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1.
Lessons Learned
  • Panitumumab monotherapy showed favorable efficacy and feasibility in the treatment of frail or elderly patients with RAS wild‐type unresectable colorectal cancer.
  • It is especially effective for left‐sided tumors; therefore, panitumumab as first‐line treatment could be an additional therapeutic option for frail elderly patients, particularly in those who are unsuitable for upfront oxaliplatin‐based or irinotecan‐based combination regimens.
BackgroundFirst‐line panitumumab monotherapy is expected to be well tolerated and improve survival in patients ineligible for intensive chemotherapy. However, its safety and efficacy in chemotherapy‐naïve frail or elderly patients with unresectable RAS wild‐type (WT) colorectal cancer (CRC) have not been studied. The aim of this phase II trial was to evaluate the efficacy and safety of panitumumab as first‐line treatment.MethodsWe conducted a multicenter phase II study on patients aged ≥76 years or ≥65 years considered unsuitable for intensive chemotherapy. Panitumumab 6 mg/kg of intravenous infusion was administered every 2 weeks. The primary endpoint was disease control rate (DCR). Secondary endpoints included progression‐free survival (PFS), overall survival (OS), response rate (RR), time to treatment failure (TTF), and incidence of grade 3 or 4 toxicities.ResultsThirty‐six patients (median age: 81 [range, 67–88] years) were enrolled between February 2017 and August 2018. Two patients were excluded from the analysis of efficacy: one from lack of image examination at baseline and the other from lack of a measurable lesion. Thirty‐three (91.6%) patients had a performance status (PS) of 0 or 1, whereas two (5.6%) patients and one (2.8%) patient had a PS of 2 and 3, respectively. Twenty‐eight patients (77.8%) had left‐sided CRC, whereas eight (22.2%) had right‐sided CRC. The RR was 50.0% (95% confidence interval [CI], 32.4–67.6), including three patients (8.8%) who had complete responses. A total of 26.5% had stable diseases, resulting in a DCR of 76.5% (90% CI, 61.5–87.7). The RR of patients with left‐ and right‐sided tumors was 65.4% (95% CI, 44.3–82.8) and 0.0% (95% CI, 0.0–36.9), respectively. Major grade 3 or 4 nonhematologic toxicities were rash (n = 6, 16.7%), hypomagnesemia (n = 4, 11.1%), fatigue (n = 3, 8.3%), paronychia (n = 2, 5.6%), and hyponatremia (n = 2, 5.6%). The only grade 3 hematologic toxicity was neutropenia (n = 1, 2.8%).ConclusionPanitumumab monotherapy showed favorable efficacy and feasibility in frail or elderly patients with RAS WT unresectable CRC. Survival analysis including OS, PFS, and TTF is currently in progress.  相似文献   
2.
The WJOG8815L phase II clinical study involves patients with non‐small cell lung cancer (NSCLC) that harbored the EGFR T790M mutation, which confers resistance to EGFR tyrosine kinase inhibitors (TKIs). The purpose of this study was to assess the predictive value of monitoring EGFR genomic alterations in circulating tumor DNA (ctDNA) from patients with NSCLC that undergo treatment with the third‐generation EGFR‐TKI osimertinib. Plasma samples of 52 patients harboring the EGFR T790M mutation were obtained pretreatment (Pre), on day 1 of treatment cycle 4 (C4) or cycle 9 (C9), and at diagnosis of disease progression or treatment discontinuation (PD/stop). CtDNA was screened for EGFR‐TKI‐sensitizing mutations, the EGFR T790M mutation, and other genomic alterations using the cobas EGFR Mutation Test v2 (cobas), droplet digital PCR (ddPCR), and targeted deep sequencing. Analysis of the sensitizing—and T790M—EGFR mutant fractions (MFs) was used to determine tumor mutational burden. Both MFs were found to decrease during treatment, whereas rebound of the sensitizing EGFR MF was observed at PD/stop, suggesting that osimertinib targeted both T790M mutation‐positive tumors and tumors with sensitizing EGFR mutations. Significant differences in the response rates and progression‐free survival were observed between the sensitizing EGFR MF‐high and sensitizing EGFR MF‐low groups (cutoff: median) at C4. In conclusion, ctDNA monitoring for sensitizing EGFR mutations at C4 is suitable for predicting the treatment outcomes in NSCLC patients receiving osimertinib (Clinical Trial Registration No.: UMIN000022076).

