These two days a Shandong classmate consulted me, his father just underwent pulmonary nodular endoscopic surgery, the doctor asked the family whether to do genetic testing on the day of the operation, involving self-payment and the cost is relatively high, this classmate first thought of asking me, this genetic test must be done? I replied to him, at least wait for the surgery to come out, according to the postoperative pathology and staging before deciding, after all, more than ten thousand yuan is not a small amount. A week later the pathological results came out as carcinoma in situ. I made it clear to him that he didn't need genetic testing.
It is true that many people are confused about what genetic testing is for and whether to do it or not. Many people think that since the doctor has proposed, it is better to do than not to do it, and spend money to buy a peace of mind. The purpose of genetic testing is to determine whether the corresponding targeted drugs can be used, judge the effect of immune drugs, and judge the prognosis of patients. Of course, the more projects, the more expensive they are, and the more information they provide. But in fact, not all lung cancer patients need genetic testing. For example, my classmate's father, lung carcinoma in situ, the surgical cure rate is 100%, do not need any postoperative treatment, genetic testing is not too necessary.
In terms of staging, stage 0 carcinoma in situ and stage IA micro-invasive carcinoma surgery is 100% cured, and genetic testing is not required. Stage IA patients do not need to do any adjuvant therapy, including targeted therapy, after surgery according to the guidelines for lung cancer diagnosis and treatment. In theory, genetic testing is not required. However, in stage IA, especially stage IA3, which has more risk factors, some patients may have relapse and metastasis in subsequent years, and genetic testing can be done according to the wishes of their families. On the one hand, patients use targeted drugs according to their own wishes and detection conditions, on the other hand, some patients have difficulty in obtaining specimens by puncture biopsy again after recurrent metastasis, and genetic testing can also guide the use of targeted drugs in future recurrent metastasis.
For patients with lung adenocarcinoma above stage IB, genetic testing is routinely required, because the sensitive gene mutation rate of mainland adenocarcinoma patients is relatively high, and there is a greater chance that targeted drugs can be used, and the guidelines have also been updated last year, recommending Adjuvant Targeted Therapy after surgery for patients with IB and above, and EGFR mutation-positive patients are preferably opted for ossigninib.
Therefore, for postoperative large pathology for adenocarcinoma, patients above stage IB routinely need to do genetic testing, and patients with postoperative large pathology for squamous cell carcinoma can not do genetic testing of 12 targets, because the current targeted therapy-related driver genes mainly occur in adenocarcinoma, but it is recommended to do PDL1, TMB, MSI and other immunotherapy-related indicators to guide follow-up immunotherapy.
For patients with advanced lung cancer, if it is a small specimen obtained by puncture or tracheoscopy, genetic testing must be done to confirm the diagnosis of adenocarcinoma. Squamous cell carcinoma or small cell lung cancer, depending on the economic situation, can be considered for genetic testing. Because there is too little tissue in the small label, it may not reflect the state of the overall tumor tissue, such as some mixed tumors, both squamous cell carcinoma and adenocarcinoma components, or small cell carcinoma components, at this time the tissue taken does not necessarily completely cover the real type of tumor. If there is a combination of adenocarcinoma components, it may also benefit from targeted drugs.
Because squamous cell carcinoma is relatively effective in immunotherapy, advanced squamous cell carcinoma patients are recommended to target immunotherapy because if PDL1 is highly expressed (PDL1>49%), immune monotherapy can play a good role.
In terms of the choice of genetic testing methods, if it is a large postoperative specimen, a generation of ARMS method can be selected, covering 10-15 genes, and the price is low. For advanced patients, due to the difficulty of repeatedly taking materials, it is recommended to choose a second-generation NGS test, a one-time detection of many genes, but the price is expensive. In addition, blood draws and thoracoascial fluid exfoliation cells can also be tested for NGS, and this method can also be considered in patients who cannot obtain specimens.