Wei-wei Liu, Qiu-liang Wu, Guo-hao Wu, Zhi-hua Chen, Zong-yuan Zeng
Department of Combined Therapy No. 3, Cancer Center of Sun Yat-sen University, Guang zhou 510-060, P.R. China.
Laryngoscope. 2005 Sep;115(9):1574-9. doi: 10.1097/01.mlg.0000173166.48440.e4.
Postirradiation osteosarcoma (PIOS) arising after radiation of nasopharyngeal cancer (NPC) is rare and seldom reported. In this article, we report its clinicopathologic features, outcome, and prognostic factors.
Retrospective cohort study.
Fifteen patients with NPC were determined to have PIOS after reviewing 426 patients with osteogenic sarcomas. Their clinical records, image and pathologic slides, and follow-up data after treatment were collected to perform analysis.
The incidence rate of PIOS in NPC was approximately 0.037% (15/40,719), which occupied approximately 3.5% (15/426) among all kinds of osteogenic sarcomas. The latent time of PIOS after irradiation for NPC ranged from 4 to 27 years, with a mean of 13.3 years. The location where PIOS arose included 33.3% (5/15) from maxilla, 46.7% (7/15) from mandible, and 20% (3/15) from a mixture of nasal cavity and paranasal sinuses. Radiologically, soft tissue mass, bone destruction, and tumor new bone formation were the main characteristics. Pathologic subtypes included 53.3% (8/15) of fibroblastic osteosarcoma, 33.3% (5/15) of chondroblastic osteosarcoma, and 13.3% (2/15) of mixed type osteosarcoma. Of 15 patients with PIOS, 12 patients were treated with curative intent, and the remaining 3 patients with palliative intent. For 12 patients who had undertaken ablative surgery, 1 patient had residual tumor, and 6 patients had tumor recurrence. The survival time after treatment for all patients ranged from 7 to 41 months, with a mean of 18 months. Kaplan-Meier estimates of 1 year and 2 year survival rates were 60% and 24%, respectively. Statistical analysis showed that sex and tumor bone formation are significant prognostic factors.
PIOS in NPC is a highly malignant disease with poorer prognosis than in other sites. Surgery combined with pre- and postoperative chemotherapy might be an effective way to improve survival.
鼻咽癌（NPC）放疗后发生的放射后骨肉瘤（PIOS）罕见，鲜有报道。在本文中，我们报告其临床病理特征、转归及预后因素。
回顾性队列研究。
在对426例骨肉瘤患者进行回顾性分析时，确定有15例NPC患者发生了PIOS。收集他们的临床记录、影像及病理切片，以及治疗后的随访数据进行分析。
NPC中PIOS的发生率约为0.037%（15/40719），在所有类型的骨肉瘤中约占3.5%（15/426）。NPC放疗后PIOS的潜伏期为4至27年，平均为13.3年。PIOS发生的部位包括上颌骨33.3%（5/15）、下颌骨46.7%（7/15）、鼻腔和鼻窦混合部位20%（3/15）。影像学上，软组织肿块、骨质破坏和肿瘤新生骨形成为主要特征。病理亚型包括纤维母细胞性骨肉瘤53.3%（8/15）、软骨母细胞性骨肉瘤33.3%（5/15）、混合型骨肉瘤13.3%（2/15）。15例PIOS患者中，12例接受了根治性治疗，其余3例接受了姑息性治疗。12例接受了根治性手术的患者中，1例有肿瘤残留，6例有肿瘤复发。所有患者治疗后的生存时间为7至41个月，平均为18个月。Kaplan-Meier法估计的1年和2年生存率分别为60%和24%。统计分析表明，性别和肿瘤骨形成是显著的预后因素。
NPC中的PIOS是一种高度恶性疾病，预后比其他部位的骨肉瘤更差。手术联合术前和术后化疗可能是提高生存率的有效方法。
