Surgery for malignant pulmonary nodules in patients with a history of oesophageal cancer

Are Incidental Minute Pulmonary Nodules Ultimately Determined to Be Metastatic Nodules in Esophageal Cancer Patients?

PURPOSE

Esophageal cancer patients may simultaneously have resectable esophageal cancer and undiagnosable incidental minute solid pulmonary nodules. While the latter is rarely metastatic, only a few studies have reported on the outcomes of such nodules after surgery. In this retrospective study, we assessed the incidence of such nodules, the probability that they are ultimately metastatic nodules, and the prognosis of patients after esophagectomy according to the metastatic status of the nodules.

METHODS

Data of 398 patients who underwent esophagectomy for resectable esophageal cancer between January 2012 and December 2016 were collected. We reviewed computed tomography (CT) images from the first visit and searched for incidental minute pulmonary nodules <10 mm in size. We followed the outcomes of these nodules and compared the characteristics of metastatic and nonmetastatic nodules. We also assessed the prognosis of patients whose minute pulmonary nodules were metastatic.

RESULTS

Among the patients who underwent esophagectomy, 149 (37.4%) had one or more minute pulmonary nodules, with a total of 285 nodules. Thirteen (4.6%) of these nodules in 12 (8.1%) patients were ultimately diagnosed as being metastatic. Thirteen (8.7%) patients experienced recurrence at a different location from where the nodules were originally identified. Characteristics of the metastatic nodules were not unique in terms of size, SUVmax, or location in the lungs. Two-year and 5-year overall survival rates of patients whose nodules were metastatic were 64.2 and 32.1%, respectively.

CONCLUSION

The rate of minute pulmonary nodules which were ultimately metastatic was 4.6%. Our findings suggest that esophagectomy followed by the identification of minute pulmonary nodules is an acceptable strategy even if the nodules cannot be diagnosed as being metastatic on the first visit CT due to their small size.

Preoperative evaluation and indications for pulmonary metastasectomy

Pulmonary metastasectomy (PM) is an established treatment that can provide improved long-term survival for patients with metastatic tumor(s) in the lung. In the current era, where treatment options other than PM such as stereotactic body radiation therapy (SBRT), immunotherapy, and molecular-targeted therapy are available, thoracic surgeons should review the approach to the preoperative evaluation and the indications. Preoperative evaluation consists of history and physical examinations, physiological tests, and radiological examinations. Radiological examinations serve to identify the differential diagnosis of the pulmonary nodules, evaluate their precise number, location, and features, and search for extra thoracic metastases. The indication of PM should be considered from both physiological and oncological points of view. The general criteria for PM are as follows; (I) the patient has a good general condition, (II) the primary malignancy is controlled, (III) there is no other extrapulmonary metastases, and (IV) the pulmonary lesion(s) are thought to be completely resectable. In addition to the general eligibility criteria of PM, prognostic factors of each tumor type should be considered when deciding the indication for PM. When patients have multiple poor prognostic factors and/or a short disease-free interval (DFI), thoracic surgeons should not hesitate to observe the patient for a certain period before deciding on the indication for PM. A multidisciplinary discussion is needed in order to decide the indication for PM.

The short-term outcomes of pulmonary metastasectomy or stereotactic body radiation therapy for pulmonary metastasis from epithelial tumors

Background

Stereotactic body radiation therapy (SBRT) has recently been widely performed for relatively small-volume tumors. We analyzed the short-term outcomes of pulmonary metastasectomy (PM) or SBRT for pulmonary metastases.

Methods

This study was a retrospective analysis of 82 patients with pulmonary metastasis from epithelial tumors who underwent PM or SBRT between 2013 and 2016.

Results

Fifty-nine patients underwent PM, 21 patients underwent SBRT, and 2 patients underwent combined PM and SBRT. The mean age of the PM group was significantly lower than that of the SBRT group (60.6 vs 67.4 years, p = 0.03). The most frequent types of primary tumor in the PM and SBRT groups were colorectal cancer (n = 27, 46%) and head and neck squamous cell carcinoma (n = 8, 38%), respectively. The rate of treatment-associated complications did not differ between the two groups to a statistically significant extent (20% vs 24%, p = 0.76). The 3-year local control rates of the two groups were similar (PM group, 88%; SBRT group, 92%; p = 0.48). The 3-year progression-free survival (PFS) rate of the PM group were better than that of SBRT groups (42% vs 11%, p = 0.01). The 3-year overall survival (OS) rates of the PM and SBRT groups were 77 and 52% respectively; although the rate of the PM group was higher, the difference was not statistically significant (p = 0.10).

Conclusions

SBRT provides a favorable 3-year local control rate. The 3-year OS rate of the SBRT group tended to be lower than that of the PM group, despite the difference was not statistically significant. PM and SBRT play complementary roles in patients with pulmonary metastases.

Proposal of a Useful Surrogate Endpoint of the Overall Survival in Patients Undergoing Pulmonary Metastasectomy: The Time to Local Therapy Failure

BACKGROUND

A recent study demonstrated remarkable discrepancy between the relapse-free survival (RFS) and overall survival (OS) after pulmonary metastasectomy (PM) in the current era. As the RFS may not be a suitable parameter after PM, a more suitable parameter is needed for PM as a surrogate marker for OS.

METHODS

A total of 134 consecutive patients who underwent PM were retrospectively analyzed. In the present study, we introduced a new endpoint, time to local treatment failure (TLTF). This endpoint was defined as the time interval between the first PM and the first untreatable recurrence by local treatment with curative intent or death due to any cause. We analyzed the correlation between the RFS and OS and between the TLTF and OS to validate whether or not the TLTF is a better parameter than the RFS after PM.

RESULTS

Thus far, 78 patients have experienced relapse. Of these, 37 patients (47%) underwent local therapy with curative intent, 29 of whom are alive without local treatment failure. The 5-year OS, RFS and TLTF were 70.9%, 36.5%, and 57.6%, respectively. The concordance proportions for the RFS and OS and for the TLTF and OS were 0.634 and 0.851 for all patients, respectively. The Spearman's rank correlation coefficient for the RFS and OS was 0.639, while that for the TLTF and OS was 0.875.

CONCLUSIONS

The TLTF may be a good surrogate parameter for the OS after PM in the current era.