人工智能系统大大提高了肺癌的预测

Researchers: AI System Greatly Improves Lung Cancer Predictions

Researchers have developed a new machine system that they say can detect lung cancer as well as or better than doctors.

The system is powered by a deep learning algorithm that researchers from Google and Northwestern University created. Deep learning is a method of artificial intelligence or AI that teaches computers to learn by example.

The system is explained in a study published in the journal Nature Medicine.

The World Health Organization, or WHO, reports lung cancer is the most common form of cancer across the world. The WHO estimates that each year, lung cancer results in about 1.7 million deaths. Lung cancer has one of the worst survival rates among all cancers. However, as is the case with most cancers, survival rates can be greatly improved when the disease is caught early.

For many years, doctors have attempted to improve screening methods to detect lung cancer. The most common tool currently used is computed¹ tomography, or CT. A CT scan uses X-rays and a computer to make detailed² images of bones, organs and other tissue inside the body.

Doctors who are trained to study CT images of tissue examine the scans to look for evidence of cancer. The process can involve hundreds of images.

The examination of CT scans to detect lung cancer has been shown to reduce death rates by 20 to 43 percent, the study said. But it also noted³ that the method also results in a high rate of false-positive or false-negative cancer diagnoses.

The new deep-learning system uses an algorithm and three-dimensional or 3D technology to examine the CT scans, Google reported on its website. The method works by learning how to detect signs of cancer from a large number of CT samples.

The study reports the system was tested on 6,716 cases with known diagnoses, in partnership⁴ with the National Cancer Institute. The system’s overall success rate was 94.4 percent. When examining a CT scan for diagnosis⁵, the deep-learning model performed equal to or better than six radiologists, the study found. Radiologists specialize in medical imaging to diagnose disease.

Google said in a statement, “We detected five percent more cancer cases while reducing false-positive exams by more than 11 percent compared to unassisted radiologists in our study.”

Dr. Mozziyar Etemadi is a professor of engineering at Northwestern University. He helped lead the research. He said the use of 3D technology marks a big step forward in the CT examination process.

“AI in 3D can be much more sensitive in its ability to detect early lung cancer than the human eye looking at 2D images,” Etemadi said. He added: “This is technically⁶ ‘4D' because it is not only looking at one CT scan, but two - the current and prior scan - over time.”

Lily Peng is a product manager at Google’s Brain AI Research Group. She spoke⁷ about the study’s results during Google’s I/O 2019 conference earlier this month. She noted that the deep-learning system was able to identify very small signs of lung cancer that are difficult for humans to detect.

Peng noted that the method can be especially helpful in predicting cancer in patients whose early scans do not show doctors signs of lung cancer -- even though cancer might be present. In such a case, a one-year break between CT scans could mean the cancer could become very serious before being found on a second scan.

“Our model was able to detect these early signs – one year before the patient was actually diagnosed," Peng said. “And that year could translate to an increased survival rate of 40 percent for patients like this.“

I’m Bryan Lynn.

Words in This Story

detect – v. discover or notice something

algorithm – n. set of steps that are followed in order to solve a mathematical problem or to complete a computer process

artificial intelligence – n. the ability of a machine to use and analyze⁸ data in an attempt to reproduce human behavior

screening – n. medical procedure to find out if a person has an illness by completing tests on them

diagnosis – n. a doctor’s opinion of what is wrong with someone

three-dimensional – adj. having or seeming to have length, width, depth

sensitive – adj. able to measure very small changes

prior – adj. existing or happening before something else

translate – v. to turn into or make happen

1 computed   

adj.[医]计算的，使用计算机的v.计算，估算( compute的过去式和过去分词 )

参考例句：

• He computed that the project would take seven years to complete. 他估计这项计划要花七年才能完成。 来自《简明英汉词典》
• Resolving kernels and standard errors can also be computed for each block. 还可以计算每个块体的分辨核和标准误差。 来自辞典例句

2 detailed   

adj.详细的，详尽的，极注意细节的，完全的

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。

3 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

4 partnership   

n.合作关系，伙伴关系

参考例句：

• The company has gone into partnership with Swiss Bank Corporation.这家公司已经和瑞士银行公司建立合作关系。
• Martin has taken him into general partnership in his company.马丁已让他成为公司的普通合伙人。

5 diagnosis   

n.诊断，诊断结果，调查分析，判断

参考例句：

• His symptoms gave no obvious pointer to a possible diagnosis.他的症状无法作出明确的诊断。
• The engineer made a complete diagnosis of the bridge's collapse.工程师对桥的倒塌做一次彻底的调查分析。

6 technically   

adv.专门地，技术上地

参考例句：

• Technically it is the most advanced equipment ever.从技术上说，这是最先进的设备。
• The tomato is technically a fruit,although it is eaten as a vegetable.严格地说，西红柿是一种水果，尽管它是当作蔬菜吃的。

7 spoke   

n.（车轮的）辐条；轮辐；破坏某人的计划；阻挠某人的行动 v.讲，谈（speak的过去式）；说；演说；从某种观点来说

参考例句：

• They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
• The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。

8 analyze   

vt.分析，解析 (=analyse)

参考例句：

• We should analyze the cause and effect of this event.我们应该分析这场事变的因果。
• The teacher tried to analyze the cause of our failure.老师设法分析我们失败的原因。