Ablation of Kidney Tumors

Highly localized, efficient, and rapid photothermal therapy using gold nanobipyramids for liver cancer cells triggered by femtosecond laser

In this study, the photothermal effect and up-conversion florescence imaging effect of gold nanobipyramids in liver cancer cells are investigated theoretically and experimentally to explore the photothermal ablation tumor therapy with higher photothermal conversion efficiency, shorter laser action time, smaller action range and lower laser power. The small-size gold nanobipyramids with good biocompatibility and infrared absorption peak located in the first biological window are synthesized. Femtosecond laser is focused on the nanobipyramids clusters in cells and the cells die after being irradiated for 20 s at a power as low as 3 mW. In contrast, the control cells die after irradiation with 30 mW laser for 3 min. The theoretical simulation results show that: under femtosecond laser irradiation, the local thermal effect of gold nanoclusters is produced in the range of hundreds of square nanometers and the temperature rises by 516 °C in 106 picoseconds. This therapy reduces the treatment time to seconds level, and the treatment range to square micrometer level, the power to milliwatt level. In this treatment, cells die by apoptosis rather than necrosis, which reduces inflammation. This result opens up a new way to develop photothermal ablation therapy with less side effects and more minimally invasive.

Outcomes of Percutaneous Thermal Ablation for Biopsy-Proven T1a Renal Cell Carcinoma in Patients With Other Primary Malignancies

OBJECTIVE. The purpose of this article is to investigate the oncologic effectiveness and survival outcomes of percutaneous image-guided thermal ablation for clinical T1a renal cell carcinoma (RCC) in patients with other primary nonrenal malignancies. MATERIALS AND METHODS. We reviewed records of patients with histologically proven T1a RCC (< 4.0 cm) treated with thermal ablation over a period of 10 years between January 2005 and December 2014. We recorded past or current history of primary malignancy other than RCC, status of the primary malignancy, tumor histology (in remission or under therapy), and whether patient was currently alive or not, and if not, the date and reason of death. Three cohorts were studied: patients with RCC only (group A), patients with RCC and other primary malignancy in remission (group B), and patients with RCC and other primary malignancy under treatment (group C). The Kaplan-Meier product-limit estimator was used to estimate the survival rates. RESULTS. One hundred nine patients met the inclusion criteria (109 lesions, 110 ablation procedures). There were 46, 45, and 18 patients in the A, B, and C groups, respectively. The 5-year survival was 87%, 63%, and 40% for groups A, B, and C, respectively. The local recurrence-free survival for the whole sample was 95% at 3, 5, and 10 years. The disease-free survival was 96%, 93%, and 91% at 3, 5, and 10 years. Although a significant difference is noted between the three cohorts in overall survival (p = .02); for RCC, there were no significance differences in the local recurrence-free, disease-free, metastasis-free, and cancer-specific survivals. In addition, there was no difference in outcomes for patients in group B (in remission) when compared with those in group C (under treatment). CONCLUSION. Thermal ablation is an effective and safe modality of treatment of T1a RCC in patients with other primary malignancies that are in remission or under treatment.

Stereotactic laser ablation of high-grade gliomas

Evolving research has demonstrated that surgical cytoreduction of a high-grade glial neoplasm is an important factor in improving the prognosis of these difficult tumors. Recent advances in intraoperative imaging have spurred the use of stereotactic laser ablation (laser interstitial thermal therapy [LITT]) for intracranial lesions. Among other targets, laser ablation has been used in the focal treatment of high-grade gliomas (HGGs). The revived application of laser ablation for gliomas parallels major advancements in intraoperative adjuvants and groundbreaking molecular advances in neuro-oncology. The authors review the research on stereotactic LITT for the treatment of HGGs and provide a potential management algorithm for HGGs that incorporates LITT in clinical practice.

Radiofrequency Ablation of the Pancreas: Protective Effect of Local Cooling Techniques

Pancreatic carcinoma is one of the commonest malignant diseases today and the majority of patients are suitable for palliative treatment only. Radiofrequency ablation (RFA) has been used extensively for the treatment of solid organ tumors but little is known on the efficacy and safety of pancreatic ablation. To further investigate the safety of pancreatic RFA, 18 pigs had RFA of the pancreas, close to superior mesenteric vein and duodenum. Group A (nine animals) was protected with peripancreatic cool perfusion and Group B (nine animals) with portal vein (PV) intravenous injection of cool saline. Biochemical and histological evidence suggested lateral thermal injury of the duodenal wall and superior mesenteric vein and acute pancreatitis in most animals. However, clinically and at autopsy, Group B animals fared much better. PV thrombosis, hepatic abscess, duodenal perforation, ascites, and extensive pancreatic necrosis were observed in Group A but not in Group B. The present study suggests that PV cool saline perfusion can prevent major complications caused by pancreatic RFA and may be used in combination with other protective techniques in the clinical setting to reduce RFA-associated morbidity.

