Percutaneous Interstitial Chemotherapy of a Small Hepatocellular Carcinoma under Ultrasound Guidance

Thermal Lesions Induced by 480 KHz Localized Current Field in Guinea Pig and Pig Liver

We evaluated the type, dimension and histopathological evolution of thermal lesions induced in guinea pig and pig liver by radiofrequency electrode needles at various temperatures for different exposure times. The greatest useful necrosis volume was induced by a needle of 1.1 mm diameter and exposed tip 10 mm long at 90 °C and 120 seconds exposure time. It was an ellipsoid with the biggest diameter of about 14 mm diameter and length of about 18 mm. It seems possible that liver tumors of not more than 20 mm diameter in patients without surgical prospects could be destroyed, ultrasonography guiding the needle into the tumor and using the temperature and exposure time mentioned above.

Ultrasound-Guided Percutaneous Ethanol Injection Protocol to Treat Solid and Mixed Thyroid Nodules

CONTEXT

Ultrasound (US)-guided percutaneous ethanol injection (PEI) has been proposed for treatment of benign thyroid nodules (TNs). However, there is no consensus for the optimal amount of ethanol injection, number of applications, and time to re-evaluation in order to achieve maximum volume reduction with minimum adverse effects.

OBJECTIVE

The purpose of the present study was to analyze the effectiveness of an US-guided PEI protocol to treat solid and mixed TNs based on a new target outcome.

PATIENTS AND METHODS

We performed a prospective study evaluating the results of PEI in 52 patients with benign solid and mixed TNs. The ethanol dose was fixed in 30% of the nodular volume per session. Patients returned 1 month after each session for US re-evaluation. Therapeutic success was defined as volume reduction of at least 30% associated with disappearance of clinical symptoms and a complete esthetic satisfaction reported by the patient.

RESULTS

We performed a mean of 2.8 ± 1.9 PEI sessions, with an average total volume of ethanol injected of 9.1 ± 10.3 ml, and a follow-up time of 10.0 ± 8.7 months. There was a reduction of at least 50% of the initial nodular volume in 33 patients (63.5%). In 11 patients (21.2%), the reduction did not reach 50% (mean reduction of 31 ± 11%), but 6 of them reported esthetically satisfactory results and treatment was stopped. Our therapeutic success rate considering the patients with esthetic improvement was 75%. There were no severe complications.

CONCLUSION

Our protocol is effective and safe to treat solid and mixed benign TNs based on our established outcome.

The advent of ultrasound-guided ablation techniques in nodular thyroid disease: towards a patient-tailored approach

Surgery is the long-established therapeutic option for benign thyroid nodules, which steadily grow and become symptomatic. The cost of thyroid surgery, the risk of temporary or permanent complications, and the effect on quality of life, however, remain relevant concerns. Therefore, various minimally invasive treatments, directed towards office-based management of symptomatic nodules, without requiring general anaesthesia, and with negligible damage to the skin and cervical tissues, have been proposed during the past two decades. Today, ultrasound-guided percutaneous ethanol injection and thermal ablation with laser or radiofrequency have been thoroughly evaluated, and are accessible procedures in specialized centres. In clinical practice, relapsing thyroid cysts are effectively managed with percutaneous ethanol injection treatment, which should be considered therapy of choice. In solid non-functioning thyroid nodules that grow or become symptomatic, trained operators may safely induce, with a single session of laser ablation treatment or radiofrequency ablation, a 50% volume decrease and, in parallel, improve local symptoms. In contrast, hyperfunctioning nodules remain best treated with radioactive iodine, which results in a better control of hyperthyroidism, also in the long-term, and fewer side-effects. Currently, minimally invasive treatment is also investigated for achieving local control of small size neck recurrences of papillary thyroid carcinoma in patients who are poor candidates for repeat cervical lymph node dissection. This particular use should still be considered experimental.

Anterior intratumoural chemotherapy: a newer modality of treatment in advanced solid tumours in children

OBJECTIVE

Advanced and inoperable solid tumours in children have high mortality despite aggressive multimodal treatment. Intravenous chemotherapy is abandoned at times because of systemic toxicity. This study investigated intratumoural chemotherapy and compared it with intravenous chemotherapy.

METHODS

Forty children with advanced inoperable solid tumours (Wilms' tumour and neuroblastoma) were randomly allocated into two groups of 20. Group A was given intratumoural chemotherapy and group B was given intravenous chemotherapy. Both groups were compared for reduction in tumour size and volume, tumour resectability, histopathological changes and drug side effects.

