Habermehl Daniel, Wagner Martin, Ellerbrock Malte, Büchler Markus W, Jäkel Oliver, Debus Jürgen, Combs Stephanie E
Department of Radiation Oncology, Klinikum Rechts der Isar, TU München, Munich, Germany,
Ann Surg Oncol. 2015;22(6):2068-74. doi: 10.1245/s10434-014-4219-z. Epub 2014 Nov 11.
Locally recurrent rectal cancer remains a dreaded event because curative resection is unlikely to be performed in a large number of cases. Carbon ion radiotherapy offers physical and biologic advantages. A high precise local dose deposition and sparing of normal tissue is possible. This work summarizes our experience on feasibility and early toxicity of carbon ion radiotherapy in previously irradiated and operated patients.
Between 2010 and 2013, a total of 19 patients with a median age of 62 years (range 14-76 years) received carbon ion irradiation to treat locally recurrent rectal cancer at the Heidelberg Ion Beam Therapy Center (HIT). All patients had a history of surgery and pelvic radiotherapy of at least 50.4 Gy. Median dose was 36 Gy [relative biologic efficacy (RBE)] [range 36-51 Gy(RBE)], and median planning target volume was 456 ml (range 75-1,597 ml). Some patients were treated in the recruiting phase I/II of the PANDORA study (NCT01528683).
Median follow-up was 7.8 months. Four patients were diagnosed with local relapse after carbon ion radiotherapy, and three patients developed distant metastases. Estimated mean local progression-free survival was 20.6 months by the Kaplan-Meier estimator. Two patients had preexisting rectovaginal fistula, and another patient had a preexisting presacral localized abscess formation in which the local relapse took place. No grade III or higher toxicities were observed.
Our first experiences in a pretreated patient group with a dismal prognosis are encouraging, and therapy-related side effects are mild. Longer follow-up is required to determine possible late effects and long-term disease control.
局部复发性直肠癌仍然是一个可怕的事件，因为在大量病例中不太可能进行根治性切除。碳离子放疗具有物理和生物学优势。可以实现高精确的局部剂量沉积并保护正常组织。这项工作总结了我们在先前接受过放疗和手术的患者中进行碳离子放疗的可行性和早期毒性方面的经验。
2010年至2013年期间，共有19例中位年龄为62岁（范围14 - 76岁）的患者在海德堡离子束治疗中心（HIT）接受碳离子照射以治疗局部复发性直肠癌。所有患者都有手术和盆腔放疗史，放疗剂量至少为50.4 Gy。中位剂量为36 Gy [相对生物效应（RBE）] [范围36 - 51 Gy（RBE）]，中位计划靶体积为456 ml（范围75 - 1597 ml）。一些患者在PANDORA研究（NCT01528683）的招募I/II期接受治疗。
中位随访时间为7.8个月。4例患者在碳离子放疗后被诊断为局部复发，3例患者发生远处转移。根据Kaplan-Meier估计器，估计的平均局部无进展生存期为20.6个月。2例患者先前存在直肠阴道瘘，另1例患者先前存在骶前局限性脓肿形成，局部复发发生在此处。未观察到III级或更高等级的毒性反应。
我们在预后不佳的预处理患者组中的初步经验令人鼓舞，且治疗相关的副作用较轻。需要更长时间的随访来确定可能的晚期效应和长期疾病控制情况。
