Lango Miriam N, Myers Jeffrey N, Garden Adam S
Department of Surgical Oncology, Head and Neck Section, Fox Chase Cancer Center, Philadelphia, PA, USA.
Semin Radiat Oncol. 2009 Jan;19(1):24-8. doi: 10.1016/j.semradonc.2008.09.005.
The addition of chemotherapy to radiation in the treatment of advanced-staged head and neck cancer has improved local-regional control and increased complete clinical and pathologic response rates in the neck. However, for those patients with residual neck disease on a posttreatment computed tomography (CT) scan, there remains significant controversy as to how to further assess the neck for the presence of a viable tumor and when to perform a neck dissection. Recently, investigators from Australia have assembled level I evidence to support the use of positron-emission tomography (PET) scanning to assess treatment response and have shown a very high negative predictive value for patients with a negative PET at 12 weeks after the completion of therapy. These data support the practice of observing PET-negative necks and intervening with neck dissection in PET-positive necks. However, not all investigators, practitioners, and patients are comfortable with delaying intervention for such a long time interval after treatment. The authors favor assessment of the neck with a CT scan at 6 weeks after the completion of chemoradiotherapy and recommend neck dissection for patients with radiographic residual disease at this time point. One rationale is that 6 weeks is an optimal window for operative intervention after acute treatment effects have subsided and before extensive fibrosis and scarring, which translates to less morbidity for the patient who is treated surgically. Another rationale is that those who develop regional recurrence can be hard to salvage surgically, and waiting an additional 6 weeks could allow for the expansion of resistant clones. The significance of this is unclear, however, because patients with residual disease are at a higher risk for local and distant as well as regional failure. Thus, further prospective studies of the role of postchemoradiotherapy PET scanning and neck dissection are needed.
在晚期头颈癌治疗中，放疗联合化疗可改善局部区域控制，并提高颈部的临床完全缓解率和病理完全缓解率。然而，对于治疗后计算机断层扫描（CT）显示颈部仍有残留病变的患者，如何进一步评估颈部是否存在存活肿瘤以及何时进行颈部清扫术仍存在重大争议。最近，澳大利亚的研究人员收集了一级证据支持使用正电子发射断层扫描（PET）来评估治疗反应，并显示在治疗完成12周后PET结果为阴性的患者具有非常高的阴性预测价值。这些数据支持对PET阴性的颈部进行观察，对PET阳性的颈部进行颈部清扫术的做法。然而，并非所有研究人员、从业者和患者都能接受在治疗后如此长的时间间隔内延迟干预。作者倾向于在放化疗完成6周后用CT扫描评估颈部，并建议在此时对影像学上有残留病变的患者进行颈部清扫术。一个理由是，6周是急性治疗效果消退后、广泛纤维化和瘢痕形成之前进行手术干预的最佳窗口，这对接受手术治疗的患者来说意味着更低的发病率。另一个理由是，那些发生区域复发的患者可能难以通过手术挽救，再等待6周可能会使耐药克隆扩增。然而，其意义尚不清楚，因为有残留病变的患者发生局部、远处以及区域复发的风险更高。因此，需要进一步对头颈部放化疗后PET扫描和颈部清扫术的作用进行前瞻性研究。
