Burkittリンパ腫の診断と治療

Burkitt's Lymphoma: Diagnosis and Therapy

Burkittリンパ腫は，進行が非常に速いが，治癒可能なB細胞リンパ腫で，腹部を中心とした節外病変を多く認め，腹痛や嘔吐，消化管出血，腸重積を主訴として発症することがある．骨髄や中枢神経系の浸潤もしばしば認める．診断は特徴的な組織所見を基本に，高度なKi-67陽性所見などの免疫形質の検討やMYC遺伝子などの遺伝子検索を含めて総合的に行う．進行が速いため，診断後直ちにCODOX-M/IVAC療法やhyper CVAD療法などの治療強度の高い化学療法を実施する．このような治療が実施できた場合，予後は良好である．リツキシマブ併用による上乗せ効果が認められ，特に強力な抗がん薬治療の施行が困難な患者の治療成績の改善が見込まれる．しかし，ランダム化試験は未実施で，今後の検討が必要である．

　BL（Burkitt's lymphoma）is an aggressive but curable B-cell lymphoma, and it usually Presents as an abdominal mass with a lesion（s）at an other extranodal site. The abdominal mass causes pain, vomiting, gastrointestinal bleeding, and intussusception. Some patients present with involvement of the bone marrow and the CNS（central nervous system）. The diagnosis of BL is based on histopathological features, including immunohistochemical staining for MKI67（old symbol : Ki-67）and detection of DNA rearrangements involving the MYC gene. BL is highly aggressive, and treatment should be immediately initiated after the diagnosis. The standard therapy for BL is intensive multi-agent chemotherapy, including CODOX-M/IVAC or hyper CVAD with CNS prophylaxis. The prognosis is favorable following intensive chemotherapy. Limited evidence suggests that a addition of rituximab improves the outcome of BL, and this regimen may be particularly valuable for weakened patients, who cannot tolerate intensive chemotherapy. However, no randomized controlled trials have been conducted to evaluate the addition of rituximab in BL and thus, further research is warranted.