In this study, 127 patients with bone metastases from lung cancer admitted to our hospital from October 1997 to January 2007 were followed up. Among them, 84 were male and 43 were female, with a mean age of 61.2 years (29-88 years). Among the 127 patients, 17 (13.4%) had single bone metastases and 110 (86.6%) had multiple bone metastases. A total of 141 surgical sites were completed, including 93 spine surgeries and 48 limb surgeries; the surgical boundaries of tumor resection in limb surgeries reached extensive or marginal resection in 23 cases and intra-focal resection in 25 cases. The cumulative survival rate at 1 year after bone metastasis of lung cancer was 25.8%. The survival rate of patients with single bone metastasis was better than that of patients with multiple lesions, and there was no significant difference in the survival rate depending on the surgical border and the way of tumor resection. Defining the prognostic factors of patients with bone metastases from lung cancer can help determine the indications for surgery and further improve the treatment outcome and survival of patients with bone metastases from lung cancer. Understanding the prognostic factors related to bone metastases is very important to standardize the treatment of bone metastases. Numerous scholars have proposed corresponding prognostic factor assessment systems for the treatment of bone metastatic cancer. Most of the studies are based on various common types of tumors that are prone to bone metastases, such as lung cancer, breast cancer, prostate cancer, kidney cancer and thyroid cancer. It is well known that the 5-year survival rate of lung cancer is only 10-20%, and the prognosis is extremely poor. Bone metastasis is the third most common metastatic site of lung cancer, after liver metastasis and intrapulmonary metastasis. Bone metastases from lung cancer can cause serious complications such as pain, pathological fractures and spinal cord compression, which can reduce patients’ quality of life and affect their prognosis. 30-40% of lung cancer patients with bone metastases were reported by Coleman et al. We retrospectively studied the clinical data of a group of patients with bone metastases from October 1997 to January 2007 to investigate the clinical prognostic factors of patients with bone metastases from lung cancer, in order to help guide the treatment of patients with bone metastases from lung cancer. I. Materials and methods: We reviewed 127 patients with bone metastases from lung cancer who could be followed up, including 84 males and 43 females, with a male-to-female ratio of 1.95:1; the average age was 61.2 years (29-88 years), admitted to the Department of Bone Oncology, Peking University People’s Hospital between October 1997 and January 2007. the basic conditions of the patients are shown in Table 1. lung cancer The diagnosis was based on chest X-ray and lung CT, fiberoptic bronchoscopy or lung surgery; the site and number of bone metastases were determined based on the patient’s X-ray plain film and whole-body isotope bone scan; in order to clarify the involvement of other organs (mainly brain, liver, adrenal gland and intra-pulmonary), the commonly used examinations included cranial CT, abdominal ultrasound or whole-body PET-CT. Among 127 patients with bone metastases Among the 127 patients with bone metastases, 17 (13.4%) had single bone metastases, 110 (86.6%) had multiple bone metastases, and 86 (67.7%) had metastases to other organs. 47 patients (37%) had bone metastases at the time of first diagnosis of lung cancer or were diagnosed as bone metastases from lung cancer after examination of the first diagnosis of bone destruction. The pathological type of tumor was non-small cell lung cancer in 106 cases (83.5%), of which 80 cases (63.0%) were adenocarcinoma, 17 cases (13.4
(63.0%), 9 cases of large cell carcinoma (7.1%), and 21 cases of small cell lung cancer (16.5%). The patients’ general survival status was assessed by applying the ECOG Performance Status Scoring (EPS), in which 5 cases had a PS score of 0, 23 cases had a PS score of 1, 27 cases had a PS score of 2, 29 cases had a PS score of 3, and 43 cases had a PS score of 4. The general survival status of patients with preoperative PS scores of 2-4 was assessed to improve after surgery, in which the PS scores The general survival of patients with preoperative PS scores of 2-4 was evaluated. At the time of presentation, 23 patients had pathological fractures of the limbs and 47 patients had pathological compression fractures of the spine with (or without) paraplegia. All 127 patients underwent surgery for metastatic sites, 135 times, including 48 limb site surgeries and 87 spine site surgeries. 44 patients underwent resection of primary lung cancer tumors, including 37 cases with bone metastases after radical lung cancer surgery at the primary site, and 7 cases who underwent lung tumor resection after bone metastases were found, all of which were single bone metastases without metastases to other organs All of them were single bone metastases without other organ metastases; 95 cases (74.8%) received chemotherapy and 93 cases (73.2%) received radiotherapy. SPSS12.0 statistical software was applied to analyze the prognostic factors, including gender, age, general survival status (ECOG survival status score), pathological subtype, number of metastases (single, multiple), presence of other organ metastases, duration of metastases, relevant treatment received (radiotherapy, chemotherapy), presence of orthopedic complications (pathological fracture of limbs or acute paraplegia of the spine ), etc. The Kaplan-Meier survival curve and Cox survival correlation model were used to analyze the univariate and multifactorial correlations of the factors affecting the patients’ survival. II. RESULTS: The median survival time of 127 patients with lung cancer was 10.6 months, and the median survival time after the appearance of bone metastases was 6.7 months, and the mean time to the appearance of bone metastases after the diagnosis of lung cancer was 3.9 months in this group. Kaplan-Meier curves were applied to show the overall survival of 127 patients with bone metastases from lung cancer. Among all the factors analyzed, it was observed that the