Bjorkman D J, Samowitz W S, Brigham E J, Peterson B J, Straight R C
Utah Laser Institute, Veterans Administration Medical Center, Salt Lake City.
Lasers Surg Med. 1991;11(3):263-70. doi: 10.1002/lsm.1900110310.
Laser excitation of hematoporphyrin derivatives (HPD) localizing in tumors of the tracheobronchial tree and bladder is useful in the identification and treatment of those tumors. A comparable utility for HPD in the endoscopic localization of colonic tumors may be possible. In this study the ability of HPD to identify 1,2 dimethylhydrazine (DMH) induced colon cancer in rats is evaluated. A total of 111 rats were studied with HPD. Sixty-nine rats received weekly injections of DMH (20 mg/kg) and 42 received injections of the vehicle alone. Twenty-four hours after the intravenous injection of 5 mg/kg of HPD, 18 DMH-induced tumors were identified by visual fluorescence using excitation by either a blue light (390-436 nm) or an argon laser (488 and 514 nm). This represented 100% of the visually or microscopically detected tumors. Seventy-five fluorescent areas were noted that did not contain evidence of cancer. The majority (63) of false positive areas contained lymphoid follicles. All but 2 false positive areas (73/75, 97%, p less than .001) were seen in DMH-treated animals, suggesting that they were an artifact of DMH treatment. HPD fluorescence did not identify microscopic dysplasia. We conclude that HPD fluorescence is an effective method of identifying early colonic cancer and may have a potential clinical role in patients at high risk for colorectal cancer.
激光激发定位在气管支气管树和膀胱肿瘤中的血卟啉衍生物（HPD），对于这些肿瘤的识别和治疗很有用。HPD在结肠肿瘤的内镜定位中可能也有类似的用途。在本研究中，评估了HPD识别1,2-二甲基肼（DMH）诱导的大鼠结肠癌的能力。共有111只大鼠接受了HPD研究。69只大鼠每周注射DMH（20mg/kg），42只仅注射赋形剂。静脉注射5mg/kg的HPD后24小时，通过蓝光（390 - 436nm）或氩激光（488和514nm）激发产生的视觉荧光识别出18个DMH诱导的肿瘤。这代表了肉眼或显微镜下检测到的肿瘤的100%。发现75个荧光区域没有癌症证据。大多数（63个）假阳性区域含有淋巴滤泡。除2个假阳性区域外（73/75，97%，p小于0.001），所有假阳性区域均见于DMH治疗的动物，提示它们是DMH治疗的一种假象。HPD荧光未识别出显微镜下的发育异常。我们得出结论，HPD荧光是识别早期结肠癌的有效方法，可能在结直肠癌高危患者中具有潜在的临床作用。
