Case Report: Longitudinal monitoring of clonal evolution by circulating tumor DNA for resistance to anti-EGFR antibody in a case of metastatic colorectal cancer.

Background: Treatment with anti-EGFR antibody has been shown to prolong survival in patients with RAS wild-type metastatic colorectal cancer (mCRC). However, even patients who initially respond to anti-EGFR antibody therapy, almost without exception, develop resistance to the therapy and then fail to respond. Secondary mutations in the mitogen-activated protein (MAPK) signaling pathway (mainly in NRAS and BRAF) have been implicated in anti-EGFR resistance. However, the process by which resistant clones develop during therapy has not been elucidated, and considerable intrapatient and interpatient heterogeneity exists. Circulating tumor DNA (ctDNA) testing has recently allowed the noninvasive detection of heterogeneous molecular alterations that underlie the evolution of resistance to anti-EGFR. In this report, we describe our observation of genomic alterations in KRAS and NRAS in a patient with acquired resistance to anti-EGFR antibody drugs by tracking clonal evolution using serial ctDNA anaylsis. Case presentation: A 54-year-old woman was initially diagnosed with sigmoid colon cancer with multiple liver metastases. After receiving first-line mFOLFOX + cetuximab, second-line FOLFIRI + ramucirumab, third-line trifluridine/tipiracil + bevacizumab, fourth-line regorafenib, and fifth-line CAPOX + bevacizumab, she was rechallenged with CPT-11 + cetuximab. The best response to anti-EGFR rechallenge therapy was a partial response. RAS in the ctDNA was assessed during treatment. The RAS status changed from wild type to mutant type, back to wild type, and again to mutant type (NRAS/KRAS codon 61) during the course of treatment. Conclusion: In this report, tracking of ctDNA allowed us to describe clonal evolution in a case in which we observed genomic alterations in KRAS and NRAS in a patient who acquired resistance to anti-EGFR antibody drugs during treatment. It is reasonable to consider repeat molecular interrogation during progression in patients with mCRC by using ctDNA analysis, which could help to identify patients who may benefit from a rechallenge strategy.

Hilar/mediastinal and cutaneous drug-induced sarcoidosis-like reaction associated with immune checkpoint inhibitors in metastatic colorectal cancer: a case report.

Background: Immune checkpoint inhibitors (ICIs) are the standard treatment for metastatic colorectal cancer (mCRC) with high microsatellite instability (MSI-H). Among immune-related adverse events (irAEs), drug-induced sarcoidosis-like reactions (DISR) are often difficult to differentiate from cancer progression. Main Body: This is a case of a woman in her mid-60s, with mCRC (RAS wild/BRAF mutant/MSI-H) and abdominal lymph node metastasis, treated with four courses of ipilimumab + nivolumab every 3 weeks, followed by nivolumab every 2 weeks as third-line treatment. After treatment, the original lymph node metastases shrank, but hilar/mediastinal lymph nodes appeared. Endoscopic ultrasound-guided fine-needle aspiration of these lymph nodes revealed multiple epithelioid granulomas without necrosis, indicating a sarcoidosis-like reaction. Fluorodeoxyglucose-positron emission tomography scan showed abnormal subcutaneous accumulation in bilateral forearms and bilateral knee joints. Biopsy of the cutaneous lesions was also performed, which revealed epithelioid granulomas. As the patient had no symptoms in other organs, no specific therapeutic intervention was administered. After the discontinuation of immunotherapy, the sarcoidosis-like reaction regressed without cancer relapse. Conclusions: Clinicians should be aware of the possibility of DISR as an irAE during the ICI treatment of mCRC. In suspected cases of DISR following ICI therapy, it is important to differentiate between cancer progression and DISR through histological diagnosis for the subsequent strategy, as radiological and serological findings are not definitive.

Semi-quantitative evaluation of chest computed tomography for coronavirus disease 2019 in a critical care unit: A case-control study.

