Evaluation of intrahepatic perfusion on fusion imaging using a combined CT/SPECT system: influence of anatomic variations on hemodynamic modification before installation of implantable port systems for hepatic arterial infusion chemotherapy.

BACKGROUND: In some patients with hepatic tumors, anatomic variations in the hepatic arteries may require hemodynamic modification to render effective hepatic arterial infusion chemotherapy delivered via implantable port systems. We used a combined CT/SPECT system to obtain fused images of the intrahepatic perfusion patterns in patients with such anatomic variations and assessed their effects on the treatment response of hepatic tumors. METHODS: Using a combined SPECT/CT system, we obtained fused images in 110 patients with malignant liver tumors (n = 75) or liver metastasis from unresectable pancreatic cancer (n = 35). Patients with anatomic hepatic arteries variations underwent hemodynamic modification before the placement of implantable port systems for hepatic arterial infusion chemotherapy. We evaluated their intrahepatic perfusion patterns and the initial treatment response of their liver tumors. The perfusion patterns on the fused images were classified as homogeneous, local hypoperfusion, and/or perfusion defect. Using the WHO criteria of complete response (CR), partial response (PR), no change (NC), and progressive disease (PD), we evaluated the patients' tumor responses after 3 months on multislice helical CT scans. The treatment was regarded as effective in patients who achieved a complete response or partial response. RESULTS: Anatomic hepatic artery variations were present in 15 of the 110 patients (13.6%); 5 manifested replacement of the left hepatic artery (LHA), 8 of the right hepatic artery (RHA), and 1 each had replacement of the RHA and LHA, and replacement of the LHA plus an accessory RHA. In 13 of these 15 patients (87%), occlusion with metallic coils was successful. On fusion imaging, the perfusion patterns were recorded as homogeneous in 6 patients (43%), as hypoperfusion in 7 (50%), and 1 patient had a perfusion defect (7.1%) in the embolized arterial region. Of the 8 patients with RHA replacement, 4 manifested a homogeneous distribution and 3 hypoperfusion. In 2 of 5 patients with LHA replacement, the distribution was homogeneous. In 1 patient with RHA and LHA replacement, and in 1 patient with LHA replacement and an accessory RHA, we noted hypoperfusion in the RHA territory. All 6 patients with homogeneous distribution were classified as PR or NC on follow-up multidetector CT. Of the 7 patients manifesting hypoperfusion, 3 were classified as PD (43%), 3 as NC (43%), and 1 as PR (14%) on follow-up CT. CONCLUSION: Hemodynamic modification of anatomic hepatic artery variations resulted in hypoperfusion on fusion images. Differences in the intrahepatic perfusion patterns may affect the response to hepatic arterial infusion chemotherapy.

Evaluation of extrahepatic perfusion of anticancer drugs in the right gastric arterial region on fused images using combined CT/SPECT: is extrahepatic perfusion predictive of gastric toxicity?

BACKGROUND: Hepatic arterial infusion (HAI) chemotherapy is effective for treating primary and metastatic carcinomas of the liver. Since hepatic arteries also supply the stomach and duodenum, HAI may result in unwanted infusion into the upper gastrointestinal tract and consequent gastric toxicity. Using fused images obtained with a combined SPECT/CT system, we assessed extrahepatic perfusion (EHP) and its correlation with gastrointestinal toxicity in patients receiving HAI. METHODS: We studied 41 patients with primary or metastatic carcinoma of the liver who received HAI chemotherapy consisting of 5-fluorouracil and cisplatin. All underwent abdominal SPECT using a (99m)Tc-MAA (185 MBq) instrument and an injection rate of 0.1 ml/min, identical to the chemotherapy infusion rate. Delivery was through an implantable port. We analyzed the distribution of the anticancer agent on fused images and the relationship between EHP of the right gastric arterial region and gastric toxicity. All patients underwent esophagogastroduodenoscopy (EGDS). RESULTS: Of the 41 patients, 11 (27%) manifested enhancement of the duodenal and gastric pyloric region on fused images. EGDS at the time of reservoir placement detected gastric ulcers in 10 of these patients. CONCLUSION: Fusion imaging with combined SPECT/CT reflects the actual distribution of the infused anticancer agents. The detection of EHP on fused images is predictive of the direct gastric toxicity from anticancer agents in patients undergoing HAI.

[Local ablation therapy for hepatocellular carcinoma (HCC) on the liver surface: radio-frequency ablation aimed at tumor marginal pre-ablation under endoscopic surgery].

RFA for the hepatocellular carcinoma localized on the surface of the liver tends to have some complications such as bleeding, an ejection of tumor and a heat injury to other internal organs even if percutaneous RFA seemed to be done easily. Therefore, we should first choose the RFA treatment under endoscopic (either laparoscope or thoracoscope) surgery for the hepatocellular carcinoma localized on the surface of the liver. Moreover, a direct central puncture should be avoided from the viewpoint of securing a margin, prevention of bleeding and rise in the intratumorale pressure. Now, we selected the unique operation method of RFA: First, the tumor is confirmed under the endoscope, and the tumor range is marked with the endoscopic echo. Second, several times of RFA applied to the tumor surroundings are done, and the margin is secured with avoiding a direct central puncture. If tumor diameter is over 2.5 cm, central ablation of the tumor is considered to be necessary, we can directly puncture the center of the tumor without bleeding since the tumor already has the congelation by surrounding heat effect. We have done RFA by this way for 29 patients with HCC since April 1st, 2004. The complications such as a heat injury to the neighboring organ could be well prevented. An enough margin of ablation about 1 cm around the tumor was confirmed by the postoperative CT image. There was no local recurrence during the average observation period of 290 days, and a severe post operative complication has not occurred. The average of hospitalized period after the operation was about 10 days. Therefore, pre-surrounding ablation preceding central puncture under the endosope for hepatocellular carcinoma on the liver surface is a feasible technique.