Classification and related information of lung cancer

Lung adenocarcinoma carcinoma in situ, micro-invasive adenocarcinoma and invasive adenocarcinoma are all early lung cancer.

The basis of pathological differentiation is the growth stage, pathological characteristics and postoperative recurrence rate of early lung cancer. It has important guiding significance for the treatment of ground glass nodules.

According to the definition of the International Association for Lung Cancer Research (ISLAC) (Figure 1), AIS is the earliest tumor with adherent alveoli. CT findings are pure ground-glass nodules, 5-30mm, without solid components (Figure 2). Theoretically, AIS does not break through the basement membrane and will not transfer. AIS does not affect life, and may not grow for a long time (years or even decades), so AIS does not need surgery.

MIA is a further development of A is, which is defined as that the scope of tumor breaking through basement membrane is less than 5mm, and CT findings are ground glass nodules less than 30mm, containing solid components less than 5 mm (Figure 3). The growth of MIA is similar to A is, but the possibility of tumor metastasis is very small, because very few tumors have broken through the basement membrane. Postoperative recurrence is rare, and the recurrence rate is about 1% within 5 years. Therefore, MIA can consider surgery, but the risk of surgery itself needs to be considered, and the necessity of surgery is not strong.

However, invasive adenocarcinoma IAC is very different. IAC is the further development of AIS and MIA, and its growth speed is accelerated. CT showed mixed ground glass nodules with solid content greater than 5 mm (Figure 4). As the basement membrane of tumor mutation increases, the risk of metastasis and recurrence begins to appear, which may affect the overall life span. According to the size of solid components (5- 10 mm, 10-20 mm, 20-30 mm), the 5-year survival rate of IAC was 92%-77% (Figure 5).

In order to protect life to the greatest extent, once the ground glass nodule is likely to develop into IAC, surgical resection can be considered after weighing the surgical risks. Therefore, the key to diagnose ground-glass nodules is to identify IAC. According to the definition, only the mixed ground glass nodules with solid components greater than 5mm on CT are IAC. However, the current research suggests that pure ground glass nodules may also be IAC. This requires our grading model of ground glass nodule infiltration to distinguish IAC from ground glass nodule, so as to guide the necessity of operation.

Small cell lung cancer almost occurs in smokers (98% patients have a history of smoking), especially in heavy smokers, and rarely occurs in non-smokers. Quitting smoking or not smoking can greatly reduce the risk of small cell lung cancer.

The proportion of small cell lung cancer in all lung cancers has decreased, accounting for about 15% of all lung cancers.

Although lung cancer can metastasize to other organs, small cell lung cancer may metastasize faster, and the symptoms of patients' metastasis develop faster than those of non-small cell lung cancer.

Because of the invasion of small cell lung cancer, the examination needed for staging should not delay the treatment; Otherwise, many patients may get worse during the interval between examination and treatment, accompanied by a significant decline in physical condition (PS). Therefore, once the pathology confirms that it is small cell lung cancer, it is necessary to complete the examination of definite stages as soon as possible and start treatment as soon as possible.

In the past, the staging system of small cell lung cancer mainly adopted the limited stage and extensive stage of Veterans Lung Cancer Research Group (VASLG). At present, TNM staging is gradually applied to small cell lung cancer.

Localized small cell lung cancer accounted for 1/3 at the time of initial diagnosis, mainly concurrent radiotherapy and chemotherapy; Extensive stage accounts for about 2/3 of small cell lung cancer, mainly chemotherapy.

Only less than 5% of patients with small cell lung cancer may be suitable for surgical treatment, and more than 95% of patients with small cell lung cancer are mainly treated with radiotherapy and chemotherapy.

Because the doctor who is newly diagnosed with small cell lung cancer is also a surgeon, please remember to consult the radiotherapy and chemotherapy doctor through the clinic after confirming that the pathology is small cell lung cancer.

Although more than 60 drugs failed in clinical trials of small cell lung cancer, SLCL is called "the tomb of new drug research and development". But in recent years, some progress has been made in drug research and development, including immunotherapy and targeted therapy.

Thoracic surgeon information

Professor Wu Yilong, chief physician.

Guangdong Provincial People's Hospital. Lung surgery

Guangdong Provincial People's Hospital. oncology department

Professor Jianxing He, chief physician.

The first affiliated hospital of Guangzhou medical university eye protection hospital-thoracic surgery

References:

[1] What are the differences among adenocarcinoma in situ (AIS), microinvasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC)? The handling is very different!

[2] Understand the diagnosis, pathology, staging, radiotherapy and chemotherapy of small cell lung cancer (1)

[3] To understand the diagnosis, pathology, staging and treatment of small cell lung cancer mainly treated by radiotherapy and chemotherapy (part two)

[4] Classification and pathology of lung cancer

[5]? What are AIS and MIA in the lungs?