Pollack A, Zagars G K, Goswitz M S, Pollock R A, Feig B W, Pisters P W
Department of Radiation Oncology, The University of Texas, M. D. Anderson Cancer Center, Houston, USA.
Int J Radiat Oncol Biol Phys. 1998 Oct 1;42(3):563-72. doi: 10.1016/s0360-3016(98)00277-6.
Radiotherapy for soft tissue sarcoma is typically preoperative or postoperative, with advocates of each. In this study, the relationship of the sequencing of radiotherapy and surgery to local control was examined.
The cohort consisted of 453 patients with Grade 2-3 malignant fibrous histiocytoma, synovial sarcoma, or liposarcoma treated from 1965-1992. Retroperitoneal sarcomas were excluded. Median follow-up was 97 months. There were 3 groups of patients that were classified by the treatment administered at our institution: preoperative radiotherapy to a median dose of 50 Gy given before excision at MDACC (Preop; n = 128); postoperative radiotherapy to a median dose of 64 Gy given after excision at MDACC (Postop; n = 165); and radiotherapy to a median dose of 65 Gy without excision at MDACC (RT Alone; n = 160). Those in the RT Alone Group had gross total excision at an outside center prior to referral.
Histological classification, whether locally recurrent at referral, and final MDACC margins were independent determinants of local control in Cox proportional hazards multivariate analysis using the entire cohort. The type of treatment was not significant; however, tumor status at presentation (gross disease vs. excised) affected these findings greatly. Gross disease treated with Preop was controlled locally in 88% at 10 years, as compared to 67% with Postop (p = 0.01). This association was independently significant for patients treated primarily (not for recurrence). In contrast, for those presenting after excision elsewhere, 10-year local control was better with Postop (88% vs. 73%,p = 0.07), particularly for patients treated primarily (91% vs. 72%, p = 0.02 in univariate analysis; p = 0.06 in multivariate analysis). Re-excision at MDACC (Postop) resulted in enhanced 10-year local control over that with RT Alone (88% vs. 75%, p = 0.06), and was confirmed to be an independent predictor in multivariate analysis (p = 0.02).
Local control was highest with Preop in patients presenting primarily with gross disease, and with Postop in patients presenting primarily following gross total excision. The data suggest that 50 Gy is inadequate after gross total excision, possibly due to hypoxia in the surgical bed.
软组织肉瘤的放疗通常在术前或术后进行，两种方式都有其支持者。在本研究中，探讨了放疗与手术顺序对局部控制的关系。
该队列由1965年至1992年期间治疗的453例2-3级恶性纤维组织细胞瘤、滑膜肉瘤或脂肪肉瘤患者组成。排除腹膜后肉瘤。中位随访时间为97个月。根据我们机构给予的治疗方法将患者分为3组：在MD安德森癌症中心（MDACC）切除术前给予中位剂量50 Gy的术前放疗（术前组；n = 128）；在MDACC切除术后给予中位剂量64 Gy的术后放疗（术后组；n = 165）；以及在MDACC未进行切除给予中位剂量65 Gy的单纯放疗（单纯放疗组；n = 160）。单纯放疗组的患者在转诊前在外部中心进行了根治性切除。
在使用整个队列的Cox比例风险多变量分析中，组织学分类、转诊时是否局部复发以及MDACC最终切缘是局部控制的独立决定因素。治疗类型无显著意义；然而，就诊时的肿瘤状态（大体疾病与已切除）对这些结果有很大影响。术前放疗治疗的大体疾病在10年时局部控制率为88%，而术后放疗为67%（p = 0.01）。这种关联对主要接受治疗的患者（而非复发患者）具有独立显著性。相比之下，对于在其他地方切除术后就诊的患者，术后放疗的10年局部控制更好（88%对73%，p = 0.07），特别是对于主要接受治疗的患者（单变量分析中91%对72%，p = 0.02；多变量分析中p = 0.06）。在MDACC进行再次切除（术后组）导致10年局部控制率高于单纯放疗组（88%对75%，p = 0.06），并且在多变量分析中被确认为独立预测因素（p = 0.02）。
对于主要表现为大体疾病的患者，术前放疗的局部控制率最高；对于主要在根治性切除术后就诊的患者，术后放疗的局部控制率最高。数据表明，根治性切除术后50 Gy剂量不足，可能是由于手术床缺氧。