The spread of abnormal opacity on chest computed tomography (CT) has been reported as a predictor of coronavirus disease 2019 (COVID-19) severity; however, the relationship between CT findings and prognosis in patients with severe COVID-19 remains unclear. The objective of this study was to evaluate the extent of abnormal opacity on chest CT and its association with prognosis in patients with COVID-19 in a critical care medical center, using a simple semi-quantitative method. This single-center case-control study included patients diagnosed with severe COVID-19 pneumonia who were admitted to a critical care center. The diagnosis of COVID-19 was based on positive results of a reverse transcription polymerase chain reaction test. All patients underwent non-contrast whole-body CT upon admission. Six representative axial chest CT images were selected for each patient to evaluate the extent of lung lesions. The percentage of the area involved in the representative CT images was visually assessed by 2 radiologists and scored on 4-point scale to obtain the bedside CT score, which was compared between patients who survived and those who died using the Mann-Whitney U test. A total of 63 patients were included in this study: 51 survived and 12 died after intensive treatment. The inter-rater reliability of bedside scores between the 2 radiologists was acceptable. The median bedside CT score of the survival group was 12.5 and that of the mortality group was 16.5; the difference between the 2 groups was statistically significant. The degree of opacity can be easily scored using representative CT images in patients with severe COVID-19 pneumonia, without sophisticated software. A greater extent of abnormal opacity is associated with poorer prognosis. Predicting the prognosis of patients with severe COVID-19 could facilitate prompt and appropriate treatment.

Clinical impact of primary tumour location, early tumour shrinkage, and depth of response in the treatment of metastatic colorectal cancer with first-line chemotherapy plus cetuximab or bevacizumab.

The primary tumour location is an important prognostic factor for previously untreated metastatic colorectal cancer (mCRC). However, the predictive efficacies of primary tumour location, early tumour shrinkage (ETS), and depth of response (DpR) on mCRC treatment has not been fully evaluated. This study aimed to investigate the predictive efficacies of these traits in mCRC patients treated with first-line 5-fluorouracil-based chemotherapy plus biologic agents, namely, cetuximab and bevacizumab. This was a retrospective analysis of the medical records of 110 patients with pathology-documented unresectable mCRC. Patients with left-sided mCRC receiving any first-line regimen showed better overall survival (OS) than those with right-sided mCRC [33.3 vs 16.3 months; hazard ratio (HR) 0.44; 95% confidence interval (CI) 0.27-0.74; p < 0.001]. In patients with left-sided tumours, treatment with chemotherapy plus cetuximab yielded longer OS than chemotherapy plus bevacizumab (50.6 vs 27.8 months, HR 0.55; 95% CI 0.32-0.97; p = 0.0378). mCRC patients with ETS and high DpR showed better OS than those lacking ETS and with low DpR (33.5 vs 19.6 months, HR 0.50, 95% CI 0.32-0.79, p = 0.023 and 38.3 vs 19.0 months, HR 0.43, 95% CI 0.28-0.68, p < 0.001, respectively). Moreover, ETS and/or high DpR achieved in patients with right-sided mCRC receiving chemotherapy plus cetuximab were associated with significantly better OS than in those lacking ETS and with low DpR (34.3 vs 10.4 months, HR 0.19, 95% CI 0.04-0.94, p = 0.025 and 34.3 vs 10.4 months, HR 0.19, 95% CI 0.04-0.94, p = 0.0257, respectively). Taken together, our study demonstrates that primary tumour location is not only a well-known prognostic factor but also a relevant predictive factor in patients with mCRC receiving chemotherapy plus cetuximab. Additionally, both ETS and DpR could predict treatment outcomes and also potentially guide cetuximab treatment even in right-sided mCRCs.

A dose-escalation study of docetaxel, oxaliplatin, and S-1 (DOS) as a first-line therapy for patients with unresectable metastatic gastric cancer.

PURPOSE: The aim of this study was to determine the recommended dose (RD) for a docetaxel/oxaliplatin/S-1 (DOS) regimen in patients with unresectable gastric cancer and to preliminarily evaluate its efficacy. METHODS: Previously untreated patients with histologically proven unresectable metastatic gastric cancer were enrolled (n = 16). Docetaxel and oxaliplatin were administered intravenously on day 8 and S-1 was administered orally twice a day on days 1-14. Each cycle was repeated every 3 weeks. Dose-limiting toxicities (DLTs) were evaluated during the first treatment cycle. Three dose escalations of DOS were employed in this study: level 1 (50/100/80 mg/m2), level 2 (50/130/80 mg/m2), and level 3 (60/130/80 mg/m2). RESULTS: According to the 3 + 3 dose-escalating schedule, we determined that the RD and maximum tolerated dose for this regimen were level 1 and level 2, respectively. The DLTs were grade 3 diarrhea and febrile neutropenia. The overall response rate was 78% (7/9) for patients with measurable lesions and consisted of two complete responses and five partial responses. Five patients underwent conversion surgery. The median follow-up time was 19 months with median survival time and progression-free survival being 19.6 months and 7.6 months, respectively. CONCLUSIONS: The results from this study demonstrated the safety and tolerability of DOS in unresectable metastatic gastric cancer patients and revealed promising preliminary efficacy with a high conversion rate. A phase II trial of DOS regimen using the identified RD is ongoing.

