There are early and late stages of lung cancer.
Among the various stages, the IA stage is the earliest and the most effective for treatment.
Postoperative adjuvant chemotherapy in this group is completely unnecessary according to extant guidelines and evidence-based medical evidence.
But, is that really the case?
Research Report 1
A study examining the relationship between airspace dissemination and adjuvant chemotherapy efficacy was published in December 2020.
The study screened lung cancer patients treated between 2009 and 2013 and included medical data from five medical centers in the country.
Patients with stage I lung adenocarcinoma who elect to undergo surgery.
Ultimately, 3,346 patients were enrolled, of whom 1,082 (32.3%) were accompanied by airspace dissemination (STAS).
In the whole group, 1514 (45.2%) patients underwent lobectomy and 1832 (54.8%) patients underwent sublobar resection, of which 15.2% were treated with postoperative adjuvant chemotherapy (n=509).
Analysis revealed that adnexal growth was the predominant type of lung adenocarcinoma, with no airspace dissemination in super eight layers (81.8%).
Airspace dissemination shows a strong prognostic impact of.
#1 Airspace dispersal affects long term survival
Survival analysis showed that patients with combined airspace dissemination had more rapid recurrence and shorter survival.
#2 Effectiveness of surgical treatment for airborne disruption
In terms of surgery, stage IA lung adenocarcinoma with combined airspace dissemination has worse outcomes in those who undergo sublobar resection.
#3 Airspace dissemination affects adjuvant chemotherapy in stage IB lung adenocarcinoma
For patients with stage IB, the authors performed a subgroup analysis.
The results showed that those who received lobectomy with postoperative adjuvant chemotherapy had significantly better long-term treatment outcomes than the other subgroups.
#4 Airspace dissemination affects the outcome of surgical treatment of stage IA lung adenocarcinoma
For stage IA lung cancer, airspace dissemination affects the outcome of surgical treatment.
In a population without airspace dissemination, lobectomy and sublobar resection had no significant effect on long-term outcome.
In the combined airspace dissemination population, lobectomy treatment was more effective.
Compared to sublobar resection, the risk of death and recurrence were significantly reduced by 50% in the lobectomy group.
Risk of death, aHR=0.509; risk of recurrence, aHR=0.470.
#5 Adjuvant chemotherapy necessity in stage IA patients with combined airspace dissemination
Since airspace dissemination affects the outcome of surgical treatment, should we add adjuvant chemotherapy?
In response to this question, the authors conducted further group analysis.
Adjuvant chemotherapy improves outcomes in people with combined airspace dissemination who undergo sublobar resection.
In those with combined airspace dissemination who underwent lobectomy, adjuvant chemotherapy did not significantly improve long-term outcomes.
Research Report 2
A study examining the relationship between the percentage of micropapillary component and the efficacy of adjuvant chemotherapy in stage IA lung adenocarcinoma was published in June 2020.
The authors screened 152 pathologically confirmed micropapillary component-dominant stage IA lung adenocarcinomas from the Department of Thoracic Surgery, Qilu Hospital.
All patients underwent lobectomy.
Of these, 73 received postoperative adjuvant chemotherapy, while 79 did not receive postoperative adjuvant chemotherapy.
Comparison found that receiving postoperative adjuvant chemotherapy resulted in better overall survival time and delayed recurrence.
The prognostic impact of postoperative chemotherapy remained significant even after correcting for the effects of other prognostic factors.
Receiving post-operative chemotherapy can reduce the risk of recurrence by 55% and can reduce the risk of death by 51%.
PFS, corrected HR=0.454; OS, corrected HR=0.489
Is adjuvant chemotherapy absolutely unnecessary after surgery for stage IA lung cancer?
For many years, we have been accepting the idea that stage IA lung cancer, with its excellent prognosis, does not require postoperative adjuvant chemotherapy.
However, there is a problem here.
Stage IA lung cancer is patients with less than 3cm and no lymph node metastasis.
Thanks to the JCOG series of clinical studies, this group, is now increasingly undergoing sublobar resection.
JCOG0802 study: the era of sublobar resection 3.0 has arrived.
However, in fact, the evidence-based medical evidence for postoperative adjuvant chemotherapy in stage IA is overwhelmingly built on the basis of lobectomy.
So is such a recommendation still appropriate for stage IA lung cancer under sublobar resection?
In addition, with the new pathological subtypes of lung adenocarcinoma, our understanding of stage IA lung cancer is becoming more sophisticated.
So, do all stage IA lung adenocarcinomas have a good prognosis?
In this, there is definitely a bias.
Thus, in the previous section, we identified two key high-risk factors.
One of them, air cavity dispersal.
Second, the micropapillary component dominates the type.
