Biochemical markers of bone metabolism are some of the final product which are released into the blood during the process of bone resorption or bone formation.Accumulative evidence shows that biochemical markers of bone metabolism through enzyme-linked immunoassay (ELISA) are more sensitive and specific than imaging examination.Moreover,biochemical markers of bone metabolism also display their superiorities on the early diagonosis,monitoring efficacy and prognosis evaluation in patients with bone metastases.Applications of biochemical markers of bone metabolism combined with imaging examination are more value for the early diagonosis,monitoring efficacy and prognosis evaluation in patients with bone metastases.

Bone-modifying agents (BMA) is a series drugs to alleviate the pain,pathological fractures,spinal cord compression,hypercalcemia,bone-related events which induced by bone metastases.Bisphosphonate drugs and denosumab are two dominant kinds of BMA at present.It has been proved that BMA is used in bone metastases patients with bone destruction,as adjuvant therapy for chemotherapy and radiotherapy,which can significantly improve the efficacy and prolong the survival of patients.In addition,some traditional Chinese medcine can effectively relieve a series of related symptoms caused by bone metastases and improve prognosis.Choosing right medication in clinical work can maximize the reduction of pain caused by bonerelated events and improve the quality of life of patients.

The lymphatic metastasis affects prognosis and survival of colorectal cancer seriously,and lymphangiogenesis plays an important role in the lymphatic metastasis. Many factors such as COX-2 and MMP-7 which are found in many researches recently can promote the expression of VEGF-C which can promote the lym-phangiogenesis by connecting with its receptor and activating the relevant signal pathway. At present,as these related factors of lymphangiogenesis are found in colorectal cancer,the process of lymphangiogenesis in colorec-tal cancer becomes more clear,but the exact mechanism of these factors needs to be researched in future.

Objective:To investigate the values of serum neuron specific enolase (NSE), circulating tumor cells (CTC) and lactate dehydrogenase (LDH) levels in the diagnosis and treatment of small cell lung cancer (SCLC).Methods:Ninety patients with SCLC who received treatment in the Second Affiliated Hospital of Zhejiang Chinese Medical University, China between December 2017 and December 2019 were retrospectively included in the observation group. Ninety healthy subjects who concurrently received lung examination in the same hospital were included in the healthy control group. An additional 90 patients with benign lung disease were included in the benign lung disease group. Serum NSE, CTC and LDH levels were determined in each group. The values of serum NSE, CTC and LDH levels in the diagnosis of SCLC were analyzed. Serum NSE, CTC and LDH levels were compared between before and after chemotherapy and their values in the treatment of SCLC were analyzed.Results:There were significant differences in serum NSE, CTC and LDH levels between three groups ( F = 359.789, 188.873 and 768.704, all P < 0.001). Serum NSE, CTC and LDH levels in the benign lung disease group were significantly greater than those in the healthy control group and significantly lower than those in the observation group. The receiver operating characteristic curve (ROC curve) analysis showed that the AUC values of serum NSE, CTC and LDH levels in the diagnosis of SCLC were 0.995, 0.953 and 0.987, respectively. The diagnostic accuracy was very high. The value at the maximum tangent point of Youden's index of serum NSE, CTC and LDH levels at the left-upper corner of the ROC curve was taken as the most appropriate cut-off value. The sensitivity and specificity of the most appropriate cut-off value of serum NSE, CTC and LDH levels in the prediction of SCLC were 100.0%/94.4%/91.1% and 94.4%/88.3%/100.0%, respectively. Therefore, serum NSE, CTC and LDH levels were of high values in the predication of SCLC. After chemotherapy, serum NSE, CTC and LDH levels in patients with SCLC were significantly lower than those before chemotherapy [NSE: (12.26 ± 3.26) μg/L vs. (18.36 ± 4.64) μg/L; CTC: (3.54 ± 1.08) counts/5 mL vs. (7.34 ± 1.30) counts/5 mL; LDH: (24.61 ± 9.66) U/L vs. (50.29 ± 16.29) U/L, t = 10.205, 12.864, 21.330, all P < 0.001). Serum NSE, CTC and LDH levels in SCLC patients in whom treatment was effective were significantly lower than those in SCLC patients in which treatment was not effective ( t = 8.111, 7.347, 10.731, all P < 0.001). Spearman correlation results showed that serum NSE, CTC and LDH levels were significantly negatively correlated with curative effects ( r = -0.562, -0.562, -0.758, all P < 0.05). Conclusion:Serum NSE, CTC and LDH levels are highly expressed in SCLC patients, which can be used as markers for early clinical diagnosis and treatment of SCLC.