Garden A S, Weber R S, Morrison W H, Ang K K, Peters L J
Department of Radiotherapy, University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
Int J Radiat Oncol Biol Phys. 1995 Jun 15;32(3):619-26. doi: 10.1016/0360-3016(95)00122-F.
Surgery is the primary treatment for adenoid cystic carcinomas arising from major and minor salivary glands of the head and neck. However, local recurrence is frequent because of the infiltrative growth pattern and perineural spread associated with these tumors. At UTMDACC, we have had a longstanding policy of using postoperative radiotherapy to reduce the risk of local recurrence and to avoid the need for radical surgery; this 30-year retrospective study analyzes the results of this combined modality approach.
Between 1962 and 1991, 198 patients ages 13-82 years, with adenoid cystic carcinomas of the head and neck, received postoperative radiotherapy for known or suspected microscopic residual disease following surgery. Distribution of primary sites was: parotid: 30 patients; submandibular/sublingual: 41 patients; lacrimal: 5 patients; and minor salivary glands: 122 patients. Eighty-three patients (42%) had microscopic positive margins and an additional 55 (28%) had close (< or = 5 mm) or uncertain margins. One hundred thirty-six patients (69%) had perineural spread with invasion of a major (named) nerve in 55 patients (28%). Using radiation techniques appropriate to the primary site, a median dose of 60 Gy (range 50-69 Gy) was delivered to the tumor bed. Follow-up ranged from 5-341 months (median, 93 months). All surviving patients had a minimum of 2 years follow-up.
Twenty-three patients (12%) had local recurrences with 5-, 10-, and 15-year actuarial local control rates of 95%, 86%, and 79%, respectively. Fifteen of the 83 patients (18%) with positive margins developed local recurrences, compared to 5 of 55 patients (9%) with close or uncertain margins, and 3 of 60 patients (5%) with negative margins (p = 0.02). Patients with and without a major (named) nerve involved had crude failure rates of 18% (10 out of 55) and 9% (13 out of 143), respectively (p = 0.02). There was a trend toward better local control with increasing dose. This was significant in patients with positive margins, in whom crude control rates were 40 and 88% for doses of < 56 Gy and > or = 56 Gy, respectively (p = 0.006). Actuarial 5-, 10-, and 15-year freedom from relapse rates were 68%, 52%, and 45%, respectively. Base of skull and neck failures were uncommon with or without elective treatment, developing in 2 and 3% of patients, respectively. Distant metastases were the most common type of disease recurrence, developing in 74 patients (37%) of whom 62 (31%) were disease-free at the primary site.
Excellent local control rates were obtained in this population using surgery and postoperative radiotherapy and we recommend this combined approach for most patients with adenoid cystic carcinomas of the head and neck. Perineural invasion was an adverse prognostic factor only when a major (named) nerve was involved. Microscopic positive margins was also an adverse prognostic factor, but even when present, local control was achieved in over 80% of our patients. We recommend a dose of 60 Gy to the tumor bed, supplemented to 66 Gy for patients with positive margins. Despite effective local therapy, one-third of patients fail systemically, and good treatment to address this problem is lacking.
手术是头颈部大、小涎腺腺样囊性癌的主要治疗方法。然而，由于这些肿瘤的浸润性生长方式和神经周围扩散，局部复发很常见。在德克萨斯大学MD安德森癌症中心（UTMDACC），我们长期以来一直采用术后放疗来降低局部复发风险，并避免进行根治性手术；这项30年的回顾性研究分析了这种综合治疗方法的结果。
1962年至1991年间，198例年龄在13 - 82岁的头颈部腺样囊性癌患者在手术后因已知或怀疑有显微镜下残留病灶而接受了术后放疗。原发部位分布如下：腮腺：30例；颌下/舌下腺：41例；泪腺：5例；小涎腺：122例。83例（42%）患者显微镜下切缘阳性，另外55例（28%）切缘接近（≤5mm）或不确定。136例（69%）患者有神经周围扩散，其中55例（28%）侵犯主要（命名）神经。根据原发部位采用合适的放疗技术，肿瘤床的中位剂量为60Gy（范围50 - 69Gy）。随访时间为5 - 341个月（中位93个月）。所有存活患者至少随访2年。
23例（12%）患者出现局部复发，5年、10年和15年的精算局部控制率分别为95%、86%和79%。83例切缘阳性患者中有15例（18%）发生局部复发，而55例切缘接近或不确定的患者中有5例（9%），60例切缘阴性的患者中有3例（5%）（p = 0.02）。有和没有主要（命名）神经受累的患者粗失败率分别为18%（55例中的10例）和9%（143例中的13例）（p = 0.02）。随着剂量增加，局部控制有改善趋势。这在切缘阳性的患者中很显著，切缘阳性患者中，剂量<56Gy和≥56Gy时的粗控制率分别为40%和88%（p = 0.006）。5年、10年和15年的无复发生存率精算值分别为68%、52%和45%。无论是否进行选择性治疗，颅底和颈部失败都不常见，分别在2%和3%的患者中发生。远处转移是最常见的疾病复发类型，74例（37%）患者发生远处转移，其中62例（31%）原发部位无疾病。
采用手术和术后放疗在该人群中获得了良好的局部控制率，我们建议大多数头颈部腺样囊性癌患者采用这种联合治疗方法。仅当主要（命名）神经受累时，神经周围侵犯才是不良预后因素。显微镜下切缘阳性也是不良预后因素，但即使存在，我们超过80%的患者仍实现了局部控制。我们建议肿瘤床剂量为60Gy，切缘阳性患者补充至66Gy。尽管局部治疗有效，但三分之一的患者出现全身失败，且缺乏解决这一问题的良好治疗方法。
