Microwave versus radiofrequency ablation for the treatment of liver malignancies: a randomized controlled phase 2 trial

Microwave (MWA) and radiofrequency ablation (RFA) are main ablative techniques for hepatocellular carcinoma (HCC) and colorectal liver metastasis (MT). This randomized phase 2 clinical trial compares the effectiveness of MWA and RFA as well as morphology of corresponding ablation zones. HCC and MT patients with 1.5–4 cm tumors, suitable for ablation, were randomized into MWA or RFA Groups. The primary endpoint was short-to-long diameter ratio of ablation zone (SLR). Primary technical success (TS) and a cumulative local tumor progression (LTP) after a median 2-year follow-up were compared. Between June 2015 and April 2020, 82 patients were randomly assigned (41 patients per group). For the per-protocol analysis, five patients were excluded. MWA created larger ablation zones than RFA (p = 0.036) although without differences in SLR (0.5 for both groups, p = 0.229). The TS was achieved in 98% (46/47) and 90% (45/50) (p = 0.108), and LTP was observed in 21% (10/47) vs. 12% (6/50) (OR 1.9 [95% CI 0.66–5.3], p = 0.238) of tumors in MWA vs. RFA Group, respectively. Major complications were found in 5 cases (11%) vs. 2 cases (4%), without statistical significance. MWA and RFA show similar SLR, effectiveness and safety in liver tumors between 1.5 and 4 cm.

Percutaneous Image-Guided Ablation of Lung Tumors

Tumors of the lung, including primary cancer and metastases, are notoriously common and difficult to treat. Although surgical resection of lung lesions is often indicated, many conditions disqualify patients from being surgical candidates. Percutaneous image-guided lung ablation is a relatively new set of techniques that offers a promising treatment option for a variety of lung tumors. Although there have been no clinical trials to definitively compare its efficacy to those of traditional treatments, lung ablation is widely practiced and generally accepted to be safe and effective. Especially encouraging results have recently emerged for cryoablation, one of the newer ablative techniques. This article reviews the indications, techniques, contraindications, and complications of percutaneous image-guided ablation of lung tumors with special attention to cryoablation and its recent developments in protocol optimization.

Advanced Endoscopic Imaging and Interventions in GERD: An Update and Future Directions

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal diseases encountered in primary care and gastroenterology clinics. Most cases of GERD can be diagnosed based on clinical presentation and risk factors; however, some patients present with atypical symptoms, which can make diagnosis difficult. An esophagogastroduodenoscopy can be used to assist in diagnosis of GERD, though only half of these patients have visible endoscopic findings on standard white light endoscopy. This led to the development of new advanced endoscopic techniques that enhanced the diagnosis of GERD and related complications like squamous cell dysplasia, Barrett's esophagus, and early esophageal adenocarcinoma. This is conducted by improved detection of subtle irregularities in the mucosa and vascular structures through optical biopsies in real-time. Management of GERD includes lifestyle modifications, pharmacological therapy, endoscopic and surgical intervention. Minimally invasive endoscopic intervention can be an option in selected patients with small hiatal hernia and without complications of GERD. These endoscopic interventions include endoscopic fundoplication, endoscopic mucosal resection techniques, ablative techniques, creating mechanical barriers, and suturing and stapling devices. As these new advanced endoscopic techniques are emerging, data surrounding the indications, advantages and disadvantages of these techniques need a thorough understanding.

Non-Melanoma Skin Cancer in People Living With HIV: From Epidemiology to Clinical Management

Skin cancers represent the most common human tumors with a worldwide increasing incidence. They can be divided into melanoma and non-melanoma skin cancers (NMSCs). NMSCs include mainly squamous cell (SCC) and basal cell carcinoma (BCC) with the latest representing the 80% of the diagnosed NMSCs. The pathogenesis of NMSCs is clearly multifactorial. A growing body of literature underlies a crucial correlation between skin cancer, chronic inflammation and immunodeficiency. Intensity and duration of immunodeficiency plays an important role. In immunocompromised patients the incidence of more malignant forms or the development of multiple tumors seems to be higher than among immunocompetent patients. With regards to people living with HIV (PLWH), since the advent of combined antiretroviral therapy (cART), the incidence of non-AIDS-defining cancers (NADCs), such as NMSCs, have been increasing and now these neoplasms represent a leading cause of illness in this particular population. PLWH with NMSCs tend to be younger, to have a higher risk of local recurrence and to have an overall poorer outcome. NMSCs show an indolent clinical course if diagnosed and treated in an early stage. BCC rarely metastasizes, while SCC presents a 4% annual incidence of metastasis. Nevertheless, metastatic forms lead to poor patient outcome. NMSCs are often treated with full thickness treatments (surgical excision, Mohs micro-graphic surgery and radiotherapy) or superficial ablative techniques (such as cryotherapy, electrodesiccation and curettage). Advances in genetic landscape understanding of NMSCs have favored the establishment of novel therapeutic strategies. Concerning the therapeutic evaluation of PLWH, it’s mandatory to evaluate the risk of interactions between cART and other treatments, particularly antiblastic chemotherapy, targeted therapy and immunotherapy. Development of further treatment options for NMSCs in PLWH seems needed. We reviewed the literature after searching for clinical trials, case series, clinical cases and available databases in Embase and Pubmed. We review the incidence of NMSCs among PLWH, focusing our attention on any differences in clinicopathological features of BCC and SCC between PLWH and HIV negative persons, as well as on any differences in efficacy and safety of treatments and response to immunomodulators and finally on any differences in rates of metastatic disease and outcomes.

