According to the latest findings of a prospective study, patients with early-stage non-small cell (NSC) lung cancer showed similar effects of long-term survival for both surgery and stereotactic ablative radiotherapy (SABR). The study was published in The Lancet Oncology. During an additional analysis, researchers also examined 80 patients with NSC lung cancer at medically operable stage IA. and treated with SABR. They found an overall survival (OS) rate of 91% at three years and 87% at five years.
A similar cohort study confirmed the OS rate in NSC lung cancer
In contrast, researchers found a 91% OS rate at three years and 84% at five years in another similar cohort study for early-stage NSC lung cancer patients. The study involved mediastinal lymph node dissection (MLND) using video-assisted thoracoscopic surgery (VATS).
The 3-year growth-free survival (GFS) rate was also similar between the two groups of patients. It was around 80% for patients undergoing SABR and 88% for patients undergoing surgery. However, in 5 years, these rates decreased to 77% and 80%, respectively.
SABR and surgery both have the same long-term survival
In their paper, Chang and their team wrote that the long-term results of similar trials further extended the outcomes of published prospective studies. It confirmed that both SABR and surgery achieve the same long-term survival for patients with early-stage NSC lung cancer that was operable. In addition, the long-term results of the non-randomize revised STARS trial showed that in terms of growth-free survival and total survival, SABR was not substandard to MLND with VATS for patients with stage IA NSC lung cancer.
Which one is the best option: SABR and surgery?
Alexander Louie, MD, is a co-author of the study. He is also a senior researcher at the University of Toronto and the Sunnybrook Health Sciences Center. In contrast, writing in an accompanying commentary, Louieasked whether it was the right time to announce a preliminary draw between SABR and surgery. And he also asked which one would be the best treatment for lung cancer in light of these new findings. Lung cancer commentators further added that we designed the currently ongoing randomized controlled trials to define the winners.
Several other trials are currently undergoing to confirm the results
Among all these trials, STABLE-MATES is one of the critical trials. Researchers will compare OS rates between operable NSC lung cancer patients with high-risk factors pre-treated with SABR and patients who underwent subtotal resection. Additionally, in another trial, VALOR, they will compare the OS rate for patients treated with lobectomy to those treated with SABR.
The commentators explained that it is pretty challenging to complete randomized control trials that compare surgery with non-surgical cancer treatments. The reason is that patients and healthcare providers have challenges in both equipment and priority. The STARS trial has further strengthened the validation of the equipment required for these Phase III trials.
How many treatment options are available for lung cancer currently?
Louie and the team concluded that there would be only two outstanding treatment options for long-term survival until we complete these randomized controlled trials. And these treatments are specially for those younger and fitter patients who present with stage IA NSC lung cancer.
Previous pooled analysis conducted by Chang and colleagues for patients admitted to ROSEL and STARS trials revealed that SABR significantly increased the rate of OS than MLND. However, Chang and colleagues also pointed out several significant limitations to this analysis.
SABR treatment caused shrinkage of the tumor
To compensate, investigators reassembled the SABR group within the STARS trial with larger sample size. Afterward, they compared the similarities with a contemporary group of patients undergoing MLND with VATS. And these patients were admitted to MD Anderson Cancer Center at the University of Texas. However, the present analysis did not involve NSC lung cancer patients from the original STARS trial.
Furthermore, they identified NSC lung cancer in patients with pretreated SABR. The tumor diameter of most of the patients in this group was 3 cm or less. At the same time, the average tumor size for this group was only 1.83 cm. And around two-thirds of the tumors of those NSC lung cancer patients were adenocarcinomas.
SABR did not show any side effects during the study
Researchers gave SABR treatment at 54 Gy dose in three portions to treat peripheral lesions. At the same time, they gave a 50 Gy dose in four portions to treat central tumors. However, at the same time, they simultaneously increased the amount to a gross tumor totaling 60 Gy. The team said that every patient accomplished the SABR trial within four days. In addition, they all underwent this radiotherapy for one week without any side effects.
