Long Term Results of Radiation Therapy in Early Glottic Cancer

Purpose: This study was designed to evaluate long-term results in terms of failure, survival and voice preservation after radiation therapy for early glottic cancer. Materials and Methods: From February 1988 to December 2003, 70 patients with early glottic cancer were treated with radiation therapy at Keimyung University Dongsan Medical Center. Patient age distribution was from 39 to 79 years, with a median age of 62 years. All patients had squamous cell carcinoma. According to the TNM stage, 58 patients had stage I disease, 12 patients had stage II disease; 67 patients were male. The laryngeal area was irradiated with the use of bilateral opposing fields with/without a wedge filter with 6 MV photons at a total dose of $54{\sim}70.2$ Gy in $1.8{\sim}2.2$ Gy fractions over $6{\sim}8$ weeks. We delivered a median radiation dose of 60 Gy for stage I patients and a median radiation dose of 66 Gy for stage II patients. Salvage surgery was performed in patients with local recurrence. The voice preservation rate was analyzed after all treatments including salvage surgery. Follow-up periods were from 13 to 180 months, with a median follow-up period of 77.5 months. The survival rate was analyzed by the use of the Kaplan Meier method and log rank test. A comparison of two groups was performed with the use of the chi-squared test. Results: The local control rate was 98.5% (69/70). The five-year-overall survival rate was 93.9%. The five-year disease free survival rate (5YDFS) was 84.1% and the 5YDFS after radiation and salvage surgery was 92.8%. According to stage, the 5YDFS was 93.1% and 91.7% for stage I and stage II respectively. Thirteen patients (18.5%) had local failure with 24 months of median time to local failure and nine patients received salvage surgery; however, four patients were lost to follow-up after a diagnosis of recurrence. Only two patients died due to a distant metastasis at 33 months and 71 months after radiation therapy, respectively. Nine patients died due to other diseases with a median time of 73 months. There were no severe acute or chronic complications after radiation therapy. Voice preservation was ultimately achieved in 88.5% (62/70) of patients. Conclusion: We considered that radiation therapy was effective and we achieved excellent survival and voice preservation in early laryngeal cancer. The use of radiation therapy should be the first choice for the treatment of early glottic cancer.

초기 성문암의 방사선치료: 장기 추적결과

목적: 초기성문암에서 근치적 방사선치료는 성대를 보전하면서 완치할 수 있다. 저자들은 초기 성문암에서 방사선 치료 후 재발양상, 장기생존율 및 음성보존율을 알아보고자 하였다. 대상 및 방법: 1988년 2월부터 2003년 12월까지 계명대학교 방사선종양학과에서 초기(1, 2기) 성문부의 편평상피암으로 진단되어 방사선치료를 받은 환자 70명을 대상으로 하였다. 환자의 연령분포는 39세에서 79세로 중앙값 63세이며 병리학적으로 모두 편평상피암이었다. 병기로는 1기가 58명, 2기가 12명이었으며 남자가 67명으로 대부분을 차지하였다. 방사선치료선량은 하루 $1.8{\sim}2.2$ Gy 분할선량으로 총방사선량은 $54{\sim}70.2$ Gy로 병기 1기에는 중앙값 60 Gy, 2기에는 중앙값 66 Gy를 조사하였다. 추적관찰기간은 13개월에서 180개월로 중앙값이 77.5개월이었다. 생존율은 Kaplan Meier법을 사용하였으며 Log Rank법을 이용하여 분석하였다. 두 군 간의 비교는 Chi-square법을 이용하였다. 결과: 전체 환자에서 방사선치료 후 국소제어는 69명(98.5%)에서 되었으며 5년 생존율은 93.9%, 5년 무병생존율이 84.1%이었고 구제수술 후 5년 무병생존율은 92.8%로 1기는 93.1%, 2기는 91.7%이었다. 13명(18.5%)에서 국소재발을 하였으며 이 중 9명은 구제수술로 치료되었으며 4명은 재발을 진단받고 추적관찰이 되지 않았다. 방사선 치료 후 국소재발까지의 평균기간은 24개월($3{\sim}69$개월)이었다. 성문암으로 사망한 사람은 2명으로 폐, 뼈, 간의 전신전이로 각각 33, 71개월 후 사망하였고 9명은 성문암의 재발이나 전이 없이 다른 질환으로 평균 73개월 후 사망하였다. 방사선치료 후 심각한 만성 부작용은 없었다. 전체적으로 62명(88.5%)에서 음성을 보존할 수 있었다. 결론: 초기 성문암에서 방사선치료는 효과적인 치료법이며 우수한 장기생존율과 음성보존율을 얻을 수 있으므로 우선적으로 고려되어야 할 치료법이다.