You are leaving Medscape Education
Cancel Continue
Log in to save activities Your saved activities will show here so that you can easily access them whenever you're ready. Log in here CME & Education Log in to keep track of your credits.



ASTRO Issues New Guidelines on Stereotactic Radiation in Early NSCLC

  • Authors: News Author: Pam Harrison; CME Author: Charles P. Vega, MD
  • CME / CE Released: 8/3/2017
  • Valid for credit through: 8/3/2018
Start Activity

Target Audience and Goal Statement

This article is intended for primary care clinicians, radiation oncologists, surgeons, oncologists, nurses, and other clinicians who treat and manage patients with lung cancer.

The goal of this activity is to provide medical news to primary care clinicians and other healthcare professionals in order to enhance patient care.

Upon completion of this activity, participants will be able to:

  1. Assess the current practice of stereotactic body radiation therapy in cases of non-small cell lung cancer
  2. Evaluate recommendations for the application of stereotactic body radiation therapy to cases of non-small cell lung cancer


As an organization accredited by the ACCME, Medscape, LLC, requires everyone who is in a position to control the content of an education activity to disclose all relevant financial relationships with any commercial interest. The ACCME defines "relevant financial relationships" as financial relationships in any amount, occurring within the past 12 months, including financial relationships of a spouse or life partner, that could create a conflict of interest.

Medscape, LLC, encourages Authors to identify investigational products or off-label uses of products regulated by the US Food and Drug Administration, at first mention and where appropriate in the content.

News Author

  • Pam Harrison

    Freelance writer, Medscape


    Disclosure: Pam Harrison has disclosed no relevant financial relationships.


  • Robert Morris, PharmD

    Associate CME Clinical Director, Medscape, LLC


    Disclosure: Robert Morris, PharmD, has disclosed no relevant financial relationships.

CME Author

  • Charles P. Vega, MD

    Health Sciences Clinical Professor, UC Irvine Department of Family Medicine; Associate Dean for Diversity and Inclusion, UC Irvine School of Medicine, Irvine, California


    Disclosure: Charles P. Vega, MD, has disclosed the following relevant financial relationships:
    Served as an advisor or consultant for: McNeil Consumer Healthcare
    Served as a speaker or a member of a speakers bureau for: Shire Pharmaceuticals

CME Reviewer/Nurse Planner

  • Amy Bernard, MS, BSN, RN-BC

    Lead Nurse Planner, Medscape, LLC


    Disclosure: Amy Bernard, MS, BSN, RN-BC, has disclosed no relevant financial relationships.

Accreditation Statements

In support of improving patient care, Medscape, LLC is jointly accredited by the Accreditation Council for Continuing Medical Education (ACCME), the Accreditation Council for Pharmacy Education (ACPE), and the American Nurses Credentialing Center (ANCC), to provide continuing education for the healthcare team.

    For Physicians

  • Medscape, LLC designates this enduring material for a maximum of 0.25 AMA PRA Category 1 Credit(s)™ . Physicians should claim only the credit commensurate with the extent of their participation in the activity.

    This Enduring Material activity, Medscape Education Clinical Briefs, has been reviewed and is acceptable for credit by the American Academy of Family Physicians. Term of approval begins 9/1/2016. Term of approval is for one year from this date. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Approved for 0.25 AAFP Prescribed credits.

    Medscape, LLC staff have disclosed that they have no relevant financial relationships.

    AAFP Accreditation Questions

    Contact This Provider

    For Nurses

  • Awarded 0.25 contact hour(s) of continuing nursing education for RNs and APNs; none of these credits is in the area of pharmacology.

    Contact This Provider

For questions regarding the content of this activity, contact the accredited provider for this CME/CE activity noted above. For technical assistance, contact [email protected]

Instructions for Participation and Credit

There are no fees for participating in or receiving credit for this online educational activity. For information on applicability and acceptance of continuing education credit for this activity, please consult your professional licensing board.

This activity is designed to be completed within the time designated on the title page; physicians should claim only those credits that reflect the time actually spent in the activity. To successfully earn credit, participants must complete the activity online during the valid credit period that is noted on the title page. To receive AMA PRA Category 1 Credit™, you must receive a minimum score of 75% on the post-test.

Follow these steps to earn CME/CE credit*:

  1. Read the target audience, learning objectives, and author disclosures.
  2. Study the educational content online or printed out.
  3. Online, choose the best answer to each test question. To receive a certificate, you must receive a passing score as designated at the top of the test. We encourage you to complete the Activity Evaluation to provide feedback for future programming.