RESULTS

Intratumoural chemotherapy was superior to intravenous chemotherapy in terms of reducing tumour size and volume (63% in group A vs. 22% in group B). The resectability was 70% in the intratumoural group compared with 40% in the intravenous group. The overall good histopathological response was 71% in group A as opposed to 0% in group B. Moreover, the incidence and severity of drug side effects and morbidity were less with intratumoural chemotherapy. Mortality was also low in group A (5%) compared to group B (20%).

CONCLUSION

Intratumoural chemotherapy can be offered as an effective and safe alternative treatment modality for advanced and inoperable Wilms' tumour and neuroblastoma.

Non-surgical treatment of hepatocellular carcinoma

A decade ago, surgery was the only satisfactory treatment modality for hepatocellular carcinoma (HCC), but it was limited only to selected cases. For the majority of cases of HCC, systemic chemotherapy was one of the few treatment alternatives, but provided only marginal benefit. In the past 20 years, diagnostic methods have improved to an extent that small HCC less than 1 cm can be detected. Moreover, non-surgical treatment is available, of which regional therapy has been shown to prolong patients' survival, and may even replace surgical resection in some cases. Regional therapy is indicated for the treatment of HCC when there is no extrahepatic metastasis and the patient has adequate liver function reserve, thus permitting repeated therapy. Transcatheter hepatic arterial embolization (TAE) using various embolizers has been well documented to include controlled studies. However, it is not indicated for patients with thrombosed main portal veins. Its therapeutic effect is also doubtful when the tumour is infiltrative in nature or is hypovascular, too large or too small. Additional chemotherapeutic agents mixed into the embolizer with lipiodol and degraded starch microspheres or styrene-maleic acid-neocarzinostatin in which chemotherapeutic agents are embedded, are used with a better response, but the survival rate has not shown significant improvement. Ultrasound-guided local injection therapy is another new method of treatment of HCC. Of these techniques, percutaneous ethanol injection therapy (PEIT) is widely used with excellent results for small, encapsulated tumours in livers with less than three HCC. Percutaneous ethanol injection therapy can also be used in cases with portal vein thrombosis, but it is not suitable for patients having coagulopathy or ascites. Using acetic acid, OK-432, interferon or anti-cancer drugs in the injection therapy shows no further benefit over ethanol alone. Transcatheter echoguided thermotherapy or cryotherapy has been reported in small series of patients, as has target therapy with immune or radiotherapy and conformal radiotherapy. Preliminary studies show encouraging results. Systemic therapy with either single drug or multidrugs is ineffective, with a response rate of less than 20%. Immunotherapy, such as with interferon or other cytokines, is not beneficial. Hormone therapy has not been promising, except for treatment with tamoxifen, which has been reported to show some beneficial effect. Gene therapy is still in its infancy. In summary, recent progress in non-surgical treatment of HCC has resulted in a breakthrough of regional therapy looking quite promising. Moreover, a combination of different types of regional therapies may yield better outcomes in selected individuals.

Estimation of volumes of distribution and intratumoral ethanol concentrations by computed tomography scanning after percutaneous ethanol injection

RATIONALE AND OBJECTIVES

We developed a technique for estimating the volumes of distribution and intratumoral ethanol concentrations using computed tomography (CT) scanning in patients undergoing percutaneous ethanol injection (PEI) treatment of malignant hepatic tumors.

METHODS

A phantom containing anhydrous ethanol diluted with deionized distilled water to concentrations of 0-100% ethanol was scanned by CT. Thirty-seven treatment sessions were performed on eight patients with malignant hepatic tumors undergoing PEI under CT guidance. The patients were scanned pre- and post-PEI, and a region of interest containing the treated hepatic tissue was selected for pixels between -250 and 15 Hounsfield units (H). The mean density of the pixels in this range was computed and the concentration of ethanol estimated. Volumes of distribution of ethanol and intratumoral concentration were then correlated with volume of ethanol injected during PEI. The ratios of volumes of distribution of ethanol to ethanol injected (adjusted in-range [IR]/volume injected) were compared for responders (n = 4) and nonresponders (n = 4).

RESULTS

CT numbers in the phantom scaled linearly with ethanol concentration; 100% ethanol measured -234 H. On CT scans after PEI, the volume of distribution of ethanol correlated positively with the volume injected. Calculated intratumoral ethanol concentrations ranged from 4% to 31%. The adjusted IR/volume injected was significantly higher for responders than nonresponders (p < .5).

CONCLUSION

CT density data can be used to estimate volume of ethanol distribution in tissue; a larger relative intratumoral distribution of alcohol appears to correlate with a favorable response to PEI. However, CT measurement of intratumoral ethanol concentrations may require more complex computational techniques.