Histotripsy - hype or hope? Review of innovation and future implications.

BACKGROUND: Histotripsy is a novel, ultrasound-based ablative technique that was recently approved by the Food and Drug Administration for hepatic targets. It has several promising additional theoretical applications that need to be further investigated. Its basis as a nonthermal cavitational technology presents a unique advantage over existing thermal ablation techniques in maximizing local effects while minimizing adjacent tissue destruction. This review discusses the technical basis and current preclinical and clinical data surrounding histotripsy. METHODS: This was a comprehensive review of the literature surrounding histotripsy and the clinical landscape of existing ablative techniques using the PubMed database. A technical summary of histotripsy's physics and cellular effect was described. Moreover, data from recent clinical trials, including Hope4Liver, and future implications regarding its application in various benign and malignant conditions were discussed. RESULTS: Preclinical data demonstrated the efficacy of histotripsy ablation in various organ systems with minimal tissue destruction when examined at the histologic level. The first prospective clinical trial involving histotripsy in hepatocellular carcinoma and liver metastases, Hope4Liver, demonstrated a primary efficacy of 95.5% with minimal complications (6.8%). This efficacy was replicated in similar trials involving the treatment of benign prostatic hypertrophy. DISCUSSION: In addition to the noninvasive ability to ablate lesions in the liver, histotripsy offers additional therapeutic potential. Early data suggest a potential complementary therapeutic effect when combining histotripsy with existing immunologic therapies because of the technology's theoretical ability to sensitize tumors to adaptive immunity. As with most novel therapies, the effect of histotripsy on the oncologic therapeutic landscape remains uncertain.

Diagnostic Workup and Therapeutic Intervention of Hiatal Hernias Discovered as Incidental Findings on Computed Tomography.

BACKGROUND: Computed tomography imaging routinely detects incidental findings; most research focuses on malignant findings. However, benign diseases such as hiatal hernia also require identification and follow-up. Natural language algorithms can help identify these non-malignant findings. METHODS: Imaging of adult trauma patients from 2010 to 2020 who underwent CT chest/abdomen/pelvis was evaluated using an open-source natural language processor to query for hiatal hernias. Patients who underwent subsequent imaging, endoscopy, fluoroscopy, or operation were retrospectively reviewed. RESULTS: 1087(10.6%) of 10 299 patients had incidental hiatal hernias: 812 small (74.7%) and 275 moderate/large (25.3%). 224 (20.7%) had subsequent imaging or endoscopic evaluation. Compared to those with small hernias, patients with moderate/large hernias were older (66.3 ± 19.4 vs 79.6 ± 12.6 years, P < .001) and predominantly female (403[49.6%] vs 199[72.4%], P < .001). Moderate/large hernias were not more likely to grow (small vs moderate/large: 13[7.6%] vs 8[15.1%], P = .102). Patients with moderate/large hernias were more likely to have an intervention or referral (small vs moderate/large: 6[3.5%] vs 7[13.2%], P = .008). No patients underwent elective or emergent hernia repair. Three patients had surgical referral; however, only one was seen by a surgeon. One patient death was associated with a large hiatal hernia. CONCLUSIONS: We demonstrate a novel utilization of natural language processing to identify patients with incidental hiatal hernia in a large population, and found a 10.6% incidence with only 1.2%. (13/1087) of these receiving a referral for follow-up. While most incidental hiatal hernias are small, moderate/large and symptomatic hernias have high risk of loss-to-follow-up and need referral pipelines to improve patient outcomes.

Hepatocellular-Cholangiocarcinoma Collision Tumors: An Update of Current Management Practices.

Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a rare form of primary hepatic collision tumor, with an incidence ranging from 0.4 to 14.2%. Given the diagnostic challenges and lack of randomized trials, standardized treatment has yet to be established. We aim to review the literature to summarize the diagnosis, molecular characteristics, current treatment modalities, and challenges for cHCC-CC. A literature review was performed using PubMed. We included studies investigating and describing cHCC-CC, focusing on surgical, medical, and radiologic treatments. Overall prognosis is poor, with a 5-year survival rate under 30%. Minor or major hepatectomy with R0 resection is the only curative treatment; however, recurrence is likely (as high as 50% within 5 years). The role of liver transplantation is also highly debated given the biliary nature of these tumors, with cHCC-CC as a relative contraindication for liver transplantation. Although gemcitabine-based treatments had higher progression-free survival over sorafenib, there is no standard chemotherapy regimen. Treatment with gemcitabine and platinum demonstrates improved disease control rates compared to gemcitabine in conjunction with 5-fluorouracil (78.4% verse 38.5% respectively). Additionally, platinum-containing chemotherapy regimens exhibit a higher overall response rate than non-platinum regimens (21.4% verse 7.0% respectively). These molecular-directed therapies have prolonged survival for HCC, but further investigation needs to be done to assess their utility in patients with cHCC-CC. cHCC-CC is a rare and complex subset of primary hepatic neoplasms with a dismal prognosis and unstandardized treatment options. Further trials need to be performed to investigate systemic chemotherapy and immunotherapy options for patients with unresectable disease.