OS rate of surgery and SABR groups did not have significant differences
Moreover, researchers added all 352 patients who underwent MLND through VATS during the enrollment period in the surgical database of Phase I NSC lung cancer participants. It helped match the Propensity Score with the SABR group. The primary endpoint was to identify the overall survival in three years. The researchers reported that based on multivariable analysis, they did not find a significant difference in OS rate between these two groups (HR 0.86, 95 ٪ CI 0.45-1.65).
Researchers further found that the cancer-specific survival rates became comparable at three years between these two groups. It was 97% for the surgery patients and 95% for the SABR group. On the other hand, cancer-specific survival rates at five years were 93% and 92%, respectively.
SABR patients had higher local and regional recurrence rates
As far as local recurrence rates are concerned, it was 1.3% for the MLND through VATS group at five years. And it was 6.3% for the SABR patients. Similarly, the rates of distant metastases at five years were 4.0% for the surgery group and 8.8% for SABR-treated patients.
Moreover, SABR patients also had an increased risk of regional recurrence, at 2.7 % versus 12.5%, respectively. And they all were the MLND through VATS patients (P = 0.017). However, the authors mentioned, SABR patients did not have an inferior OS rate regardless of developing regional recurrence. Mainly, they did not find any grade 4/5 toxicities among SABR patients. In comparison, there was a little bit of grade 3 toxicity rate that was only 1%.
Ever best finding on the SABR treated NSC lung cancer patients
Compared to MLND through VATS, these results are associated with a nearly 19 to 50% postoperative disease rate. The researchers wrote the results of the SABR patient in this study are among the best previously reported results.
However, they warned that since the regional recurrence risk was higher in SABR patients, thus we strongly encourage people for a close follow-up after SABR treatment. Additionally, they also recommended using preventive therapy for isolated regional and local recurrence after SABR.
The authors also warned against excluding patients with tumors larger than 3 cm and patients with “ultra-central” tumors. So it is because researchers eliminated both these groups from the study.
What is non-small cell lung cancer?
1. Non-small cell lung cancer is a chronic malignant tumor cell originating in the lung tissues.
2. Non-small cell lung cancer has several distinguished types.
3. Smoking is the leading risk factor for causing this cancer.
4. Signs and symptoms of this type of lung cancer include a long-term cough that cannot be cured and shortness of breath.
5. Currently, there are several diagnosing tests available for examining the lungs and staging cancer.
6. If a person suspects lung cancer, a doctor often recommends him for a biopsy of the lungs.
7. Currently, there are several treatment options available for NSC lung cancers, such as surgery, radiography, chemotherapy, etc.
8. Certain factors affect treatment and the chance of recovery of a patient with lung cancer.
9. However, most of the treatments cannot cure NSC lung cancer currently.
A new study suggested that early-stage NSC lung cancer patients have similar effects of long-term survival for surgery and SABR. Researchers analyzed 80 patients with medically operable NSC lung cancer at the IA stage previously treated with SABR. During the analysis, the overall OS rate was 91% at three years and 87% at five years. Researchers confirmed these percentages through a similar cohort study for the OS rate in NSC lung cancer. In that study, SABR and surgery both have a similar long-term survival rate.
To answer whether SABR and surgery is the best treatment option, researchers designed several other currently undergoing trials. But until they do not complete these trials, there are presently only two treatment options for early-stage lung cancer.
However, the study highlights the efficacy of SABR treatment, as it caused shrinkage of the tumor. Additionally, SABR also did not show any side effects in the patients during the follow-up period. Despite all these facts, there is a minor difference in the OS rate between the surgery and SABR groups.
Researchers also highlighted some limitations that SABR patients had higher local and regional recurrence rates, so they needed additional follow-up care. However, in conclusion, it was the best finding on the SABR treated NSC lung cancer patients.