A new device for fiducial registration of image-guided navigation system for liver RFA.

PURPOSE: Radiofrequency ablation for liver tumors (liver RFA) is widely performed under ultrasound guidance. However, discriminating between the tumor and the needle is often difficult because of cavitation caused by RFA-induced coagulation. An unclear ultrasound image can lead to complications and tumor residue. Therefore, image-guided navigation systems based on fiducial registration have been developed. Fiducial points are usually set on a patient's skin. But the use of internal fiducial points can improve the accuracy of navigation. In this study, a new device is introduced to use internal fiducial points using 2D US. METHODS: 3D Slicer as the navigation software, Polaris Vicra as the position sensor, and two target tumors in a 3D abdominal phantom as puncture targets were used. Also, a new device that makes it possible to obtain tracking coordinates in the body was invented. First, two-dimensional reslice images from the CT images using 3D Slicer were built. A virtual needle was displayed on the two-dimensional reslice image, reflecting the movement of the actual needle after fiducial registration. A phantom experiment using three sets of fiducial point configurations: one conventional case using only surface points, and two cases in which the center of the target tumor was selected as a fiducial point was performed. For each configuration, one surgeon punctured each target tumor ten times under guidance from the 3D Slicer display. Finally, a statistical analysis examining the puncture error was performed. RESULTS: The puncture error for each target tumor decreased significantly when the center of the target tumor was included as one of the fiducial points, compared with when only surface points were used. CONCLUSION: This study introduces a new device to use internal fiducial points and suggests that the accuracy of image-guided navigation systems for liver RFA can be improved by using the new device.

Cancer treatment and management for elderly patients 80 years of age or older with malignant solid tumors.

OBJECTIVE: We retrospectively analyzed the backgrounds, treatment and nursing care for 96 patients aged 80 years or more with malignant tumors. Twenty of them were hospitalized on an emergency basis. Sixty patients were male and 36 were female, with a median age of 83 years (range: 80-94 years). Twenty-seven had a PS of 3 or 4, and 41 were rated as not independent based on analysis of autonomy at hospitalization. Forty-seven patients had clinical stage III or IV malignancies. The proportions of patients with disease complications were 33.3% for neurological disease, 21.9% for respiratory disease, 70.8% for cardiovascular disease including hypertension, and 36.5% for metabolic disease. Thirty-nine patients underwent surgical or endoscopic resection of their tumors. Twenty-three patients received chemotherapy: hormonal treatment in 14, local injection of cytotoxic agent(s) in 6 and systemic anti-cancer therapy in 3. Thirty-nine patients received supportive care only. Forty-three patients newly required nursing care or an increased level of care at discharge. The median survival time was 10.9 and 15.3 months for stage III/IV and 0/I/II patients, respectively. In conclusion, most elderly patients with malignant tumors require full supportive care, including social nursing care, from the time of cancer diagnosis.

Rate of local tumor progression following radiofrequency ablation of pathologically early hepatocellular carcinoma.

AIM: To evaluate whether pathologically early hepatocellular carcinoma (HCC) exhibited local tumor progression after radiofrequency ablation (RFA) less often than typical HCC. METHODS: Fifty pathologically early HCCs [tumor diameter (mm): mean, 15.8; range, 10-23; follow-up days after RFA: median, 1213; range, 216-2137] and 187 typical HCCs [tumor diameter (mm): mean, 15.6; range, 6-30; follow-up days after RFA: median, 1116; range, 190-2328] were enrolled in this retrospective study. The presence of stromal invasion (namely, tumor cell invasion into the intratumoral portal tracts) was considered to be the most important pathologic finding for the diagnosis of early HCCs. Typical HCC was defined as the presence of a hyper-vascular lesion accompanied by delayed washout using contrast-enhanced computed tomography or contrast-enhanced magnetic resonance imaging. Follow-up examinations were performed at 3-mo intervals to monitor for signs of local tumor progression. The local tumor progression rates of pathologically early HCCs and typical HCCs were then determined using the Kaplan-Meier method. RESULTS: During the follow-up period for the 50 pathologically early HCCs, 49 (98%) of the nodules did not exhibit local tumor progression. However, 1 nodule (2%) was associated with a local tumor progression found 636 d after RFA. For the 187 typical HCCs, 46 (24.6%) of the nodules exhibited local recurrence after RFA. The follow-up period until the local tumor progression of typical HCC was a median of 605 d, ranging from 181 to 1741 d. Among the cases with typical HCCs, local tumor progression had occurred in 7.0% (7/187), 16.0% (30/187), 21.9% (41/187) and 24.6% (46/187) of the cases at 1, 2, 3 and 4 years, respectively. Pathologically early HCC was statistically associated with a lower rate of local tumor progression, compared with typical HCC, when evaluated using a log-rank test (P = 0.002). CONCLUSION: The rate of local tumor progression for pathologically early HCCs after RFA was significantly lower than that for typical HCCs.

Evaluation of hepatocellular carcinoma tumor vascularity using contrast-enhanced ultrasonography as a predictor for local recurrence following radiofrequency ablation.

PURPOSE: The purpose of this study was to evaluate whether the hypervascularity of hepatocellular carcinomas (HCCs) on contrast-enhanced ultrasonography (CEUS) prior to radiofrequency ablation (RFA) is a significant risk factor for local recurrence after RFA. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Overall, 208 patients (mean age, 71.7 years; range, 50-87 years; 137 men, 71 women) with 282 HCCs treated with RFA were analyzed retrospectively. The mean maximum tumor diameter was 15.7mm. We compared the abilities of CEUS and contrast-enhanced computed tomography (CECT) to detect hypervascularity in HCCs. We then classified the HCCs into two groups according to the arterial-phase CEUS findings: a "hypervascular group" with whole or partial hypervascular areas within the lesions compared with the surrounding liver parenchyma, and a "non-hypervascular group" with isovascular or hypovascular areas within the lesions. We assessed the cumulative rate of local recurrence after RFA, and we also evaluated the risk factors for local recurrence using a univariate analysis. RESULTS: The detection rate for hypervascular HCCs was significantly higher using CEUS (78%, 221/282) than that using CECT (66%, 186/282) (P<0.001). Using the CEUS findings, the cumulative rate of local recurrence was significantly higher in the hypervascular group (41.2%, 56/221) than in the non-hypervascular group (18.4%, 6/61) (P=0.007). A univariate analysis revealed that hypervascularity on CEUS was an independent risk factor for local recurrence (P=0.010). CONCLUSION: Hypervascularity in HCCs as observed using CEUS is a significant risk factor for local recurrence after RFA.

Peritoneal sarcoidosis:an unusual cause of ascites.

An 83-year-old male presented with distended abdomen. A computed tomography scan demonstrated pleural effusion, ascites, peritoneal thickness, and panniculitis. Multiple small white nodules of peritoneum were observed during a laparoscopy examination, and biopsy specimens revealed noncaseating granulomas. Gallium scintigram demonstrated an accumulation in the peritoneum and revealed a panda sign that has been described as an indication of sarcoidosis. Although sarcoidosis rarely induces peritonitis with ascites, peritoneal sarcoidosis was diagnosed and he began receiving steroid therapy. After primary steroid therapy, his ascites completely disappeared, and he has maintained a complete response with continuous low dose steroid therapy.