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The advent of precision medicine has changed the landscape of oncologic biomarkers, drug discovery, drug development, and, more importantly, outcomes for patients with cancer. Precision oncology entails the genomic profiling of tumors to detect actionable aberrations. The advances in clinical next-generation sequencing from both tumor tissue and liquid biopsy and availability of targeted therapies has rapidly entered mainstream clinical practice. In this review, recent major developments in precision oncology that have affected outcomes for patients with cancer are discussed. Rapid clinical development was seen of targeted agents across various mutational profiles such as KRASG12C (which was considered “undruggable” for almost 4 decades), Exon 20 insertions, and RET mutations. Approaches to precision chemotherapy delivery by the introduction of antibody drug conjugates in the armamentarium against lung cancer has been appreciated.  相似文献   
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Methadone has several unique characteristics that make it an attractive option for pain relief in serious illness, but the safety of methadone has been called into question after reports of a disproportionate increase in opioid-induced deaths in recent years. The American Pain Society, College on Problems of Drug Dependence, and the Heart Rhythm Society collaborated to issue guidelines on best practices to maximize methadone safety and efficacy, but guidelines for the end-of-life scenario have not yet been developed. A panel of 15 interprofessional hospice and palliative care experts from the U.S. and Canada convened in February 2015 to evaluate the American Pain Society methadone recommendations for applicability in the hospice and palliative care setting. The goal was to develop guidelines for safe and effective management of methadone therapy in hospice and palliative care. This article represents the consensus opinion of the hospice and palliative care experts for methadone use at end of life, including guidance on appropriate candidates for methadone, detail in dosing, titration, and monitoring of patients' response to methadone therapy.  相似文献   
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Background

Recently developed convolutional neural network (CNN) models determine bone age more accurately than radiologists.

Objective

The purpose of this study was to determine whether a CNN and radiologists can accurately predict bone age from radiographs using only the index finger rather than the whole hand.

Materials and methods

We used a public anonymized dataset provided by the Radiological Society of North America (RSNA) pediatric bone age challenge. The dataset contains 12,611 hand radiographs for training and 200 radiographs for testing. The index finger was cropped from these images to create a second dataset. Separate CNN models were trained using the whole-hand radiographs and the cropped second-digit dataset using the consensus ground truth provided by the RSNA bone age challenge. Bone age determination using both models was compared with ground truth as provided by the RSNA dataset. Separately, three pediatric radiologists determined bone age from the whole-hand and index-finger radiographs, and the consensus was compared to the ground truth and CNN-model-determined bone ages.

Results

The mean absolute difference between the ground truth and CNN bone age for whole-hand and index-finger was similar (4.7 months vs. 5.1 months, P=0.14), and both values were significantly smaller than that for radiologist bone age determination from the single-finger radiographs (8.0 months, P<0.0001).

Conclusion

CNN-model-determined bone ages from index-finger radiographs are similar to whole-hand bone age interpreted by radiologists in the dataset, as well as a model trained on the whole-hand radiograph. In addition, the index-finger model performed better than the ground truth compared to subspecialty trained pediatric radiologists also using only the index finger to determine bone age. The radiologist interpreting bone age can use the second digit as a reliable starting point in their search pattern.

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BACKGROUNDColorectal cancer (CRC) is the third leading cause of cancer-related death in males and females in the United States. Approximately, 20%-22% of patients have metastatic disease at the time of presentation, and 50%-60% will develop metastasis over the course of their disease. Despite advances in systemic therapies, there remains a paucity of effective third- and later-line therapies for patients with ongoing disease progression. However, rechallenging chemo-resistant CRC tumors with previously administered therapies is an emerging concept that may be a life-prolonging option for heavily treated metastatic colorectal cancer (mCRC).CASE SUMMARYA 41-year-old man with no previous medical history initially presented with worsening diffuse abdominal tenderness. Computed tomography was significant for a splenic flexure mass and hepatic lesions concerning for metastatic disease. He underwent a colectomy with anastomosis. Postoperative pathology was diagnostic for moderately to well-differentiated adenocarcinoma (T4bN1bM1a). He received adjuvant 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX), but therapy was discontinued due to the development of atrial fibrillation. Additional workup indicated a carcinoembryonic antigen level of 508.2 ng/mL, and mutational analysis found that the tumor was microsatellite instability-high and KRAS/BRAF wild-type. He was started on irinotecan with oxaliplatin (IROX), and bevacizumab (14 cycles), developed disease progression, was transitioned to FOLFOX and cetuximab, and then eventually three cycles of pembrolizumab. Following disease progression, he was rechallenged with IROX therapy, as he previously responded well to oxaliplatin-based therapy. The IROX rechallenge provided this patient with a ten-month survival benefit, decreased metastatic burden, and marked improvement in his clinical condition.CONCLUSIONRechallenge of previous lines of well-tolerated systemic chemotherapy regimens may be a valuable therapeutic strategy in patients with heavily-treated mCRC.  相似文献   
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