대한내과학회지 : 제 76 권제 1 호 9 미만성거대 B세포림프종환자치료후절대림프구수감소율의예후적가치 1 경북대학교의과대학내과학교실, 경북대학교병원조혈모세포이식센터 김시내 1 채의수 1, 김종광 1, 문준호 1, 이수정 1 김윤정 1 이유진 1 손상균 1, Prognostic value of the absolute lymphocyte count reduction in patients with diffuse large B cell lymphoma treated with R-CHOP Shi Nae Kim, M.D. 1, Yee Soo Chae, M.D. 1,, Jong Gwang Kim, M.D. 1,, Joon Ho Moon, M.D. 1,, Soo Jung Lee, M.D. 1, Yun Jeong Kim, M.D. 1, Yoo Jin Lee, M.D. 1 and Sang Kyun Sohn, M.D. 1, 1 Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea; Stem Cell Transplantation Unit, Kyungpook National University Hospital, Daegu, Korea Background/Aims: The International Prognostic Index (IPI) and absolute lymphocyte count (ALC) are prognostic factors in diffuse large B cell lymphoma (DLBCL). Nevertheless, in the Rituximab era, a new predictive marker related to Rituximab might be needed. We evaluated prognostic factors for survival in patients with early stage DLBCL after R-CHOP (Rituximab, cyclophosphamide, adriamycin, vincristine, prednisolone) treatment. Methods: From Aug 3 to Nov 7, 78 patients with early stage DLBCL, who finished R-CHOP as scheduled, were reviewed retrospectively. Survival analyses were performed according to clinical parameters (age, performance status, lactate dehydrogenase (LDH), extra-nodal involvement, stage, ALC, and the rates of reduction of the white blood count (WBC) and ALC). Results: Of the 78 patients with early stage DLBCL, 6 (33.3%) were classified as stage I. Seventy-three patients (93.6%) presented with a good performance status, while LDH was elevated in patients (5.6%). According to the IPI, 67 (85.9%), 8 (1.3%), and 3 (3.8%) patients were classified in the low, low-intermediate, and high-intermediate risk groups, respectively. The overall response rate was 1%, including a 94.8% complete response. Survival analysis demonstrated that the rate of reduction of ALC following the first cycle of the R-CHOP regimen was the only factor associated with time-to-progression (p=.37), whereas age was the single most important prognostic factor for overall survival (p=.6). Conclusions: In our study, the rate of reduction of ALC in addition to age and IPI was found to be a significant prognostic factor in patients with early stage DLBCL treated with the R-CHOP regimen. (Korean J Med 76:5-59, 9) Key Words: Absolute lymphocyte count; Rituximab; DLBCL Received: 8. 5. 17 Accepted: 8. 8. 1 Correspondence to: Sang Kyun Sohn, M.D., Ph.D., Department of Hematology/Oncology, Kyungpook National University Hospital, Kyungpook National University School of Medicine 5 Samduck -ga, Jung-gu, Daegu 7-71, Korea Email: sksohn@knu.ac.kr - 5 -
