To our best knowledge, this was the first study comparing the post-operative outcomes and costs with the most comprehensive cost analysis between VATS lobectomy and open lobectomy among Chinese patients with lung diseases, regardless of lung cancer status. The post-operative outcomes of VATS lobectomy were significantly better than open lobectomy. And this was the first study assessing risk factors for high hospitalization costs of lobectomy operation in Chinese population. Overall, total hospitalization costs among the patients with VATS lobectomy were similar to open lobectomy. However, the total non-surgery costs were significantly lower in VATS compared to open lobectomy.
Our findings were consistent with the previous studies [4, 7, 9, 17, 18]. First, post-operative clinical outcomes including blood transfusion, lung infection, and post-operative LOS were all significantly better in the VATS lobectomy group, comparing with the open lobectomy group. It indicated that minimally invasive technology indeed reduced the complications. Second, the procedure costs, cartridge costs for VATS lobectomy was significantly higher, it may be due to the advanced technology of VATS lobectomy. Blood costs, drug costs and hemostatic material costs in the open lobectomy group were significantly higher, it might result from a relatively greater trauma from open lobectomy approach. A study also found hospitalization costs in VATS lobectomy group were significantly higher due to higher operative and instrument costs, compared with open lobectomy approach [18]. The GLM regression results showed that the total hospitalization costs were associated with post-operative lung infection, post-operative LOS, gender, lung cancer diagnosis status, and heart disease.
Long-term survival from these two approaches was also evaluated in the previous studies. Most study findings showed the long-term survival was comparable between open lobectomy and VATS lobectomy [19–24]. We did not include this as a measurement as the clinical outcomes in our study. The main reason was that either VATS or open lobectomy could lead to blood loss, infection, and physical pain, however, significant bleeding during lung resection surgery was found to be rare in a retrospective matched cohort analysis using real-world data [25]. Thus, we did not consider the complications from either lobectomy approach to significantly increase death from the procedure. In addition, many other aspects including post-operation recovery, development of other comorbidities, cancer upstage, or cancer reoccurrence might have even a bigger impact on the long-term survival. Other ways to measure the clinical safety and effectiveness of VATS lobectomy can also include readmission due to the lobectomy surgery complications in a short-term period post the hospital discharge, which can further affect the overall hospitalization costs [26].
Many previous studies have applied the PSM to control the inherent biases in non-randomized comparison [4, 27–30], common parameters for matching from previous studies included age, gender, smoking history, body mass index, American Society of Anesthesiologists (ASA) Risk Scale, Eastern Cooperative Oncology Group (ECOG) score, surgical side, tumor size, histological type, preoperative chemotherapy or radiotherapy, and comorbidities such as hypertension, coronary artery disease, cardiac failure, diabetes, and cerebrovascular disease. However, propensity score matching can only match on the observables. It cannot manage the differences in unobservable variables, and it may still introduce selection bias.
In our study population, patients in open lobectomy group and VATS lobectomy group were similar, except for the gender distribution. More males received open lobectomy, while more females received VATS lobectomy. It may be because more males were smokers, with worse pulmonary function, and with advanced lung cancer. Thus, open lobectomy might be more appropriate in this situation, as it would be safer and more likely to remove the whole tumor [31]. However, gender was not an important factor for the difference in complication rates between these two lobectomy approaches, it might still introduce selection bias without a propensity score matching (PSM) to control the difference. In addition, many of the controlled variables from previous studies were not available from the dataset we used. Gender was the only variable that was differently distributed in the study population. And it was not the most important factor that would lead to the difference in complication rates between the two approaches. Thus, PSM was not chosen in our approach. The lack of clinical pre-operative characteristics, such as smoking history, more comorbidity types, pulmonary function that may have impact on the complication rates, were not available. And we were unable to appropriately control the non-randomized selection bias was another limitation.
There were some additional limitations in our study. First, either open lobectomy or VATS lobectomy requires surgeons to have sufficient training and experience, and it plays an important role in the assessment of complications and hospitalization costs, as the economic impact could be magnified as the surgeons’ experience increases [5]. Surgeons with limited experience in open lobectomy can achieve satisfactory outcomes in VATS lobectomy comparable to their more experienced seniors [32]. Thus, without the consideration of surgeons’ experience, the interpretation of the comparison between open lobectomy and VATS lobectomy might be biased. Second, this study used medical records for a single hospital. Due to the unbalanced development of the thoracic surgery technology in different regions in China, the study population may not be representative for the target population.
More assessments are still needed in the future. A more comprehensive list of comorbidities and pre-operative pulmonary function should be included and matched. Different measurements for clinical outcomes, such as patient-reported outcomes, readmission rate, need be considered. In the meantime, indirect medical costs due to loss of productive time should be considered from the societal perspective.