[CapeOX Therapy as a Salvage Treatment for Advanced Gastric Cancer Refractory to S-1, Cisplatin, Irinotecan, and Taxanes].

AIM: This study aimed to retrospectively evaluate the efficacy and safety of capecitabine plus oxaliplatin(CapeOX)for heavily pretreated advanced gastric cancer(AGC)refractory to S-1, cisplatin, irinotecan, and taxanes. METHODS: Twelve patients with AGC refractory to S-1, cisplatin, irinotecan, and taxanes were enrolled in this study.Treatment comprised capecitabine(1,000mg/m / 2 twice a day on days 1-14)and oxaliplatin(130mg/m2 on day 1).Cycles were repeated at 3- week intervals. RESULTS: The overall response rate was 16.7%, and the disease control rate at 6 weeks was 75.0%. The progression free survival was 3.1 months, and the overall survival was 8.3 months after initiation of CapeOX therapy. The most common hematological toxicity was grade 3 neutropenia(50%).Peripheral neuropathy of Grade 1 or 2 was found in 50%of cases, but no Grade 3 or 4 neuropathy was found. CONCLUSIONS: CapeOX showed some activities as salvage therapy for heavily pretreated AGC patients.We suggest that CapeOX therapy should be considered a treatment option for pretreated AGC with good performance status.

Clinical features and endoscopic findings in patients with actively bleeding colonic angiodysplasia.

Colonic angiodysplasia (AGD) is an important cause of lower gastrointestinal bleeding. However, most episodes of bleeding from colonic AGD stop spontaneously. To date, few data are available regarding the endoscopic findings of bleeding colonic AGD. In order to clarify the clinical features and endoscopic findings of actively bleeding colonic AGD, we conducted a retrospective study of patients treated with colonoscopy at our hospital. From November 2006 to March 2013 inclusive, 32,586 colonoscopies were performed at this hospital, among which 13 patients with bleeding colonic AGD were enrolled in the current study. The mean age was 84 years (range: 69-90 years). All patients had chronic heart disease and were currently using anticoagulant and/or antiplatelet drugs. Sites of bleeding AGD were localized in the left colon in two patients (15 %) and in the right colon in the remaining patients (85 %). A total of 77 % of the lesions (10/13) were 1-2 mm in size and two lesions were 4 mm in size; only one lesion was larger than 5 mm. Endoscopic treatment resulted in a therapeutic success rate of 100 %, and no recurrence of bleeding was observed in 85 % of the patients (11/13) after treatment. During the study period, two patients presented with bleeding from residual AGD and underwent endoscopic treatment. In the present study, most sites of bleeding colonic AGD were very small, termed "micro-angiodysplasia", and targeted endoscopic treatment for actively bleeding AGD was found to be effective and safe. It is essential that physicians consider the potential for actively bleeding colonic AGD, especially "micro-angiodysplasia", when performing colonoscopy in elderly patients with a history of cardiovascular disease and/or treatment with anticoagulant or antiplatelet therapy.

Perfusion CT is superior to angiography in predicting pancreatic necrosis in patients with severe acute pancreatitis.

BACKGROUND: We performed perfusion computed tomography (P-CT) and angiography of the pancreas in patients with severe acute pancreatitis (SAP) and compared the usefulness of these two methods in predicting the development of pancreatic necrosis. METHODS: We compared P-CT and angiography results taken within 3 days after symptom onset in 21 SAP patients. We divided the pancreas into three areas, the head, body, and tail, and examined each area for perfusion defects (via P-CT) and arterial vasospasms (by angiography). Three weeks later, all patients underwent contrast-enhanced CT to determine whether pancreatic necrosis had developed. RESULTS: Of the 21 SAP patients, 16 exhibited perfusion defects, while 17 proved positive for vasospasms in at least one area. Fourteen patients developed pancreatic necrosis. Of the 63 pancreatic areas from the 21 SAP patients, perfusion defects appeared in 25 areas (39.7%), 24 of which showed vasospasms (96.0%). Angiography showed 33 areas with vasospasms (52.4%), of which 24 showed perfusion defects (72.7%). Of the 25 areas with perfusion defects, 21 developed pancreatic necrosis (84.0%). Of the 33 areas with vasospasms, 21 developed necrosis (63.6%). Pancreatic necrosis developed only in the areas positive both for perfusion defects and for vasospasms. No areas without perfusion defect or vasospasms developed pancreatic necrosis. P-CT predicted the development of pancreatic necrosis with significantly higher accuracy than angiography. CONCLUSION: While both P-CT and angiography are useful in predicting the development of pancreatic necrosis in patients with SAP, P-CT appears to be more accurate for this purpose.