- Shi Nae Kim, et al. Absolute lymphocyte count reduction in patients with early-staged DLBL receiving R-CHOP - 서 론 대상및방법 리툭시맙 (Rituximab) 을 cyclophosphamide, adriamycin, vincristin and prednisone (CHOP) 병합요법에추가함으로서미만성거대 B세포림프종의치료효과가크게향상되어, 일차표준치료제로널리사용되고있다 1-3). 리툭시맙 (Mabthera, Roche, Swiss) 은종양치료목적으로상용화되어미국 FDA 로부터최초로승인된 chimeric 단클론성항체치료제이다. 리툭시맙의생체내기전은충분히알려져있지않지만, 주로보체매개성세포독성 (complement-mediated cytotoxicity), 항체매개성세포독성 (antibody-dependent cell-mediated cytotoxicity) 및세포자연사멸 (apoptosis) 에관여하는것으로추정된다 4-6). 1993년 International Non-Hodgkin s Lymphoma Prognosis Factor Project에서는비호지킨림프종환자의예후에관련되는여러인자들을분석하여국제예후지표 (Internatinal prognostic index, IPI) 로서발표하였다. 그후 IPI는미만성거대 B세포림프종의예후평가에널리사용되고있으나미만성거대 B 세포림프종의표준치료인 Rituximab-CHOP (R-CHOP) 하에서 IPI의임상적가치에대한재평가와다른예후인자들에대한분석이필요하다. 이전연구에서미만성거대 B세포림프종및여포성림프종환자의치료전말초혈액내림프구수가치료반응및예후와관련이있음을보고한바있다 7-9). 또한, 항체매개성세포면역에관여하는세포 ( 대식세포, NK 세포, 수지상세포 ) 의 Fc 수용체발현에관계하는 FcR IIIa 유전자의이형성에따라 R-CHOP에대한미만성거대 B세포림프종의다양한치료반응이보고된바있어리툭시맙에대한생체내반응과림프구가치료에중요한역할을할것으로추정된다 1). 리툭시맙의치료표적인 CD은림프종세포뿐만아니라정상 B 림프구에도발현되어있으므로, 리툭시맙의정맥투여는말초혈액에서 B 세포의감소를일으킬것으로예상되며, 이러한 B 세포의감소는절대림프구수의감소와상관관계가있으며, 리툭시맙치료전후의말초혈액내림프구수를측정함으로서리툭시맙의림프종에대한효과를예측할수있을것으로추정된다. 이에본연구에서는임상병기 1, 기의미만성거대 B 세포림프종환자를대상으로 R-CHOP치료시말초혈액절대림프구수및감소정도와치료반응및생존율과의상관관계를조사하고자하였다. 1. 대상환자및치료 3년 8월부터 7년 8월까지경북대학교병원에서미만성거대 B 세포림프종으로진단받고 R-CHOP요법으로치료받은환자중, Ann Arbor stage가 I 또는 II인 78명환자를대상으로후향적으로조사하였으며, 대용적림프종 (bulky lymphoma) 인경우는제외하였다. 환자는나이, 임상수행능력 (performance status), lactate dehydrogenase (LDH), 림프절외침범부위및 IPI 등급에따라분류하였다. 치료는제 1병일에리툭시맙 375 mg/m 을 5% dextrose 5 ml에혼합하여첫 1시간동안은 5/ ml/hr로정주후 1 ml/hr 속도로주입하였다. 리툭시맙투여후 cyclophosphamide 75 mg/m, adriamycin 5 mg/m, vincristin mg 을순차적으로주사하였고, 1 mg의 prednisolone을 5일간경구복용하였다. R-CHOP은 4~6 주기를원칙으로하였으나, 병소부위국소적방사선치료 (involved field Radiotherapy) 를계획한환자의경우 R-CHOP요법을 3주기시행받은환자도포함하였다.. 말초혈액림프구수측정절대림프구수는첫리툭시맙포함한병합화학요법치료첫째날 (Day 1) 과 3주째 (Day 1) 말초혈액검사를통해측정하였다. 절대림프구수의 Day 1과 Day 1의차이를 Day 1의절대림프구수로나눈값의백분율이절대림프구수감소율로정의하였으며, 중앙값을기준으로두군으로나누어임상적특징과치료반응및생존율을비교하였다. 3. 치료반응과생존율의평가치료반응의평가는이학적검사와전산화단층촬영술 (computed tomography, CT) 을기본으로하여 ~3 주기마다평가하였으며, 반응정도는 International Working Group의기준으로하였다 11). 전체생존율 (Overall survival, ) 은치료시작일부터사망일또는마지막관찰시점까지로정의하였고, 질병진행기간 (Time to progression, ) 은치료시작일부터병의진행또는재발된시점이나마지막관찰시점으로정의하였다. 4. 통계적분석절대림프구수감소율의중앙값을기준으로두군으로나 - 53 -
