Understanding the Role of the Pulmonologist in the Diagnosis and Management of Lung Cancer

Harmeet S. Bedi, MD

Pulmonologists play an important role in the diagnosis and management of patients with lung cancer, explained Harmeet S. Bedi, MD, who added that emerging technologies have the potential to improve the efficiency with which each is employed.

Lung Cancer Diagnostics

The number of lung nodules that are biopsied by interventional radiology is approximately 70% to 80% in the United States, said Bedi. The remaining 20% to 30% of nodules are biopsied by pulmonologists and bronchoscopists, having jumped 10% to 20% over the past decade, added Bedi.

This is largely attributed to the development and availability of navigation bronchoscopy, which allows pulmonologists to take a CT scan and register it to a patient intraprocedurally, using that as a sort of “google maps” to get to the lung nodule, said Bedi.

“Being inside of the airways is quite challenging for pulmonologists when you’re trying to go out to a peripheral lung nodule, but this technology has really helped us out quite a bit,” said Bedi, director of Interventional Pulmonology and Bronchoscopy at Stanford University School of Medicine, and a clinical assistant professor of Medicine - Pulmonary, Allergy & Critical Care Medicine at Stanford Health Care, in a presentation during the 22nd Annual International Lung Cancer Congress^®, a program hosted by Physicians’ Education Resource^®, LLC.¹

Another technology that is often used to identify lung nodules is radial endobronchial ultrasound, which differs from endobronchial ultrasound (EBUS), said Bedi. Radial EBUS is comparable to intravascular ultrasound, where pulmonologists can put out an ultrasound probe that displays a 360-degree image, allowing them to differentiate an eccentric nodule from a concentric nodule.

“A concentric image can really enhance your diagnostic yield bronchoscopically,” said Bedi.

Robotic bronchoscopy, having only emerged 2 years ago, can be used as an alternative to flexible bronchoscopy and comes without the difficulties of maintaining a flexible scope, said Bedi.

“[With flexible bronchoscopy], there has to be an operator that is flexed. Calmly, I’ll be telling my fellow, ‘You better not move for the next 5 minutes’ because if they move, we’re going to lose our target,” said Bedi.

With robotic bronchoscopy, the scope is completely motorized and accompanied by a controller that allows navigation to the target, which, once reached, will no longer move.

The first robotic bronchoscopy machine, Monarch, released by Auris Health, uses a controller “very similar to an Xbox where you stand at a monitor on the side of the patient and you navigate with your controller,” said Bedi.

Ion, developed by Intuitive, is another robotic-assisted bronchoscopy tool in which a scroll wheel is used to move the robot in and out and a track ball is used for aim.

“This tool has navigation software built in, which allows us to navigate out, and once you get to your target, it’ll stay fixed, so you can stand on the side of the patient or even outside the room without it moving at all,” said Bedi.

Notably, this software is likely to extend into the world of therapeutics in the future, added Bedi.

Cone-beam CT-guided bronchoscopy is another emerging tool that is used to identify lung nodules but is likely to distinguish itself by becoming “the future of pulmonology in [its ability to deliver] gold-standard confirmation,” said Bedi.

The approach has the added advantage of having a lower rate of pneumothorax and being able to reach areas where interventional radiology–guided biopsy can’t, said Bedi.

In terms of staging, EBUS has become a common part of lung cancer management, said Bedi. The tool resembles a generic flexible scope but has an ultrasound probe at the tip that allows visibility into the airway walls, said Bedi. The needle can be ejected 4 cm and can also be agitated under live ultrasound guidance, “which is why we’ve been able to really improve the diagnostic sensitivity of staging,” said Bedi.

Additionally, several systemic reviews and meta-analyses have shown a pooled sensitivity for EBUS lung cancer staging between 88% and 93%, with deemed equivalence to mediastinoscopy, said Bedi.

“[EBUS] has made its way through all the chest guidelines for managing and staging non–small cell lung cancer where it has a pretty high recommendation over surgical staging for patients that have an enlarged lymph node on CT imaging or a PET positive–node,” said Bedi.

However, Bedi cautioned that if EBUS is negative and there is clinical suspicion of tumor, additional steps should be taken to confirm the presence or lack thereof.

Lung Cancer Therapeutics

Pulmonologists also play a substantial role in the management of airway obstruction with malignant or benign origin. Specifically, pulmonologists treat endoluminal growth from the tumor, which leads to extrinsic compression of airways or airway abnormalities tied to post–radiation stenoses or general post–treatment shrinkage, said Bedi.

“Either way, flexible and/or rigid bronchoscopy can be done, most commonly by interventional pulmonologists as well as thoracic surgeons,” said Bedi.

For tumor debulking, Bedi cited laser bronchoscopy, argon plasma coagulation, and electrocautery as primary interventions.

“We can usually debulk these tumors quite safely under rigid bronchoscopy, and then depending on each patient’s situation, we can consider the placement of a stent,” said Bedi.

For patients that have extrinsic compression, a stent is strongly recommended and is often placed concurrently with treatment, whether that be radiation and/or chemotherapy, said Bedi.

However, it generally otherwise avoided given the potential for stent-related complications, Bedi added.

In terms of malignant pleural effusion, which most patients will encounter throughout their disease course, PleurX catheters can be of particular benefit, especially for those who are symptomatic.

“If the patient is symptomatic, we have to do a thoracentesis,” said Bedi.

In conclusion, Bedi called attention to bronchoscopic local therapy delivery, stating, “this is where the future of pulmonology is going to be in terms of assisting lung cancer care.”

Reference

1. Bedi HS. Role of the pulmonologist in diagnosis & management of lung cancer. Presented at: 22nd Annual International Lung Cancer Congress^®, a program hosted by Physicians’ Education Resource^®, LLC; July 29-31, 2021; hybrid interactive conference.