You may now view or print the certificate from your CME/CE Tracker. You may print the certificate but you cannot alter it. Credits will be tallied in your CME/CE Tracker and archived for 6 years; at any point within this time period you can print out the tally as well as the certificates from the CME/CE Tracker.

*The credit that you receive is based on your user profile.


ASTRO Issues New Guidelines on Stereotactic Radiation in Early NSCLC

Authors: News Author: Pam Harrison; CME Author: Charles P. Vega, MDFaculty and Disclosures

CME / CE Released: 8/3/2017

Valid for credit through: 8/3/2018


Clinical Context

Non-small cell lung cancer (NSCLC) accounts for a higher number of fatal cancers compared with any other tumor, and the authors of the current study indicate that approximately 16% of patients with NSCLC present with early-stage disease, as defined by a tumor stage of T1-T2 N0. These patients are usually considered for primary surgical treatment, but a minority of patients with early-stage NSCLC will not be good surgical candidates.

Stereotactic body radiation therapy (SBRT) may be a good option for these patients. The current guideline defines SBRT as using very high doses of radiation in 1 to 5 fractions. SBRT also employs highly conformal techniques. It is clear that SBRT can be effective for patients with early-stage NSCLC, although the rate of treatment toxicity for tumors within 2 cm of the proximal tracheobronchial tree is higher than that encountered for peripheral tumors.

The current guidelines highlight the best practice of SBRT for early-stage NSCLC.

Study Synopsis and Perspective

The American Society for Radiation Oncology (ASTRO) has issued new guidelines on the appropriate use of SBRT in early-stage NSCLC, now the leading cause of cancer-related death for both men and women in the United States.

"Early-stage NSCLC in medically fit patients is traditionally managed surgically," the guideline authors write. "[H]owever, many patients are medically inoperable because of comorbidities."

Because conventional radiation is associated with both toxicity and local failure in medically inoperable patients, SBRT has emerged as the standard of care for these early-stage patients.

The guideline is published online in Practical Radiation Oncology.

"With longer life expectancies and more sophisticated diagnostic tools, we have seen a rise in the incidence of early-stage lung cancer, including among patients who are not able to undergo surgery or choose not to do so," commented cochair of the ASTRO Task Force, Gregory Videtic, MD, from the Cleveland Clinic in Ohio.

"SBRT provides an option for these patients...and increasing access to this potentially life-saving treatment is essential to improve outcomes for the growing population of early-stage NSCLC patients," Dr Videtic said in a statement.

Nevertheless, controversy over the use of SBRT remains for patients with large, multifocal, recurrent, or centrally located tumors, as well as for patients who lack tissue confirmation and those with recurrent disease.

To address these challenging clinical scenarios, guideline authors reviewed the literature and produced a consensus document to guide physicians involved in the management of early-stage NSCLC in their decision-making.

The guideline emphasizes that SBRT is not recommended as an alternative to surgery for patients with stage I NSCLC who are at standard operative risk. For this patient group, lobectomy with systematic mediastinal lymph node evaluation is the recommended procedure of choice.

The guideline adds that SBRT should be discussed as a potential alternative to sublobar resection in patients with stage I NSCLC at high operative risk.

Medically Inoperable Patients

For medically inoperable patients, ASTRO's new recommendations vary according to tumor location, size, and type, as well as treatment history. The guidelines state that:

  • SBRT is appropriate for centrally located tumors, but toxicity risks depend on both the total dose of radiation used and the fractionation schedule. When used, SBRT directed at central tumors should be delivered in 4 or 5 fractions; however, for central tumors deemed to be too high risk for SBRT, hypofractionated radiation therapy, given in 6 to 15 fractions, may be considered.
  • SBRT is also considered to be appropriate for tumors in excess of 5 cm in diameter. As is true for the treatment of central lung tumors, adherence to volumetric and maximum dose restrictions may help improve the safety profile of SBRT in both groups of patients.
  • In patients who do not have tissue confirmation of a malignant lung nodule (wherever possible, physicians should try to obtain a biopsy specimen before SBRT), SBRT can be used, but only after a multidisciplinary discussion of this option to ensure the characteristics of the lesion in question are consistent with a malignant lung nodule.
  • Multiple primary lung cancers (MPLCs) are often difficult to distinguish from intrathoracic metastatic lung cancer, and they need to be evaluated by a multidisciplinary team. Positron emission tomography, computed tomography, or magnetic resonance imaging of the brain should be used to help differentiate patients with MPLC from those with intrathoracic metastatic lung cancer. "SBRT may be considered as curative for patients with synchronous MPLC," guideline authors note.
  • Similarly, SBRT may be considered as curative for patients with metachronous MPLCs, even in patients who have previously undergone pneumonectomy and who now have a new primary cancer in their remaining lung.

