Can Imaging Using Radiomics and Fat Fraction Analysis Detect Early Tissue Changes on Historical CT Scans in the Regions of the Pancreas Gland That Subsequently Develop Adenocarcinoma?

Despite a growing number of effective therapeutic options for patients with pancreatic adenocarcinoma, the prognosis remains dismal mostly due to the late-stage presentation and spread of the cancer to other organs. Because a genomic analysis of pancreas tissue revealed that it may take years, if not decades, for pancreatic cancer to develop, we performed radiomics and fat fraction analysis on contrast-enhanced CT (CECT) scans of patients with historical scans showing no evidence of cancer but who subsequently went on to develop pancreas cancer years later, in an attempt to identify specific imaging features of the normal pancreas that may portend the subsequent development of the cancer. In this IRB-exempt, retrospective, single institution study, CECT chest, abdomen, and pelvis (CAP) scans of 22 patients who had evaluable historical imaging data were analyzed. The images from the "healthy" pancreas were obtained between 3.8 and 13.9 years before the diagnosis of pancreas cancer was established. Afterwards, the images were used to divide and draw seven regions of interest (ROIs) around the pancreas (uncinate, head, neck-genu, body (proximal, middle, and distal) and tail). Radiomic analysis on these pancreatic ROIs consisted of first order quantitative texture analysis features such as kurtosis, skewness, and fat quantification. Of all the variables tested, fat fraction in the pancreas tail (p = 0.029) and asymmetry of the histogram frequency curve (skewness) of pancreas tissue (p = 0.038) were identified as the most important imaging signatures for subsequent cancer development. Changes in the texture of the pancreas as measured on the CECT of patients who developed pancreas cancer years later could be identified, confirming the utility of radiomics-based imaging as a potential predictor of oncologic outcomes. Such findings may be potentially useful in the future to screen patients for pancreatic cancer, thereby helping detect pancreas cancer at an early stage and improving survival.

Early response of hepatic malignancies to locoregional therapy-value of diffusion-weighted magnetic resonance imaging and proton magnetic resonance spectroscopy.

PURPOSE: The objective of our study was to determine the usefulness of the diffusion-weighted magnetic resonance imaging and proton magnetic resonance spectroscopy (H-MRS) of hepatic malignancies for the assessment of response to locoregional treatment. METHODS: Forty-four patients (29 men; mean age, 58 years) with hepatic malignancies were treated locally. Magnetic resonance imaging examinations obtained before and at 1 and 6 months after transarterial chemoembolization were analyzed retrospectively. Imaging criteria included change in tumor size, percentage of enhancement in the arterial and portal venous phases, diffusion-weighted magnetic resonance imaging apparent diffusion coefficients, and choline concentration by quantitative H-MRS. Response to treatment was grouped according to RECIST (Response Evaluation Criteria in Solid Tumors) and European Association for the Study of the Liver (EASL) criteria based on magnetic resonance imaging at 6 months after treatment. Statistical analysis used paired t test, Fisher exact test, and univariate and multivariate Cox proportional hazards models. RESULTS: Before treatment, the median tumor diameter was 6 cm; at 6 months after treatment, median tumor diameter was 5.1 cm. According to RECIST and EASL, 66% of the patients achieved partial response, 31% had stable disease, and 3% of the patients showed progressive disease. One month after transarterial chemoembolization, apparent diffusion coefficient increased (P < 0.14), and mean choline concentration of the tumors decreased (P < 0.008). CONCLUSIONS: Diffusion-weighted imaging and hepatic choline levels by H-MRS could predict response to locoregional therapy.

Current approaches to the treatment of early hepatocellular carcinoma.

For patients with early-stage hepatocellular carcinoma (HCC), potentially curative treatment options exist, including liver transplantation, surgical resection, and ablation therapy. These treatments are associated with survival benefits, and outcomes are optimized by identification of appropriate patients. However, further studies are needed to definitively confirm optimal treatment approaches for all patients. Treatment patterns vary in different parts of the world as a result of geographic differences in the incidence and presentation of the disease. In particular, because of successful screening programs, a high proportion of tumors that are identified in Japan are amenable to curative treatments, which are appropriate in a smaller proportion of patients in the west, although screening is now widely carried out in industrialized countries. Differences in the applicability of transplantation are also evident between the west and Asia. Although existing treatments for early-stage HCC are supported by considerable evidence, there remain significant data gaps. For example, further data, ideally from randomized controlled trials, are needed regarding: the use of neoadjuvant and adjuvant therapy to decrease the rate of recurrence after resection or ablation, further investigation of the role of chemoprevention following resection, and prospective analysis of outcomes of living donor compared with deceased donor liver transplantation.

Pulmonary embolization of bovine collagen.

A bovine collagen matrix is sometimes used as a delivery medium during direct intratumoral injection of a chemotherapeutic agent. The bovine collagen enhances the dose and duration of local drug delivery and limits systemic toxicity. Although this strategy is advocated as a means of easy and effective delivery of chemotherapeutic drugs, the associated risks are not well defined. We report the case of a 71-year-old man with hepatocellular carcinoma who underwent weekly intratumoral injections of cisplatin in a bovine collagen matrix. During the third injection, he suddenly and unexpectedly underwent cardiac arrest and died. An autopsy disclosed diffuse occlusion of the pulmonary microcirculation by bovine collagen. The collagen emboli were associated with an inflammatory infiltrate typical of bovine collagen-induced hypersensitivity. This case identifies a fatal complication of intratumoral chemotherapy injections using a bovine collagen matrix, which does not appear to have been previously reported. This case underscores the valuable role of the traditional autopsy examination as a means of identifying possible complications of novel oncologic strategies, which are being rapidly developed and implemented.