- 대한내과학회지 : 제 76 권제 1 호통권제 581 호 9 - 누어, Chi-square test와 Student t-test를이용하여각각의지표를비교하였다. 누적생존율은 Kaplan-Meiyer 방법을이용하여분석하였으며, log-rank 분석으로두군간의차이를비교하였다. 통계처리는 SPSS version 13 (Chicago, IL, US) 을이용하여분석하였다. 결과 1. 환자의특성및치료경과전체 78명의환자의중앙추적기간은 53.5일 ( 범위 : 11~ 1319일 ) 이었다. 연령의중앙값은 56세 ( 범위, 4~81세 ) 였으며남자가 49명 (6.8%) 이었다. 활동수행능력은 ECOG or 1 경우가 73명 (93.6%) 으로대부분을차지하였으며, stage I 및 II는각각 6명 (33.3%), 5명 (66.7%) 이었다. LDH 가증가한경우 (LDH >48IU/L) 는 명 (5.6%) 이고, 림프절외침범이있는환자가 6명 (33.3%) 이었으나 곳이상인환자는없었다. International prognostic index (IPI) 기준으로저위험군, 저중등위험군, 고중등위험군은각각 67명 (85.9%), 8명 (1.3%), 3 명 (3.8%) 이었다. R-CHOP요법평균치료횟수는 6주기 ( 범위, 3~8 주기 ) 였으며, 완전관해를보인경우가 74명 (94.9%) 이고부분반응이 4 명 (5.%) 으로전체가부분관해이상의반응을보였다. 39명 (5.%) 의환자에서병소부위국소적방사선치료 (involved field Radiotherapy) 를받았다. 치료후재발또는진행은 5명 (6.4%) 에서있었으며그중 3명이구제항암화학요법을실시하였고, 1예에서자가조혈모세포이식치료를받았다. 사망은 5명으로원인은질병의진행이 예였으며, 패혈증쇽, 간질성폐렴그리고, 불명이각각 1예씩있었다 ( 표 1).. 절대림프구수감소율과그에따른두군의비교첫째주기의치료직전 (Day 1) 과두번째주기의치료직전 (Day 1) 말초혈액절대림프구수는중앙값이 175 1 6 /L ( 범위 : 398~3531 1 6 /L) 와 1794 1 6 /L( 범위 : 537~368 1 6 /L) 였으며, 절대림프구수감소율의평균값은 8.59% ( 범위 : -31~6%) 였다. 이를중심으로절대림프구수감소율이평균값보다낮은군을 A군, 나머지를 B군으로정의하였다. A군의경우 Day 1 절대림프구수평균 146 1 6 /L에서 Day 1 절대림프구수평균이 194 1 6 /L로증가하여절대림프구수감소율평균이 -1.1% ( 범위 : -31~8%) 이었다. B군의경우는 Day 1 절대림프구수평균 179 1 6 /L에서 Day 1 절대 림프구수평균이 15 1 6 /L로감소되어절대림프구수감소율평균이.4% ( 범위 : 9~6%) 이었다. 두군간의환자특성및병기에있어서의미있는차이는보이지않았으나, 림프구감소율이낮은군 (A군) 에서 5명이재발또는진행하였으나, 감소율이높은군 (B군) 에서는재발이없었다 ( 표 1). 3. 생존분석 Log-rank 분석에의한생존율을절대림프구수및백혈구감소율과절대림프구수감소율에대해분석한결과절대림프구수및백혈구감소율과생존율은유의한상관관계를보이지않은것에비해절대림프구수감소율이높은경우통계적으로유의하게무병진행기간이길었다 (p=.37, 그림 1). 생존율에영향을미칠수있는인자인나이, 임상적병기, 행동수행능력, LDH 와 IPI 등에대해각각분석을실시하였다. 그결과나이가 6세보다많은환자에서전체생존율이의미있게낮았고 (p=.6, 그림 A) IPI 위험도에따른무진행기간이차이가있었다 (p=.5, 그림 C). 그러나임상적병기 (I vs. II기 ), LDH ( 정상 vs. 증가 ), 행동수행능력 (,1 vs. 이상 ), IPI 위험군에따른생존율은통계적으로의미있는차이를보이지않았다 ( 그림 ). 고찰 CHOP 병합요법을이용한림프종의치료에서 IPI 및치료전림프구수가예후에관계가있다고알려져있으나 7), 리툭시맙을포함한치료에서는예후인자에대한재평가가필요하여본연구에서는 R-CHOP요법으로치료한국소미만성거대 B세포림프종환자를대상으로예후와관계된인자를분석하고자하였다. 그결과 R-CHOP요법전후의림프구수감소가큰경우무진행기간 () 이의미있게높음을알수있었다. 자가조혈모세포이식치료이후절대림프구수의역할에대한연구에서절대림프구수의회복이자가조혈모세포이식후면역상태의표지자이며생존율에대한의미있는예측인자임을보고한바있다 1, 13). 또한미만성거대 B 세포림프종에서 CHOP 또는 R-CHOP 요법이후절대림프구수의회복이더높은생존율을예측해주고이는 IPI와독립적인자로작용한다고한다 14, 15). 리툭시맙의표적인 CD은 B 림프종세포뿐아니라, pre-b세포및성숙 B 세포 (mature B cell) 에발현되어있어 16), 리툭시맙치료후에는림프종세포뿐만아니라말초혈액내 B 세포도감소하게된다. 이와같은 B 세포감소와관련 - 54 -
