Sporn J R
Division of Hematology-Oncology, University of Connecticut Health Center, Farmington 06030-1315, USA.
Drugs. 1999 Jan;57(1):69-79. doi: 10.2165/00003495-199957010-00006.
Pancreatic cancer is widely regarded by medical personnel and the lay public as one of the most dreaded of all diagnoses. Although in selected series of operable patients the chance of long term survival may reach 20%, most patients have unfavourable disease at the time of diagnosis, and for the entire group of newly diagnosed patients, 5-year survival is rare. This grim outlook results from a combination of factors, including an anatomical location which makes early detection by screening tests or by symptoms difficult, a high tendency for spread to regional lymphatics and the liver, a poor profile of sensitivity to chemotherapeutic agents and the poor medical condition of many patients at the time of diagnosis. These factors mean that it is particularly important that at the time of diagnosis these patients are carefully evaluated, and that they and their families are fully aware of the treatment options available to them and the associated potential risks and benefits. For localised cancers, surgical resection alone offers the potential for long term survival. The addition of postoperative radiation therapy (RT) predictably improves local control but has minimal impact on survival, which is primarily determined by the development of liver metastases. Randomised trial data support the use of combined fluorouracil (5-FU) chemotherapy and RT in patients who have undergone pancreatectomy and have negative margins, although the benefits are modest and the relevant randomised trials enrolled relatively small patient numbers. For patients with marginally resectable tumours, the feasibility has been demonstrated of using chemotherapy plus RT to reduce tumour size before resection, but it is unclear whether this approach will benefit a significant number of patients. Tumours which are unresectable because of local advancement (involvement of major vessels or regional nodes) can be treated with RT alone or in combination with chemotherapy, but survival past 2 years is uncommon. Patients with liver metastases have a poor prognosis. As part of a programme of supportive care, some of these patients may receive cytotoxic therapy, the goal of which is to relieve cancer-related symptoms such as pain from the primary tumour or metastatic sites, or weakness, nausea and anorexia which may be associated with liver metastases. Although the objective response rate of chemotherapy agents is low, in an individual patient they may produce an adequate response and acceptable toxicity so that the patient experiences overall improvement in symptoms. The mainstay of chemotherapy for pancreatic cancer, as with other gastrointestinal cancers, has been fluorouracil. However, recent clinical data have shown that gemcitabine produces similar results in terms of response rate and survival, with more acceptable toxicity, so that the quality of life was judged to be better than with fluorouracil. Pancreatic cancer provides a fertile ground for testing new, biologically based approaches to cancer therapy because of the limited success of currently available treatments.
胰腺癌被医护人员和普通大众广泛视为最可怕的诊断之一。尽管在部分可手术患者系列中,长期生存几率可能达到20%,但大多数患者在诊断时病情不佳,对于所有新诊断患者群体而言,5年生存率很低。这种严峻的前景是多种因素共同作用的结果,包括解剖位置使筛查测试或症状难以早期发现、易扩散至区域淋巴结和肝脏、对化疗药物敏感性差以及许多患者在诊断时身体状况不佳。这些因素意味着在诊断时对这些患者进行仔细评估尤为重要,并且他们及其家人要充分了解可供选择的治疗方案以及相关的潜在风险和益处。对于局限性癌症,仅手术切除就有长期生存的可能。术后放疗(RT)的加入可预期地改善局部控制,但对生存影响极小,生存主要取决于肝转移的发生。随机试验数据支持在接受胰十二指肠切除术且切缘阴性的患者中使用氟尿嘧啶(5-FU)联合化疗和放疗,尽管益处不大且相关随机试验纳入的患者数量相对较少。对于肿瘤边缘可切除的患者,已证明在切除前使用化疗加放疗来缩小肿瘤大小是可行的,但尚不清楚这种方法是否会使大量患者受益。因局部进展(累及主要血管或区域淋巴结)而无法切除的肿瘤可单独用放疗或与化疗联合治疗,但生存超过2年并不常见。有肝转移的患者预后很差。作为支持性护理计划的一部分,其中一些患者可能会接受细胞毒性治疗,其目的是缓解与癌症相关的症状,如原发肿瘤或转移部位的疼痛,或可能与肝转移相关的虚弱、恶心和厌食。尽管化疗药物的客观缓解率较低,但对个体患者而言,它们可能产生足够的反应和可接受毒性,从而使患者症状总体改善。与其他胃肠道癌症一样,胰腺癌化疗的主要药物一直是氟尿嘧啶。然而,最近的临床数据表明,吉西他滨在缓解率和生存方面产生类似结果,毒性更易接受,因此生活质量被认为优于氟尿嘧啶。由于现有治疗方法取得的成功有限,胰腺癌为测试新的基于生物学的癌症治疗方法提供了肥沃土壤。