。现在学术界的争议是：（1）肝移植的适应标准是否应该进一步放宽；（２）Child A级肝功能的患者是否应该接受肝移植；（３）活体肝移植（LDLT）与接受尸体供肝移植（DDLT）的效果是否相同。在尸体供肝有限的国家，肝移植并不是可切除的肝细胞癌的第一治疗选择。在中亚地区，对可以进行移植的肝癌病例（肝功能Child A级）采取肝移植治疗与肝部分切除术的效果没有明显区别。随着活体肝移植的广泛开展，越来越多超过Milan标准的肝癌患者接受了肝移植。在日本京都，早期的结果（4年存活率为60%）还是令人满意的。而且针对这部分不能接受手术的肝癌患者，接受肝移植后的生存率也要明显高于其它治疗方法。在香港大学医学中心，我们同时开展活体肝移植（LDLT）和接受尸体供肝移植（DDLT）。LDLT的远期效果似乎比DDLT要差。我想这里有多方面的原因。接受DDLT的患者往往是具有某种特征的，就是说只有患者身上的癌细胞的生长速度相对缓慢，才有可能等到死者捐献肝脏。还有，就是LDLT的移植体比较小。部分肝移植手术的创伤以及肝细胞旺盛的再生能力都是加速癌细胞生长的因素。研究人员应该开展进一步的研究，以减少部分肝移植手术的创伤，从而降低肝癌复发的可能性。
Liver transplantation for HCC
SHEUNG-TAT FAN
Department of Surgery, The University of Hong Kong, Pokfulam, Hong Kong, China.
Liver transplantation should be the best treatment for HCC because both the tumor and the underlying liver diseases are treated simultaneously. The indication was well-defined by Mazzaferro. The criteria of the selection were based on the outcome of liver transplantation. Patients with solitary HCC less than 5cm or fewer than 3 in number, each less than 3cm had a 4-year survival rate of 75%. Recently, the criteria of selection have been extended slightly by Yao. The UCSF criteria consisted of solitary tumor ? 6.5cm, or 3 or fewer nodules with the largest lesion ? 4.5cm and the total tumor diameter ? 8cm. The current controversies are 1) whether the criteria of selection could be further relaxed; 2) whether the Child’s A liver function patients should receive liver transplantation; and 3) whether the outcome of live donor liver transplantation (LDLT) is the same as deceased donor liver transplantation (DDLT). In countries where deceased donor grafts are limited, as long as the HCC is resectable, liver transplantation is not the first choice. In Asian centers, the outcome of patients with transplantable HCC (and Child A liver function) having partial hepatectomy is about equal to those series in which liver transplantation is performed. With the wide application of LDLT, more and more liver transplantations were performed in patients with HCC beyond the Milan criteria. In Kyoto, the early result (4-year survival rate of 60%) appears satisfactory and is better than any treatment for patients with inoperable HCC. In our center, we perform LDLT and DDLT for HCC patients. The long-term outcome of LDLT is worse than that of DDLT. There are many reasons for the differences. Patients receiving DDLT are those naturally selected, i.e. only patients with slowing growing HCC could survive long enough to receive deceased donor grafts. Other reasons may be related to the small graft size in LDLT. Small-for-size graft injury and rapid liver regeneration may set up a favorable background for rapid HCC growth. Further research will target at reducing small-for-size graft injury to reduce HCC recurrence.
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