Abbreviations

CIs
confidence intervals
ctDNA
circulating tumor DNA
ddPCR
droplet digital PCR
EGFR
epidermal growth factor receptor
MFs
mutant fractions
NGS
next‐generation sequencing
NSCLC
non‐small cell lung cancer
ORR
overall response rate
OS
overall survival
PD
progressive disease
PFS
progression‐free survival
PR
partial response
SD
stable disease
TKI
tyrosine kinase inhibitor
  相似文献   
3.
BackgroundLocomotive syndrome is a condition of reduced mobility due to problems with locomotive organs. Although lumbar spinal canal stenosis is one of the major diseases constituting locomotive syndrome, only few studies have focused on the association between the two pathologies. We aimed to investigate the effect of surgery on lumbar spinal canal stenosis with respect to locomotive syndrome using various physical function tests, including locomotive syndrome risk tests, before and after surgery.MethodsClinical data of 101 consecutive patients (male = 46; female = 55; mean age, 69.3 years) who underwent surgery for lumbar spinal canal stenosis at our institute were prospectively collected. Results of physical function tests, including stand-up test, two-step test, and 25-Question Geriatric Locomotive Function Scale, and the sagittal vertical axis were evaluated before and 1 year after surgery. The association between several parameters and improvement of risk level in locomotive syndrome was evaluated.ResultsIn the total assessment, 93.1% of cases were in stage 2 and 6.9% in stage 1 preoperatively, while 72.4% were in stage 2, 22.4% in stage 1, and 5.2% in stage 0 at 1 year postoperatively. Postoperative improvement in the total assessment was observed in 28.7% of cases. Several physical function tests and sagittal vertical axis showed significant improvement after surgery. On multiple logistic regression analysis, age >75 years (odds ratio = 10.9, confidence interval = 1.09–109) and postoperative sagittal vertical axis >40 mm (odds ratio = 17.8, confidence interval = 1.78–177) were significant risk factors associated with non-improvement in risk level of locomotive syndrome.ConclusionsSurgical treatment for lumbar spinal canal stenosis improved physical function, including locomotive syndrome. Risk factors associated with non-improvement of locomotive syndrome were later-stage elderly and postoperative sagittal balance impairment.  相似文献   
4.
5.

Introduction

Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined.

Methods

We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT.

Results

We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 μGy, whereas the maximum dose around the eye was approximately 10 μGy.

Conclusion

By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation.  相似文献   
6.
Journal of Assisted Reproduction and Genetics - To determine age-adjusted overall success rates for patients undergoing clomiphene citrate only minimal stimulation cycle (mini) in vitro...  相似文献   
7.
To obtain baseline data for cervical cancer prevention in Japan, we analyzed human papillomavirus (HPV) data from 5045 Japanese women aged less than 40 years and diagnosed with cervical abnormalities at 21 hospitals during 2012‐2017. These included cervical intraepithelial neoplasia grade 1 (CIN1, n = 573), CIN2‐3 (n = 3219), adenocarcinoma in situ (AIS, n = 123), and invasive cervical cancer (ICC, n = 1130). The Roche Linear Array was used for HPV genotyping. The HPV type‐specific relative contributions (RCs) were estimated by adding multiple infections to single types in accordance with proportional weighting attributions. Based on the comparison of type‐specific RCs between CIN1 and CIN2‐3/AIS/ICC (CIN2+), RC ratios were calculated to estimate type‐specific risks for progression to CIN2+. Human papillomavirus DNA was detected in 85.5% of CIN1, 95.7% of CIN2‐3/AIS, and 91.2% of ICC. Multiple infections decreased with disease severity: 42.9% in CIN1, 40.4% in CIN2‐3/AIS, and 23.7% in ICC (P < .0001). The relative risk for progression to CIN2+ was highest for HPV16 (RC ratio 3.78, 95% confidence interval [CI] 3.01‐4.98), followed by HPV31 (2.51, 1.54‐5.24), HPV18 (2.43, 1.59‐4.32), HPV35 (1.56, 0.43‐8.36), HPV33 (1.01, 0.49‐3.31), HPV52 (0.99, 0.76‐1.33), and HPV58 (0.97, 0.75‐1.32). The relative risk of disease progression was 1.87 (95% CI, 1.71‐2.05) for HPV16/18/31/33/35/45/52/58, but only 0.17 (95% CI, 0.14‐0.22) for HPV39/51/56/59/66/68. Human papillomavirus 16/18/31/33/45/52/58/6/11 included in a 9‐valent vaccine contributed to 89.7% (95% CI, 88.7‐90.7) of CIN2‐3/AIS and 93.8% (95% CI, 92.4‐95.3) of ICC. In conclusion, our data support the Japanese guidelines that recommend discriminating HPV16/18/31/33/35/45/52/58 genotypes for CIN management. The 9‐valent vaccine is estimated to provide over 90% protection against ICC in young Japanese women.  相似文献   
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