Magnetic resonance imaging-guided focused laser interstitial thermal therapy for intracranial lesions: single-institution series

BACKGROUND:

Surgical treatments for deep-seated intracranial lesions have been limited by morbidities associated with resection. Real-time magnetic resonance imaging–guided focused laser interstitial thermal therapy (LITT) offers a minimally invasive surgical treatment option for such lesions.

OBJECTIVE:

To review treatments and results of patients treated with LITT for intracranial lesions at Washington University School of Medicine.

METHODS:

In a review of 17 prospectively recruited LITT patients (34-78 years of age; mean, 59 years), we report demographics, treatment details, postoperative imaging characteristics, and peri- and postoperative clinical courses.

RESULTS:

Targets included 11 gliomas, 5 brain metastases, and 1 epilepsy focus. Lesions were lobar (n = 8), thalamic/basal ganglia (n = 5), insular (n = 3), and corpus callosum (n = 1). Mean target volume was 11.6 cm³, and LITT produced 93% target ablation. Patients with superficial lesions had shorter intensive care unit stays. Ten patients experienced no perioperative morbidities. Morbidities included transient aphasia, hemiparesis, hyponatremia, deep venous thrombosis, and fatal meningitis. Postoperative magnetic resonance imaging showed blood products within the lesion surrounded by new thin uniform rim of contrast enhancement and diffusion restriction. In conjunction with other therapies, LITT targets often showed stable or reduced local disease. Epilepsy focus LITT produced seizure freedom at 8 months. Preliminary overall median progression-free survival and survival from LITT in tumor patients were 7.6 and 10.9 months, respectively. However, this small cohort has not been followed for a sufficient length of time, necessitating future outcomes studies.

CONCLUSION:

Early peri- and postoperative clinical data demonstrate that LITT is a safe and viable ablative treatment option for intracranial lesions, and may be considered for select patients.

ABBREVIATION:

LITT, laser interstitial thermal therapy

Magnetic resonance imaging-guided focused laser interstitial thermal therapy for subinsular metastatic adenocarcinoma: technical case report

BACKGROUND AND IMPORTANCE

To describe the novel use of the AutoLITT System (Monteris Medical, Winnipeg, Manitoba, Canada) for focused laser interstitial thermal therapy (LITT) with intraoperative magnetic resonance imaging (MRI) and stereotactic image guidance for the treatment of metastatic adenocarcinoma in the left insula.

CLINICAL PRESENTATION

The patient was a 61-year-old right-handed man with a history of metastatic adenocarcinoma of the colon. He had previously undergone resection of multiple lesions, Gamma Knife radiosurgery, and whole-brain radiation. Despite treatment of a left insular tumor, serial imaging revealed that the lesion continued to enlarge. Given the refractory nature of this tumor to radiation and the deep-seated location, the patient elected to undergo LITT treatment. The center of the lesion and entry point on the scalp were identified with STEALTH (Medtronic, Memphis, Tennessee) image-guided navigation. The AXiiiS Stereotactic Miniframe (Monteris Medical) for the LITT system was secured onto the skull, and a trajectory was defined to achieve access to the centroid of the tumor. After a burr hole was made, a gadolinium template probe was inserted into the AXiiiS base. The trajectory was confirmed via an intraoperative MRI, and the LITT probe driver was attached to the base and CO2-cooled, side-firing laser LITT probe. The laser was activated and thermometry images were obtained. Two trajectories, posteromedial and anterolateral, produced satisfactory tumor ablation.

CONCLUSION

LITT with intraoperative MRI and stereotactic image guidance is a newly available, minimally invasive, and therapeutically viable technique for the treatment of deep seated brain tumors.

Does renal mass ablation provide adequate long-term oncologic control?

Renal ablation (RA) is no longer used exclusively in patients with limited life expectancy. There are few studies reporting a minimum follow-up of 5 years. Biases and discrepancies within the literature are abundant. The outcomes of any series must be interpreted in the context of median follow-up time, reported tumor characteristics, ablation technique and training background of the practitioner, and the definition of tumor recurrence. The long-term oncologic efficacy of radiofrequency ablation (RFA) and cryoablation appear similar, although the percutaneous RFA technique may necessitate reablation in more cases. RA is associated with slightly higher rates of local recurrence compared to surgical excision.