Again in medically inoperable patients, the new guidelines describe how SBRT may be tailored for use in high-risk scenarios, when, for example, the tumor abuts critical structures, such as the bronchial tree, esophagus, heart, or chest wall.

  • When close to the proximal bronchial tree, heart, and pericardium, "SBRT should be delivered in 4 to 5 fractions," the guideline authors advise, because serious toxicities to these organs are typically limited.
  • In contrast, physicians need to adhere to the constraints reported in the literature if the tumor is close to the esophagus because severe toxicities can be inflicted on the esophagus on treatment of tumors in close proximity to it.
  • SBRT also should be offered to patients with T1-T2 tumors that abut the chest wall. The authors note that even though toxicity to the chest wall after SBRT treatment is common, it usually resolves with minimal treatment.
  • SBRT may be used in patients with cT3 disease resulting from chest wall invasion, they add.

The guideline authors also describe a role for SBRT for medically inoperable patients with recurrent early-stage disease. Recommendations again vary according to treatment history.

  • Salvage SBRT may be used after patients have received primary conventionally fractionated radiation, but patient selection for salvage SBRT should be highly individualized. Patients also should be aware of significant, even fatal, toxicities associated with salvage SBRT after conventional radiation.
  • Selecting patients for salvage SBRT after they have undergone a sublobar resection should also be highly individualized.

Dr Videtic has disclosed no relevant financial relationships.

Pract Radiat Oncol. Published online June 12, 2017.[1]

Study Highlights

  • The recommendations were developed by a task force assembled by ASTRO. It included radiation oncologists, surgeons, and a patient representative.
  • The task force reviewed studies regarding SBRT for early-stage lung cancer. All included research was published between 1995 and 2015. A total of 172 studies were included in the final recommendation analysis.
  • Patients with operable stage I NSCLC should be evaluated by a thoracic surgeon to reduce the risk for specialty bias. For patients with an anticipated risk for mortality in surgery of less than 1.5%, SBRT is not recommended as a routine option instead of surgery.
  • Long-term outcomes of SBRT for low-risk NSCLC beyond 3 years are largely unknown, and this should be discussed with patients during medical decision-making.
  • SBRT directed at central lung tumors should be delivered in 4 or 5 fractions. Hypofractionation with 6 to 15 fractions may be considered for very high-risk central tumors.
  • Patients should have a biopsy before SBRT, if possible, to establish the presence of malignancy. However, SBRT can be delivered to patients who refuse biopsy or who have a nondiagnostic biopsy.
  • SBRT for multiple primary lung cancer is associated with similar local control as for SBRT for single lung tumors, but overall survival for patients with multiple sites of lung cancer is worse despite treatment with SBRT.
  • SBRT can be considered a curative treatment option among patients with multiple primary lung cancer after pneumonectomy. Toxicity of SBRT may be increased among these patients.
  • SBRT should be delivered in 4 or 5 fractions for tumors in close proximity to the proximal bronchial tree. Esophageal toxicity is significant for patients with tumors in close proximity to the esophagus.
  • SBRT is less likely to be toxic to the heart and associated structures, and tumors in close proximity to the heart may be treated with 4 or 5 fractions.
  • Grade 1 and 2 chest wall toxicity is common after SBRT. It usually resolves with conservative management.
  • SBRT may be used among patients with cT3 disease resulting from chest wall invasion. In addition, SBRT may be offered as salvage therapy after primary conventional fractionated radiation to selected patients. SBRT has been associated with good results for local control and survival among these patients. However, patients considered for salvage SBRT should be counseled about potentially severe toxicity associated with treatment.

Clinical Implications

  • SBRT uses very high doses of radiation in 1 to 5 fractions. SBRT also employs highly conformal techniques. The rate of treatment toxicity associated with SBRT for tumors within 2 cm of the proximal tracheobronchial tree is higher than that encountered for peripheral tumors.
  • The current guidelines suggest SBRT should be a secondary option after surgery among patients with operable stage I NSCLC. The outcomes of SBRT beyond 3 years among these patients are uncertain. Patients should have a biopsy before SBRT, and tumors in close proximity to the heart may be treated with 4 or 5 fractions.
  • Implications for the Healthcare Team: The current guidelines recommend a process of shared decision-making with an objective balance between different treatment options for patients with early-stage NSCLC.

CME Test