effective prognostic factors included the survival status of the patients (ECOG survival status score), the pathological subtype of the tumor, the number of bone metastases, the first diagnosis of bone metastases, the presence of metastases from other organs, the duration of metastasis (time from the first diagnosis of lung cancer to the appearance of bone metastases), and orthopedic complications. Among them, ECOG survival status score (0-1), single bone metastasis without metastasis from other organs was the factor of good prognosis; among the pathological subtypes of patients, the best prognosis was squamous carcinoma, followed by large cell carcinoma, and the worst prognosis was adenocarcinoma and small cell carcinoma; while first diagnosis bone metastasis (first diagnosis lung cancer with bone metastasis or bone destruction as the first pathological confirmation of lung cancer bone metastasis), the presence of metastasis from other organs, and Duration of metastasis (time interval between the first diagnosis of lung cancer and the appearance of bone metastasis) ≤ 4 months, and orthopedic complications (presence of pathological fracture or paraplegia due to spinal cord compression) were factors suggesting poor prognosis. The patient’s gender, age, and previous treatment (radiotherapy, chemotherapy) had little effect on the patient’s prognosis. COX multifactor regression analysis was performed for each of these relevant factors, and the results were obtained as follows (Table 3), excluding the interfering effects of the prognostic factors that affect each other. From this, we can see that among the factors related to the prognosis of bone metastases from lung cancer that we studied, the main co-influential factors that determined the prognosis of patients included the pathological subtype of patients, general condition (ECOG score), the number of metastases (single, multiple, other organ metastases), and the time interval from the first diagnosis of lung cancer to the appearance of bone metastases in patients. III. Discussion: It is a well-known fact that the study of prognostic factors of primary tumors and the establishment of staging systems (such as TNM staging, Enneking staging, etc.) are useful for guiding tumor treatment. However, for bone metastases, there are many aspects of prognostic factors and the establishment of prognostic scoring systems that deserve further investigation. Harrington et al. proposed a classification scheme to guide surgical intervention for bone metastases in the spine: 1) no significant neurological involvement; 2) vertebral bone involvement without bone collapse or instability; 3) significant nerve damage (sensory or motor nerves) without significant bone loss; and 4) significant nerve damage without significant bone loss. Harrington believes that patients in categories 1-3 can receive chemotherapy, endocrine therapy, and/or local radiation therapy without surgical intervention; patients in categories 4-5 require surgical intervention; and The prognostic scoring system established by Tokuhashi et al. for the preoperative evaluation of patients with metastatic spine cancer, and the scoring system for metastatic spine cancer proposed by Tomita et al. and the surgical treatment strategy based on this system have become the basis for guiding the surgical treatment of metastatic spine cancer [4]. The aim is to further guide the rational treatment of tumor bone metastases.
The common risk factors associated with the prognosis of metastatic cancer include the primary site of the tumor, the general condition of the patient, the status of metastases (including the number and presence of visceral metastases), the sensitivity to prior treatments (e.g., chemotherapy, radiotherapy), and the presence of orthopedic complications (e.g., acute paraplegia, pathological fractures). Most studies are based on various common types of tumors that are prone to bone metastases, such as lung cancer, breast cancer, prostate cancer, kidney cancer, and thyroid cancer. We believe that the clinical manifestations, metastatic pathways and final prognosis of bone metastases from different types of tumors are very different, and should be studied differently. In our study, we analyzed the follow-up data of lung cancer bone metastasis patients in our department in the past ten years and summarized the prognostic factors related to these patients in order to guide the rational clinical treatment. The sites of tumor bone metastasis usually involve the mid-shaft bone first, followed by the femur and humerus, and rarely involve the distal limb. Coleman et al. suggested that the bone metastases of lung cancer are more likely to occur in the chest and spine, which may be related to the following factors: (1) the chest is the closest to the primary site of lung cancer, which is easy to metastasize directly; (2) the lymphatic vessels of the lung have direct or indirect traffic with the lymphatic vessels of the rib cage, and these lymphatic vessels enter the thoracic duct or directly invade the pulmonary veins to enter the body circulation to form (3) the blood circulation in the chest is abnormally rich, and the chance of cancer cells metastasizing through blood is greatly increased; (4) the spine metastasizes earlier than the pelvis, and the common reason may be related to the direct invasion of lung cancer into the thoracic spine, coupled with the rich network of veins without valves with slow blood flow beside the spine, which gives cancer cells the opportunity and time to stay here; (5) the bone tissues in the pelvis, limbs and head, which are far from the primary site of lung cancer, mainly further development of bone metastases [8]. The general condition of the patient (ECOG score) is an important factor suggesting the prognosis of patients with bone metastases from lung cancer, and Tokuhashi and Tomita et al. used the general condition of the patient as an important factor in assessing the prognosis of metastatic cancer in the spine. We believe that the general status score in patients with metastatic cancer of the extremities has the same suggestive effect on prognosis. We compared the prognosis of patients with a PS0-1 score with those with a PS2-4 score, and there was a significant difference.