Hughes E N, Shillito J, Sallan S E, Loeffler J S, Cassady J R, Tarbell N J
Joint Center for Radiation Therapy, Harvard Medical School, Boston, Massachusetts 02115.
Cancer. 1988 May 15;61(10):1992-8. doi: 10.1002/1097-0142(19880515)61:10<1992::aid-cncr2820611011>3.0.co;2-j.
In order to assess the efficacy of high-dose irradiation to the posterior fossa and low-dose irradiation to the spinal axis, we reviewed the results of 60 patients with biopsy-proven medulloblastoma treated at the Joint Center for Radiation Therapy (JCRT) between 1968 and 1984. The 5- and 10-year actuarial survival rates for all patients were 68% and 44%, respectively. The median time to recurrence was 19 months. Extent of surgery, age, and radiation dose to the posterior fossa all were of prognostic value. Complete or subtotal gross resection appeared to be a favorable prognostic indicator compared with biopsy only (P less than 0.05), with a 69% versus 40% actuarial survival rate at 5 years, respectively. Infants 2 years of age or less had a diminished 5-year actuarial survival rate of 48% (P less than 0.05) compared with older age groups. The posterior fossa was the predominant site of recurrence and accounted for 78% of all failures. Local control in the posterior fossa was dose dependent. Seventy-nine percent of the tumors that received 5000 cGy or greater were controlled versus only 33% of the tumors that received less than 5000 cGy (P less than 0.02). There were no supratentorial failures, and there was only one isolated spinal cord failure. There were no solitary spinal failures in 24 patients who received a median dose of only 2400 cGy to the spinal axis. We concluded that low-dose irradiation to the spine and whole brain may be indicated with maintenance of a posterior fossa dose of greater than 5000 cGy.
为了评估后颅窝高剂量照射和脊髓轴低剂量照射的疗效，我们回顾了1968年至1984年期间在联合放射治疗中心（JCRT）接受活检证实为髓母细胞瘤的60例患者的治疗结果。所有患者的5年和10年精算生存率分别为68%和44%。复发的中位时间为19个月。手术范围、年龄和后颅窝的放射剂量均具有预后价值。与仅行活检相比，完全或次全大体切除似乎是一个有利的预后指标（P小于0.05），5年精算生存率分别为69%和40%。2岁及以下的婴儿5年精算生存率为48%，低于年龄较大的组（P小于0.05）。后颅窝是复发的主要部位，占所有失败病例的78%。后颅窝的局部控制取决于剂量。接受5000 cGy或更高剂量的肿瘤中有79%得到控制，而接受低于5000 cGy的肿瘤中只有33%得到控制（P小于0.02）。幕上没有出现失败病例，仅有1例孤立性脊髓失败病例。24例接受脊髓轴中位剂量仅2400 cGy的患者中没有出现孤立性脊髓失败病例。我们得出结论，脊柱和全脑低剂量照射可能适用于后颅窝剂量维持在5000 cGy以上的情况。
