18F-FDG PET/CT显像在淋巴瘤肌肉侵犯评价中的价值

The value of 18F-FDG PET/CT imaging in the evaluation of muscle invasion in lymphoma

目的探讨淋巴瘤肌肉侵犯病灶18氟-脱氧葡萄糖(18F-FDG)正电子发射断位显像/计算机断层显像(PET/CT)的特点,并比较PET和CT对淋巴瘤肌肉侵犯病灶的检测效能。方法回顾性分析34例淋巴瘤肌肉侵犯患者的PET/CT图像特征,并与34例非淋巴瘤患者的18F-FDG PET/CT肌肉生理性浓聚进行比较。通过分析淋巴瘤肌肉侵犯病灶的PET代谢肿瘤/非肿瘤比值(T/NT ratio)及同病灶CT密度T/NT比值,探讨PET和CT对病灶的探测能力。同时研究淋巴瘤肌肉侵犯与血清乳酸脱氢酶(LDH)及肌酸激酶(CK)水平的关系。结果34例肌肉淋巴瘤患者中,88.2%为非霍奇金淋巴瘤(NHL),11.8%为霍奇金淋巴瘤。其中老年患者的国际预后指数(IPI)及分期更高。70.5%表现为局限性肌肉侵犯,29.5%表现为全身肌肉广泛侵犯。最常累及的肌肉为髂腰肌、腰大肌和臀部肌肉。淋巴瘤肌肉侵犯病灶18F-FDG摄取明显高于肌肉生理性浓聚(t=4.838,P<0.0001)。淋巴瘤肌肉侵犯均未累及头颈部肌肉且79.4%病灶呈现为结节状和块状,而肌肉生理性浓聚52.9%位于头颈部且均表现为沿肌肉走行的条状或片状浓聚。淋巴瘤肌肉侵犯病灶18F-FDG明显高摄取,显示清楚,而在CT上病灶密度改变不明显,难以确认。病灶处PET代谢T/NT比值明显高于CT密度T/NT比值(t=7.515,P<0.0001)。患者的肿瘤侵犯范围及病灶代谢增高程度均与血清LDH和CK水平无相关性(P>0.05)。结论18F-FDG PET/CT能灵敏地、全面地检出淋巴瘤肌肉侵犯病灶,并能很好地与肌肉生理性浓聚相鉴别。淋巴瘤肌肉侵犯的18F-FDG代谢与血浆LDH和CK水平无关。

Objective To analyze the value of 18 F-FDG PET/CT imaging in the evaluation of muscle invasion in lymphoma. Methods 18 F-FDG PET/CT imaging of 34 patients with muscle invasion in lymphoma were retrospective analyzed.Imaging characteristics of PET/CT were recorded and compared with those of the muscle physiological uptake in 34 patients with non-lymphoma disease.Metabolic T/NT ratio on PET and density T/NT ratio on CT were measured to evaluate the detectability of PET and CT for muscle lymphoma.Meanwhile the relationship of muscle lymphoma involvement and serum lactate dehydrogenase(LDH) and creatine kinase(CK) were investigated. Results Of 34 patients with muscle lymphoma,88.2% were non-hodgkin lymphoma (NHL),including 44.1% diffuse large B cell lymphoma,and 11.8% were Hodgkin lymphoma (HD).The international prognostic index (IPI) and staging of lymphoma were higher in elderly patients.Localized muscle involvement was found in 70.5% of the patients,while 29.5% presented with systemic involvements.The most commonly involved muscles were the iliac muscles,the psoas major muscles and the gluteal muscles.18F-FDG uptake in muscle lymphoma was significantly higher than that of muscle physiological uptake( t =4.838,P < 0.000 1 ).79.4% of the lesions were nodular or massive,while the physiological uptake presented as strip or sheet radioactivity accumulation,which distributed along the muscle.52.9% of muscle physiological uptake was located in the muscles of head and neck,however,none muscle lymphoma was found in the muscle in this region.Intense uptake of 18F-FDG was observed in all of the muscle lymphoma with a clear margin,however,the density change on CT was obscured with normal density in 5 cases,slightly decreased density in 28 cases and slightly increased density in one case.Metabolic T/NT ratio of the lesions on PET was significantly higher than that of density T/NT ratio on CT( t =7.515,P <0.000 1).The tumor involved scope and increased glucose metabolism of lesions did not show any relationship to the levels of serum LDH and CK( P >0.05). Conclusions Muscle lymphoma has distinctive 18 F-FDG uptake,lesion morphology and lesion distribution,which could be differentiated from muscle physiological uptake on PET.Muscle lymphoma does not cause the increase of the levels of serum LDH and CK.