Pediatric Appendicitis Transfers From Adult Centers: Can Alvarado Scores Help Determine Which Patients Need a CT?

BACKGROUND: Acute appendicitis is possible for any pediatric patient with abdominal pain. At our tertiary care center, patients are transferred for surgical management with unnecessary or excessive imaging. We hypothesize that using the Alvarado score (AS) to clinically stage patients will identify patient groups that could be transferred prior to imaging. METHODS: Retrospective review of pediatric patients transferred to our hospital for suspected appendicitis between 11/2020 and 3/2022 was performed. Variables collected included AS, imaging, and pathology. Alvarado score was calculated for each patient, and patients were grouped into low score, intermediate score, and high score groups. Positive predictive values (PPVs) were calculated for patients who underwent CT. RESULTS: 196 patients (age 2-17, 58% male) were transferred with suspected appendicitis. CT was obtained in 67% of patients and was not significantly different between groups. The low-score group (n=35) had a rate of appendicitis of 14% and the PPV of CT was 33%. The intermediate-score group (n = 74) had a rate of appendicitis of 62% and the PPV of CT was 88%. In the high-score group (n = 87), the rate of appendicitis was 92% and PPV of CT was 98%. DISCUSSION: Our data show that patients with low, intermediate, and high AS undergo CT at similar rates. We suggest that patients in the low score and high score groups may not benefit from reflexive CT given the likelihood of appendicitis based on the Alvarado score. We propose that CT in these groups be performed at the discretion of the pediatric center in order to expedite transfer and spare children excess radiation.

The Early Impact of the COVID-19 Pandemic on Lung, Colorectal, and Breast Cancer Screening and Treatment at a Tertiary Cancer Center.

OBJECTIVES: During the coronavirus-19 pandemic, experts recommended delaying routine cancer screening and modifying treatment strategies. We sought to understand the sequalae of these recommendations. MATERIALS AND METHODS: We performed a retrospective single-center analysis of screening, diagnosis, and treatment of lung, colorectal, and breast cancer. Data was collected from our institutional cancer registry. Prepandemic (2016-2019) was compared with pandemic (2020) data. RESULTS: Three thousand three sixty one screening chest computed tomography scans (CTs), 35,917 colonoscopies, and 48,093 screening mammograms were performed. There was no difference in CTs [81.0 (SEM10.0) vs. 65.6 (SEM3.29), P =0.067] or mammograms [1017.0 (SEM171.8) vs. 809.4 (SEM56.41), P =0.177] in 2020 versus prepandemic. There were fewer colonoscopies in 2020 [651.4 (SEM103.5) vs. 758.91 (SEM11.79), P =0.043]. There was a decrease in cancer diagnoses per month in 2020 of lung [22.70 (SEM1.469) vs. 28.75 (SEM0.8216), P =0.003] and breast [38.56 (SEM6.133) vs. 51.82 (SEM1.257), P =0.001], but not colorectal [13.11 (SEM1.467) vs. 15.88 (SEM0.585), P =0.074] cancer. There was no change in stage at presentation for lung ( P =0.717), breast ( P =0.115), or colorectal cancer ( P =0.180). Lung had a shorter time-to-treatment in 2020 [38.92 days (SEM 2.48) vs. 66 (SEM1.46), P =0.002]. CONCLUSIONS: In 2020, there was no difference in screening studies for lung and breast cancer but there was a decrease in new diagnoses. Although there were fewer colonoscopies performed in 2020, there was no change in new colorectal cancer diagnoses. Despite changes in guidelines during the pandemic, the time-to-treatment for lung cancer was shorter and was unchanged for colorectal and breast cancer. These findings highlight the importance of continuing care for a vulnerable patient population despite a pandemic.