An Update on Hepatocellular Carcinoma in Chronic Kidney Disease

Chronic kidney disease is a major public health issue globally and the risk of cancer (including HCC) is greater in patients on long-term dialysis and kidney transplant compared with the general population. According to an international study on 831,804 patients on long-term dialysis, the standardized incidence ratio for liver cancer was 1.2 (95% CI, 1.0–1.4) and 1.5 (95% CI, 1.3–1.7) in European and USA cohorts, respectively. It appears that important predictors of HCC in dialysis population are hepatotropic viruses (HBV and HCV) and cirrhosis. 1-, 3-, and 5-year survival rates are lower in HCC patients on long-term dialysis than those with HCC and intact kidneys. NAFLD is a metabolic disease with increasing prevalence worldwide and recent evidence shows that it is an important cause of liver-related and extra liver-related diseases (including HCC and CKD, respectively). Some longitudinal studies have shown that patients with chronic hepatitis B are aging and the frequency of comorbidities (such as HCC and CKD) is increasing over time in these patients; it has been suggested to connect these patients to an appropriate care earlier. Antiviral therapy of HBV and HCV plays a pivotal role in the management of HCC in CKD and some combinations of DAAs (elbasvir/grazoprevir, glecaprevir/pibrentasvir, sofosbuvir-based regimens) are now available for HCV positive patients and advanced chronic kidney disease. The interventional management of HCC includes liver resection. Some ablative techniques have been suggested for HCC in CKD patients who are not appropriate candidates to surgery. Transcatheter arterial chemoembolization has been proposed for HCC in patients who are not candidates to liver surgery due to comorbidities. The gold standard for early-stage HCC in patients with chronic liver disease and/or cirrhosis is still liver transplant.

Laser Resurfacing Monotherapy for the Treatment of Actinic Keratosis

Treating actinic keratosis (AK) and photodamaged skin is critical to reduce the risk of progression to skin cancer. Laser resurfacing for AK treatment is available as either lesion-directed or field therapy. Laser resurfacing removes the superficial epidermis and dermis containing actinic damage, promoting re-epithelialization of healthy skin. Although laser resurfacing has been explored as a modality for AK treatment in the literature, studies summarizing its efficacy in the treatment of AK are lacking. This review summarizes existing research on laser resurfacing as a monotherapy for AK treatment, highlighting the various laser resurfacing modalities available for AK treatment as well as their complications and efficacy in comparison to other therapies. Despite longer healing time, fully ablative laser resurfacing, including carbon dioxide and erbium-doped yttrium aluminum garnet were found to be more effective for AK treatment than fractional ablative techniques. Although some studies suggest laser resurfacing monotherapy as less efficacious than photodynamic therapy, and equally effective to 5-fluorouracil and 30% trichloroacetic acid, clinical trials of larger sample size are required to establish stronger evidence-based conclusions. Moreover, laser resurfacing used as lesion-directed therapy, as opposed to the usual field-therapy, requires further investigation.

Update of Radiofrequency Ablation for Treating Benign and Malignant Thyroid Nodules. The Future Is Now

Thermal and chemical ablation are minimally invasive procedures that avoid removal of the thyroid gland and target symptomatic nodules directly. Internationally, Radiofrequency ablation (RFA) is among one of the most widely used thermal ablative techniques, and is gaining traction in North America. Surgery remains the standard of care for most thyroid cancer, and in the right clinical setting, Active Surveillance (AS) can be a reasonable option for low risk disease. Minimally invasive techniques have emerged as an alternative option for patients deemed high risk for surgery, or for those patients who wish to receive a more active treatment approach compared to AS. Herein, we review the literature on the safety and efficacy of RFA for treating benign non-functioning thyroid nodules, autonomously functioning thyroid nodules, primary small low risk thyroid cancer (namely papillary thyroid cancer) as well as recurrent thyroid cancer.

Measurement of Ex Vivo Liver, Brain and Pancreas Thermal Properties as Function of Temperature

The ability to predict heat transfer during hyperthermal and ablative techniques for cancer treatment relies on understanding the thermal properties of biological tissue. In this work, the thermal properties of ex vivo liver, pancreas and brain tissues are reported as a function of temperature. The thermal diffusivity, thermal conductivity and volumetric heat capacity of these tissues were measured in the temperature range from 22 to around 97 °C. Concerning the pancreas, a phase change occurred around 45 °C; therefore, its thermal properties were investigated only until this temperature. Results indicate that the thermal properties of the liver and brain have a non-linear relationship with temperature in the investigated range. In these tissues, the thermal properties were almost constant until 60 to 70 °C and then gradually changed until 92 °C. In particular, the thermal conductivity increased by 100% for the brain and 60% for the liver up to 92 °C, while thermal diffusivity increased by 90% and 40%, respectively. However, the heat capacity did not significantly change in this temperature range. The thermal conductivity and thermal diffusivity were dramatically increased from 92 to 97 °C, which seems to be due to water vaporization and state transition in the tissues. Moreover, the measurement uncertainty, determined at each temperature, increased after 92 °C. In the temperature range of 22 to 45 °C, the thermal properties of pancreatic tissue did not change significantly, in accordance with the results for the brain and liver. For the three tissues, the best fit curves are provided with regression analysis based on measured data to predict the tissue thermal behavior. These curves describe the temperature dependency of tissue thermal properties in a temperature range relevant for hyperthermia and ablation treatments and may help in constructing more accurate models of bioheat transfer for optimization and pre-planning of thermal procedures.