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Assesses the use of a soil-land inference model (SoLIM) for soil mapping. Limitations of conventional soil surveys; Development of the SoLIM; Major components of the SoLIM; Comparison of the products derived from the SoLIM with those derived from conventional soil maps; Advantages of the SoLIM over the conventional approach; Application and limitation of the SoLIM.

Targeted therapies have transformed clinical management of advanced biliary tract cancer (BTC). Cell-free DNA (cfDNA) analysis is an attractive approach for cancer genomic profiling that overcomes many limitations of traditional tissue-based analysis. We examined cfDNA as a tool to inform clinical management of patients with advanced BTC and generate novel insights into BTC tumor biology. We analyzed next-generation sequencing data of 2068 cfDNA samples from 1671 patients with advanced BTC generated with Guardant360. We carried out clinical annotation on a multi-institutional subset (n = 225) to assess intra-patient cfDNA–tumor concordance and the association of cfDNA variant allele fraction (VAF) with clinical outcomes. Genetic alterations were detected in cfDNA in 84% of patients, with targetable alterations detected in 44% of patients. Fibroblast growth factor receptor 2 (FGFR2) fusions, isocitrate dehydrogenase 1 (IDH1) mutations, and BRAF V600E were clonal in the majority of cases, affirming these targetable alterations as early driver events in BTC. Concordance between cfDNA and tissue for mutation detection was high for IDH1 mutations (87%) and BRAF V600E (100%), and low for FGFR2 fusions (18%). cfDNA analysis uncovered novel putative mechanisms of resistance to targeted therapies, including mutation of the cysteine residue (FGFR2 C492F) to which covalent FGFR inhibitors bind. High pre-treatment cfDNA VAF was associated with poor prognosis and shorter response to chemotherapy and targeted therapy. Finally, we report the frequency of promising targets in advanced BTC currently under investigation in other advanced solid tumors, including KRAS G12C (1.0%), KRAS G12D (5.1%), PIK3CA mutations (6.8%), and ERBB2 amplifications (4.9%). These findings from the largest and most comprehensive study to date of cfDNA from patients with advanced BTC highlight the utility of cfDNA analysis in current management of this disease. Characterization of oncogenic drivers and mechanisms of therapeutic resistance in this study will inform drug development efforts to reduce mortality for patients with BTC. • Targetable genetic alterations were detected in cfDNA in 44% of patients with advanced BTC. • cfDNA analysis detected IDH1 mutations and BRAF V600E at similar rates to tissue biopsies, but only 18% of FGFR2 fusions. • cfDNA analysis uncovered novel putative mechanisms of resistance to targeted therapies in advanced BTC. • High pre-treatment cfDNA VAF was associated with poor prognosis and shorter response to chemotherapy and targeted therapy. • We provide the frequencies of a compendium of promising targets present in cfDNA in BTC that are under investigation in other solid tumors. [ABSTRACT FROM AUTHOR]

