van Ginkel R J, Kole A C, Nieweg O E, Molenaar W M, Pruim J, Koops H S, Vaalburg W, Hoekstra H J
Department of Surgical Oncology, PET Center, Groningen University Hospital, The Netherlands.
J Nucl Med. 1999 Feb;40(2):262-7.
PET with L-[1-11C]-tyrosine (TYR) was investigated in patients undergoing hyperthermic isolated limb perfusion (HILP) with recombinant tumor necrosis factor alpha (rTNF-alpha) and melphalan for locally advanced soft-tissue sarcoma and skin cancer of the lower limb.
Seventeen patients (5 women, 12 men; age range 24-75 y; mean age 52 y) were studied. TYR PET studies were performed before HILP and 2 and 8 wk afterwards. The protein synthesis rates (PSRs) in nanomoles per milliliter per minute were calculated. After final PET studies, tumors were resected and pathologically examined. Patients with pathologically complete responses (pCR) showed no viable tumors after treatment. Those with pathologically partial responses (pPR) showed various amounts of viable tumors in the resected tumor specimens.
Six patients (35%) showed a pCR and 11 patients (65%) showed a pPR. All tumors were depicted as hot spots on PET studies before HILP. The PSR in the pCR group at 2 and 8 wk after perfusion had decreased significantly (P < 0.05) in comparison to the PSR before HILP. A significant difference was found in PSR between the pCR and pPR groups at 2 and at 8 wk (P < 0.05). Median PSR in nonviable tumor tissue was 0.62 and ranged from 0.22 to 0.91. With a threshold PSR of 0.91, sensitivity and specificity of TYR PET were 82% and 100%, respectively. The predictive value of a PSR > 0.91 for having viable tumor after HILP was 100%, whereas the predictive value of a PSR < or = 0.91 for having nonviable tumor tissue after HILP was 75%. The 2 patients in the pPR groups with a PSR < 0.91 showed microscopic islets of tumor cells surrounded by extensive necrosis on pathological examination.
Based on the calculated PSR after HILP, TYR PET gave a good indication of the pathological outcome. Inflammatory tissue after treatment did not interfere with viable tumor on the images, suggesting that it may be worthwhile to pursue TYR PET in other therapy evaluation settings.
对接受重组肿瘤坏死因子α（rTNF-α）和美法仑进行热灌注隔离肢体（HILP）治疗下肢局部晚期软组织肉瘤和皮肤癌的患者，进行了L-[1-11C]-酪氨酸（TYR）PET检查。
研究了17例患者（5例女性，12例男性；年龄范围24 - 75岁；平均年龄52岁）。在HILP治疗前、治疗后2周和8周进行TYR PET检查。计算每分钟每毫升纳摩尔的蛋白质合成率（PSR）。在最后一次PET检查后，切除肿瘤并进行病理检查。病理完全缓解（pCR）的患者治疗后无存活肿瘤。病理部分缓解（pPR）的患者在切除的肿瘤标本中显示有不同数量的存活肿瘤。
6例患者（35%）显示pCR，11例患者（65%）显示pPR。所有肿瘤在HILP治疗前的PET检查中均表现为热点。与HILP治疗前相比，pCR组在灌注后2周和8周时的PSR显著降低（P < 0.05）。在2周和8周时，pCR组和pPR组的PSR存在显著差异（P < 0.05）。无存活肿瘤组织中的PSR中位数为0.62，范围为0.22至0.91。以PSR阈值0.91为标准，TYR PET的敏感性和特异性分别为82%和100%。HILP治疗后PSR > 0.91提示有存活肿瘤的预测价值为100%，而HILP治疗后PSR ≤ 0.91提示有非存活肿瘤组织的预测价值为75%。pPR组中2例PSR < 0.91的患者在病理检查中显示肿瘤细胞微小岛被广泛坏死包围。
基于HILP治疗后计算的PSR，TYR PET能很好地提示病理结果。治疗后的炎症组织在图像上不干扰存活肿瘤，这表明在其他治疗评估环境中进行TYR PET检查可能是值得的。