- 김시내외 7 인. 미만성거대 B 세포림프종환자치료후절대림프구수감소율의예후적가치 - Table 1. Patient characteristics and treatment outcomes according to the rate of reduction of the absolute lymphocyte count after R-CHOP Median age (yrs) (range) Sex (F/M) (%) Stage 1 PS, ECOG,1 All patients n=78 56 (4-81) 9/49 (37./6.8) 6 (33.3) 5 (66.7) 73 (93.6) Group A * n=39 59.5 (4-81) 15/4 (38.5/61.5) 1 (3.8) 7 (69.) 36 (9.3) Group B * n=39 54. (9-75) 14/5 (35.9/64.1) 14 (35.9) 5 (64.1) 37 (94.9) p-value Extranodal 1 Elevated LDH IPI Low Low-intermediate High-intermediate Radiotherapy Response CR PR ALC, range Day 1 Day 1 Reduction rate (%)(range) Recurrence Death Causes of death Progression Infection Others 5 (6.4) 5 (66.7) 6 (33.3) (5.6) 67 (85.9) 8 (1.3) 3 (3.8) 39(5) 74 (94.9) 4 (5.1) 175 (398-3531) 1794 (537-368) 8.59 (-31-6) 5 (6.4) 5 (6.7) 1 3 (7.7) 3 (76.9) 9 (3.1) 11 (8.) 3 (84.) 5 (13.) 1 (.6) 17 (43.6) 37 (94.9) (5.1) 146 (398-79) 194 (635-368) -1.1 (-31-8) 5 (1.5) 3 (8.3) 1 (5.1) (56.4) 17 (43.6) 9 (3.1) 35 (87.5) 3 (7.5) (5.1) (56.4) 37 (94.9) (5.1) 179 (778-3531) 15 (537-37).4 (9-6) (5.1).55.64.63.58 1. 1...1.578 * The two groups were separated using the median rate of reduction of ALC. Group A had the lower rate of reduction of ALC and Group B had the higher rate. elevated LDH: >48 IU/L other: interstitial pneumonitis, not evaluated LDH, lactate dehydrogenase; ECOG, Eastern Cooperative Oncology Group; IPI, International Prognostic Index; CR, complete response; PR, partial response; ALC, absolute lymphocyte counts.488.815.631.644 하여류마티스환자에서리툭시맙치료시말초혈액내 B 세포감소가 1개월에 97% 에서보이며 T 세포와 NK 세포에는영향이없었다 17). 그리고미만성거대 B 세포림프종환자를대상으로한이전의연구에서리툭시맙에대한면역세포의 Fc 수용체의유전자다형성에따른치료반응율이다름을 보인바있어리툭시맙에대한 CD의반응도및면역세포의활성도는개인마다차이를보일것으로추정되며, 말초혈액내의림프구수감소정도도개인차이가있으며, 치료전후의림프구수감소율을측정하여리툭시맙에대한반응도를예측할수있을것으로생각된다 1). 실제로, 류마티스 - 55 -
- The Korean Journal of Medicine: Vol. 76, No. 1, 9 - A) Absolute lymphocyte count (ALC) p=.83 p=.49 B) Reduction rate of WBC p=.97 p=.79 C) Reduction rate of ALC p=.37 p=.844, Time to progression;, overall survival Figure 1. Survival according to the absolute lymphocyte count (ALC)(A) and the rates of reduction of WBC (B) and ALC (C) - 56 -
- Shi Nae Kim, et al. Absolute lymphocyte count reduction in patients with early-staged DLBL receiving R-CHOP - A) Age 6 6 >6 >6 p=.398 p=.6 B) Stage p=.131 p=.687 C) IPI p=.5 p=.16, Time to progression;, overall survival Figure. Survival according to age (A), stage (B), and the International Prognostic Index (IPI)(C) - 57 -
