How to treat lung metastasis of rectal cancer

After rectal cancer metastasizes to the lungs, the fewer the number of lung metastases and the longer the interval between primary lesion resection and lung metastasis resection, the higher the survival rate. Many clinical literatures have reported that lung metastasis resection can improve survival rates and suggest expanding surgical indications. But besides surgical treatment, what other treatments are there for rectal cancer metastases to the lungs?

Surgical treatment

When colorectal cancer CRC develops lung metastasis, it often means that the disease has reached the stage of widespread dissemination, and only a small number of patients can receive surgical treatment. Factors that affect the prognosis of lung metastasis resection include the number of lesions, primary tumor stage, disease-free interval, preoperative CEA level, hilar or mediastinal lymph node metastasis, etc. A single lesion, a disease-free interval of more than 36 months, and a normal preoperative CEA level indicate a good prognosis, while patients with hilar or mediastinal lymph node metastasis have a poor prognosis. Its main indications are: (1) ≤3 metastatic lesions; (2) well-differentiated tumors, because poorly differentiated tumors are more likely to cause extensive metastasis; (3) >1 cm tumor-free margin; (4) no other unresectable extrapulmonary metastases; (5) sufficient cardiopulmonary function.

The number and size of metastases are also related to prognosis. Pfannschmidt reported that the 5-year overall survival rate of 167 CRC patients with complete resection of lung metastases was 34.4%, of which 45% were for patients with single lung metastases and 19.8% were for patients with multiple lung metastases, with a significant difference. Patients with normal preoperative CEA levels have a better prognosis. Lee reported that the 5-year overall survival rate of a group of patients was 50.3%, and the 5-year survival rates of patients with elevated and normal CEA were 22.7% and 48.3%, respectively. If lung metastases recur after the first complete resection, surgery can be performed again. Ogata reported that the efficacy of re-surgical resection was similar to that of the first resection.

Radiofrequency ablation

Radiofrequency ablation is a good treatment option for patients with unresectable CRC lung metastases.

Terence et al. reported that 100 patients with inoperable CRC lung metastases had a median survival of 36 months and a 5-year survival rate of 30% after radiofrequency ablation. Multivariate analysis showed that radiofrequency ablation efficacy, repeated ablation, extrapulmonary metastasis, and adjuvant chemotherapy were significantly associated with prognosis. The main complications were pneumothorax, pleural effusion, and pneumonia, and there were no treatment-related deaths.

Treatment of unresectable pulmonary metastases

For CRC patients with unresectable lung metastases, neoadjuvant chemotherapy should be given as much as possible to convert unresectable lesions into resectable ones. Neoadjuvant chemotherapy regimens can include FOLFOX, FOLFIRI or CapOx, etc., and bevacizumab or cetuximab can also be added (KRAS wild type, KRAS mutant can use new drugs such as Androidjian, selumetinib, etc.), and the chemotherapy time is generally 2 to 3 months. Among them, bevacizumab should be discontinued 6 weeks before surgery and can be used again 6 to 8 weeks after surgery. Neoadjuvant chemotherapy can downstage the primary tumor and shrink the metastatic lesions. It can also detect the sensitivity of the tumor to chemotherapy, so that tumors that are insensitive to chemotherapy can benefit more from the resection of metastatic lesions. Adjuvant chemotherapy can be continued after surgery, and the preoperative and postoperative chemotherapy time is preferably half a year. Immediate surgery is only required when patients have acute complications such as intestinal obstruction, perforation, and bleeding. Most patients can relieve symptoms within the first 1 to 2 weeks of chemotherapy, and the risk of the above complications during chemotherapy is low.

The above are common treatment methods for lung metastasis of rectal cancer. In addition, rectal cancer patients have undergone repeated treatments, some of which have poor efficacy and lack confidence in treatment. Most of them will experience fear, anxiety, irritability, pessimism and negative mentality. In view of their psychological reactions, nursing should be patient and explanations should be in place to help them build confidence in overcoming the disease.