The role of SBRT in the treatment of HCC is not well established. The hypothesis of this study was that overall survival (OS) would improve with SBRT followed by sorafenib (SBRT/S) vs. sorafenib alone (S), in patients with advanced HCC. Eligible patients had new or recurrent HCC, unsuitable for resection, transplant, ablation or TACE, with Zubrod performance status (PS) 0-2, Child-Pugh A, intermediate (B) or advanced (C) Barcelona Clinic Liver Cancer Stage (BCLC), ≤ 5 HCCs, sum of hepatic HCCs ≤ 20 cm, and sum of extrahepatic metastases ≤ 3 cm. Patients were randomized 1:1 to S 400 mg BID vs. SBRT (27.5-50Gy in 5 fractions, with dose individualized based on mean liver dose and other dose constraints) followed by S 200 mg BID then increased to 400 mg BID after 28 days if appropriate. Primary endpoint was OS. Reported secondary endpoints were progression-free survival (PFS), time to progression (TTP), and adverse events (AEs - CTCAEv4). Planned sample size was 292 patients (238 OS events, HR=0.72, 80% power, 1-sided alpha=0.05). Accrual closed early, primarily due to a change in HCC standard of care systemic therapy. Statistics were amended to report data as of 7/1/2022, projecting 155 OS events providing 65% power for the original hypothesis, with the same alpha. OS and PFS were estimated by Kaplan-Meier and arms compared using log-rank test. Cox proportional hazards models were used to analyze treatment effect. TTP was estimated with cumulative incidence and arms compared using Gray's test. Secondary endpoints were tested with 2-sided alpha=0.05. Of 193 patients accrued from April 2013 to March 2021 from 23 sites, 177 eligible patients were randomized to S (n=92) vs. SBRT/S (n=85). Median age was 66 years (27-84); 41% had Hepatitis C and 19% had Hepatitis B or B/C. The majority were stage BCLC C (82%), with macrovascular invasion (74%). 4% had metastases. Median follow-up for all and alive patients was 13.2 and 33.7 months, respectively. With 153 OS events, median OS was improved from 12.3 months (90% CI 10.6, 14.3) with S to 15.8 months (90% CI 11.4-19.2) with SBRT/S (HR=0.77, 1-sided p=0.0554). After adjusting for PS, M stage, Child Pugh A5 vs. 6, and degree of vascular HCC, OS was statistically significantly improved for SBRT/S (HR=0.72, 95% CI 0.52-0.99, 2-sided Cox p=0.042). Median PFS was improved from 5.5 months (95% CI 3.4-6.3) with S to 9.2 months (95% CI 7.5-11.9) with SBRT/S (HR=0.55, 95% CI 0.40-0.75, 2-sided p=0.0001). TTP was also improved with SBRT/S (HR=0.69, 95% CI 0.48-0.998, 2-sided Gray's p=0.034). Treatment-related grade 3+ AEs were not significantly different (S - 42%, SBRT/S - 47%; p=0.52). There was one grade 5 treatment-related AE, in the S arm. Adding SBRT improved OS, PFS, and TTP in patients with advanced HCC, compared to Sorafenib alone, with no significant increase in AEs. [ABSTRACT FROM AUTHOR]

To report the long-term outcomes of a prospective, multi-institutional phase II trial of hypofractionated proton beam therapy for hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). This single-arm, phase II, multi-institutional study enrolled 92 patients with localized, unresectable, biopsy-confirmed HCC or ICC with a Child-Turcotte-Pugh score (CTP) of A or B, and ECOG performance status of 0 to 2, to receive proton radiotherapy to a maximum dose of 67.5 GyRBE in 15 fractions. Overall survival (OS) and progression-free survival (PFS) rates were estimated using the Kaplan-Meier method. The patient characteristics, treatment techniques, and two-year outcomes have been previously reported on the 83 evaluable patients in this trial, including 44 with HCC and 39 with ICC who at that time had a median follow-up of 19.5 months. This updated analysis includes a median follow-up of 60.8 months (range 10.3–121.5) and 45.9 months (range 31.1–49.5) among the survivors with HCC and ICC, respectively. For those with HCC, the 5-year OS rate was 25.9% (95% CI 0.13-0.40), with a median OS of 29.2 months. For those with ICC, the 5-year OS rate was 12.3% (95% CI 0.03–0.27), with a median OS of 20.8 months. The 5-year PFS rate was 23.4% (95% CI 0.092-0.41) in HCC and 11.0% (95% CI 0.030-0.25) in ICC. As previously reported, two patients (6.8%) with HCC recurred locally, both within 2 years of treatment, and there were no further local failures. Among the patients with ICC, only one additional local failure occurred, for a total of 7/39 patients (17.9%), with a median time to recurrence of 26.1 months (range 5.5–42.3 months). All patients with local failure had CTP A scores, with a median tumor size of 5.8 cm (range 3.5–7.6 cm). The median radiation dose received by those who had a local recurrence was 58.0 GyRBE (range 45.0–67.5). Local failures occurred in 12.3% (7/57) of patients who received a BED less than 80.5 Gy and in 7.7% (2/26) of those who received a BED greater than 80.5 Gy. Distant failures, including intrahepatic non-local failures, occurred in 56.8% (25/44) of patients with HCC with a median time to progression of 10.2 months (range 2.7–63.6). In those with ICC, distant failures occurred in 61.5% of patients (24/39), with a median time to progression of 5.8 months (range 0.4–68.4). There were no grade 3 or greater late toxicities, including no late biliary toxicity. Hypofractionated proton beam therapy is associated with durable, high rates of local control for both HCC and ICC, however, distant failures are common and remain a challenge. There were no significant late adverse effects, including no late biliary obstruction. Future strategies to incorporate radiation and systemic therapies, including immunotherapy, should be explored to further improve the long-term outcomes of HCC and ICC. [ABSTRACT FROM AUTHOR]