- 대한내과학회지 : 제 76 권제 1 호통권제 581 호 9 - 관절염환자에서리툭시맙치료시림프구수감소정도가증상완화및임상증상의호전과관계가있음을보고하였으며 18), 류마티스환자에서리툭시맙치료후 B 세포의감소하였다가다시회복하는과정과재발에대한관찰에서 B 세포의회복전에는재발이없음을확인하였다 19). 또한재발성진행이느린림프종 (indolent lymphoma) 환자를리툭시맙단독으로치료한연구에서 B 세포감소가없었던환자에서반응율이낮음을보고한바있다 ). 그러므로말초혈액내절대림프구수감소정도로 R-CHOP 요법시반응율을예측할수있고이는생존율의예측인자로역할을할수있을것으로생각된다. 하지만이번연구에서정확한결론을유추하기에몇가지제한점이있다. 초기병기환자를대상으로하였기때문에전체재발율이낮았고절대림프구수감소율이작은군에서재발한환자가없었다. 그래서통계적으로의미있는결과를이끌어내기위한사건 (event) 과대상환자수가적어 Cox 회귀분석을이용하여림프구수감소율의위험비 (Hazard ratio) 를구하지못하였다. 또한리툭시맙의직접적인작용대상인 B 림프구의수를확인한것이아니라전체림프구수를측정하였고, 이중 3~4% 만이 B 세포임을고려한다면 B-세포에대한작용을직접적으로볼수없다는단점이있다. 그러나이전연구에서리툭시맙을사용한경우말초혈액내 T 림프구와 NK 세포수는감소를보이지않았음을보고한바있어치료전후의 B세포를포함한림프구세포분석에대한추가적인연구가필요하다 17, ). 그리고림프구수측정을위한적절한시점과항암제요법의영향에대한고려가필요하다. 류마티스관절염환자를대상으로한리툭시맙단독또는항암제병합요법의연구에서리툭시맙의평균반감기는 19~일이며, 항암요법유무에따른변화가크지않았다 19). 또한, 악성림프종을대상으로한연구에서리툭시맙치료후 CD 양성 B 세포가 6개월까지감소되어있음을보고한바가있다 ). 본연구에서도전체백혈구수변화율과무진행기간은통계적으로의미가없었고, 주기 R-CHOP 요법전림프구수검사는항암요법의영향에서회복되어큰문제가되지않을것으로사료된다. 결론적으로본연구에서절대림프구수의감소율이미만성거대 B 세포림프종환자의 R-CHOP 요법시무진행기간과관계가있음을확인하였고, 간단한혈액학적검사로환자의예후를예측하는데도움이될수있을것으로사료된다. 그러나추후연구에서대규모의환자들을대상으로 B 림프구의수를측정하여 B 림프구수의감소율에대한예후인자로서의분석이추가로필요하다. 요 목적 : 미만성거대 B 세포림프종에서 IPI와절대림프구수는예후인자로알려져있다. 그러나리툭시맙을이용한치료에있어리툭시맙과관련하여새로운예후인자가필요할것으로생각된다. 이에저자는초기병기의미만성거대 B 세포림프종환자에서 R-CHOP 요법의생존율관련예후인자를평가하였다. 방법 : 3년 8월부터 7년 11월까지내원한초기병기의미만성거대 B 세포림프종환자로계획된 R-CHOP 요법을시행받은마친 78명을후향적으로조사하였다. 생존율분석을위해연령, 임상수행능력, LDH, 림프절외침범, 병기, 절대림프구수, 백혈구감소율및절대림프구수감소율에대해평가하였다. 결과 : 초기병기의미만성거대 B 세포림프종환자 78명중 6명 (33.3%) 은병기 1기였고, 73명의환자들은좋은임상수행능력을보였으며 명의환자에서 LDH 증가를보였다. IPI 분류시저위험군은 67명 (85.9%) 이고, 저중등군은 8명 (1.3%), 고중등군은 3명 (3.8%) 이었다. 전체반응율은 1% 로서완전관해율이 94.8% 였다. 생존율분석시전체생존율에서는연령이가장중요한예후인자였고 (p=.6), 무진행 생존율에있어서는첫 R-CHOP 요법후절대림프구수감소율이유일한예후인자였다 (p=.37). 결론 : 본연구에서초기병기의미만성거대 B 세포림프종환자에서 R-CHOP 요법시나이, IPI와함께절대림프구수감소율이의미있는예후인자임을알수있었다. 중심단어 : 절대림프구수 ; 리툭시맙 ; 미만성거대 B세포림프종 약 REFERENCES 1) Coiffier B, Lepage E, Briere J, Herbrecht R, Tilly H, Bouabdallah R, Morel P, van den Neste E, Salles G, Gaulard P, Reyes F, Lederlin P, Gisselbrech C. CHOP chemotherapy plus rituximab compared with CHOP alone in elderly patients with diffuse large-b-cell lymphoma. N Engl J Med 346:35-4, ) Feugier P, van Hoof A, Sebban C, Solal-Celigny P, Bouabdallah R, Fermé C, Christian B, Lepage E, Tilly H, Morschhauser F, Gaulard P, Salles G, Bosly A, Gisselbrecht - 58 -
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