Airspace dispersal (STAS)
For what is airspace dissemination, Dr. Cheng has shared a post that you can read for yourself if you are interested.
Airspace dissemination (STAS), the man behind the interference with the efficacy of surgery for early stage lung cancer.
noted that airspace dissemination does significantly interfere with the prognosis of patients with early-stage lung cancer.
However, the effect of airspace dissemination differs in hairy glass lung cancer and solid lung cancer.
First, airspace dissemination is more commonly seen in lung cancers with solid nodules on imaging.
The figure below is an excerpt from a meta-analysis in which the authors analyzed the relationship between the percentage of hairy glass component on imaging and airspace dissemination; the greater the percentage of hairy glass component, the higher the likelihood of airspace dissemination.
In purely solid nodules, airspace dissemination occurs in up to 70% of patients.
The risk of STAS is significantly increased 2.95-fold when the percentage of solid component of pulmonary nodules exceeds 50%.
Second, the adverse prognostic effect of airspace dissemination seems to be significant only in solid nodules.
A retrospective study was published in the 2020 issue of
In this study, the authors retrospectively analyzed the medical history data of patients with stage I lung adenocarcinoma who underwent lobectomy at the Shanghai Pulmonary Hospital between 2011.1 and 2012.12.
Ultimately, 620 cases of the target population were included, of which 167 (26.9%) were positive for airspace dissemination (STAS).
Of these, 145 appeared in purely solid nodules, accounting for 86.8%.
Further analysis revealed that
The prognostic impact of airspace dissemination is seen only in solid nodules and loses significance in the hairy glass population.
It was also because of this phenomenon that I wrote this post at the time.
What happens when hairy glass lung adenocarcinoma meets airspace dissemination, when the fastest spear, meets the hardest shield?
Micropapillary component dominant type (MPP)
In 2010, scholar Sica had published a prognostic risk stratification for lung adenocarcinoma based on the pathological subtypes of lung adenocarcinoma.
Low risk, defined as the adnexal growth-dominant type.
Moderate risk, meaning that the glandular vesicle or papillary component is the predominant type.
High risk, which refers to the solid or micropapillary component dominant type.
It was noted that the higher the risk level, the worse the treatment outcome.
In 2021, a study was published that included 789 patients with stage I lung adenocarcinoma and validated the validity of this staging system.
Through further analysis, it was found that
The grading system proposed by Sica based on the delineation of maximum pathological subtypes is superior to other pathological grading systems.
In addition to the Sica system, there are two other grading systems, one proposed by the scholar Architectural and one proposed by IASLC.
This will not be repeated.
Among the different grading systems, and despite the controversy at the many grading junctions, there is no doubt about one thing.
It is the lung adenocarcinoma with predominantly solid/micro papillary component that are the most at risk group in the stage I group.
The long term effect is the worst.
The previous study, however, further extends the idea that it is because of the poor outcome that surgery alone is not sufficient to ensure long-term results and that postoperative adjuvant chemotherapy should be added.
Write at the end
The topic of this issue is explored because of the significant prognostic risk differences in stage IA lung cancer.
Some of them are very good.
For example, in that group with less than 50% solid component, a surgical cut is a cure and will not recur.
If wool glass is king, it is the king of kings!
However, except for this group, it can be said that all are at risk of recurrence.
In the group at risk of recurrence, if the risk is high, should chemotherapy be given or not?
With this question in mind, I found the two studies mentioned above.
Some may say, Dr. Cheng, the studies you shared this time are some real world data and the level of evidence is not very high.
But evidence that is not high, is also evidence, it is just a matter of how we interpret it.
From the study data, it appears that
Regarding the airspace dissemination one study, which included treatment data from 5 medical centers, the large sample size and the population covered, although retrospective, are sufficient to show the relevance of STAS and adjuvant chemotherapy.
For the micropapillary component-dominant study, although the overall sample size was only 152, all included patients met all 3 criteria: stage IA pathology, micropapillary component-dominant type, and underwent standard lobectomy.
On this basis, 73 in the study received postoperative adjuvant chemotherapy, while 79 did not, with similar sample sizes in the treatment and control groups.
The high degree of consistency in the data sources, and the evenness between the comparison groups, makes such an analysis credible enough in terms of answering a single question.
These studies, which give us a heads up, also suggest more dialectical thinking about the perfect results of JCOG 0802.
Even if you have stage IA lung adenocarcinoma, some of them have a poor prognosis and even rely on postoperative chemotherapy to ensure the efficacy of treatment.
In life, we often describe such a group of people.
It looks shiny, but it turns out to be rotten inside.
Combined airspace dissemination, or manifestation of a predominantly micropapillary component, may be the case.
Even for the IA period, the results were not good.
Like an embroidered pillow, just a nice skin, inside is a belly of grass.