Intravenously administered darbepoetin alfa once a week could maintain hemoglobin level more efficiently than once every 2 weeks in patients on hemodialysis.

BACKGROUND: Darbepoetin alfa, which has a much longer half-life than recombinant human erythropoietin, is used to treat renal anemia. However, there are few reports investigating the efficacy of darbepoetin alfa administered every 2 weeks (Q2W). METHODS: We performed the single-center, prospective, and randomized study in chronic hemodialysis patients. Clinically stable patients on hemodialysis were recruited, and darbepoetin alfa 15-40 microg/week was administered intravenously once a week (QW) to achieve a hemoglobin (Hb) level of 10.5-12.0 g/dl for 8 weeks prior to randomization. The patients were randomly assigned to 2 different dosing frequency groups: once a week (QW) or every 2 weeks (Q2W). We switched to a double dose in the Q2W group. We measured Hb level every 2 weeks and administered darbepoetin alfa to achieve an Hb level of 10.5-11.5 g/dl. The primary endpoints were the weekly dose of darbepoetin alfa administered at week 24. RESULTS: We assigned 19 and 20 patients into QW and Q2W, respectively. There were no significant differences between the groups in Hb, transferrin saturation, ferritin, and weekly dose of darbepoetin alfa at end of the baseline period. There was no significant difference in Hb level at week 24, at which time the weekly dose requirement and dose per dry body weight were much higher in the Q2W than in the QW group. CONCLUSION: Administration of darbepoetin alfa Q2W could maintain Hb level similarly to to that obtained QW, but we did not confirm efficiency at a higher dose requirement or blood pressure elevation.

Administration of alfacalcidol for patients with predialysis chronic kidney disease may reduce cardiovascular disease events.

BACKGROUND: Besides its effect on calcium metabolism, vitamin D may play a part in preventing the onset and progression of cardiovascular disease (CVD) events. Only a few reports on the studies relating to whether vitamin D may reduce CVD events in patients with predialysis chronic kidney disease (CKD) are available, and many ambiguities remain. METHODS: We conducted a retrospective cohort study of 665 patients with predialysis CKD. With log-rank test using the Kaplan-Meyer survival curve, comparison of incidences of CVD events, CVD-related mortality, and all-cause mortality were made between patients in the alfacalcidol treatment group (107 patients) in the predialysis stage to whom alfacalcidol 0.25-0.5 microg/day was orally administered for at least 24 weeks, and patients in the nontreatment group (558 patients) who received no administration of alfacalcidol or other type of activated vitamin D and its analogues. Patients to whom alfacalcidol administration was discontinued within 24 weeks as well as initiation of dialysis of <24 weeks were excluded for this study. Factors relating to CVD events were examined using Cox's proportional hazards analysis. RESULTS: The mean follow-up period was 55.1 +/- 38.9 months in the alfacalcidol treatment group and 41.9 +/- 38.4 months in the nontreatment group. CVD events occurred in 172 patients during the follow-up period, and 74 of those occurred during the predialysis period. In the alfacalcidol treatment group, the incidence of cumulative CVD events was significantly lower. In relation to all-cause deaths and CVD-related deaths, the cumulative mortality rate was significantly lower in the alfacalcidol treatment group during the follow-up period. Throughout the follow-up period, the association between CVD events and alfacalcidol use was detected when adjusted for age, sex, diabetes, hypertension, use of renin-angiotensin system inhibitors, estimated glomerular filtration rate, and albumin and parathyroid hormone. CONCLUSION: These data showed that oral administration of alfacalcidol for predialysis CKD patients was associated with reduced risk for CVD.