Salvage resection via a trans-manubrial approach after definitive chemoradiotherapy for initially unresectable thymic carcinoma in the superior mediastinum: a case report

Introduction

Thymic carcinoma is a rare disease that more frequently presents as unresectable at initial diagnosis compared to thymoma. There is limited data on patients undergoing salvage resection after chemotherapy, radiotherapy, or chemoradiotherapy. Although salvage resection after definitive chemoradiotherapy for unresectable thymic carcinoma remains controversial, complete resection may still be achievable. Herein, we report a successful salvage resection via a trans-manubrial approach following definitive chemoradiotherapy for initially unresectable thymic carcinoma, with discussion of radiological and pathological findings. We present this article in accordance with the CARE reporting checklist (available at https://med.amegroups.com/article/view/10.21037/med-2025-1-69/rc).

Case presentation

A 48-year-old man with hoarseness was diagnosed with thymic squamous cell carcinoma, which appeared to invade the aortic arch and arch vessels (Figure 1A), the trachea, and the esophagus, with metastasis to a left supraclavicular lymph node (LN) [T4N2M0, Union for International Cancer Control 9th edition tumor-node-metastasis (TNM) staging], with high programmed cell death ligand-1 (PD-L1) expression. His past medical history was unremarkable. The preoperative diagnosis was established by ultrasound-guided biopsy of the supraclavicular LN. The tumor was initially considered unresectable due to an invasion to the trachea, the esophagus, the aortic arch, and the arch vessels. He received definitive chemoradiotherapy with two cycles of nab-paclitaxel (100 mg/m² on days 1, 8, and 15) in combination with carboplatin (target area under the curve of 5), plus 60 Gy, resulting in a partial response (PR) on computed tomography. At completion of the 2 cycles, the patient and the referring physician discussed salvage surgery to manage presumed residual disease on computed tomography (Figure 1B), and he was referred to our institution. After extensive discussion with the patient regarding resection versus observation, we proceeded with salvage surgery, with an interval of two months from completion of chemotherapy. The patient understood the difficulty in assessing viable cells in case of a radiologically residual lesion after definitive chemoradiotherapy, as well as the difficulty of performing re-biopsy due to the small lesion size.

Figure 1 CT findings. (A) Pre-chemoradiotherapy CT image showing a superior mediastinal tumor with suspected invasion of the left subclavian artery (indicated by arrows). (B) Post-chemoradiotherapy CT image demonstrating a residual lesion (indicated by arrows). CT, computed tomography.

Under general anesthesia with a double-lumen endotracheal tube, the patient was positioned supine. The femoral area was exposed in preparation for potential use of cardiopulmonary bypass. Salvage surgery was performed via a left-sided trans-manubrial approach, in an attempt to resect the primary lesion with potential replacement of the aortic arch vessels (Video 1). Dissection started with thymectomy, followed by dissection of the aortic arch and its branches. Subsequently, the tumor tissue was dissected from the trachea and esophagus using an electrocautery (Figure 2A), then from the thoracic vertebrae using a sealing device. The left recurrent laryngeal nerve could not be identified within the scar tissue incorporated into the tumor mass. Finally, the tumor was separated from the left common carotid artery and the left subclavian artery (Figure 2B). Intraoperative LN dissection was performed at subaortic and paraaortic stations. The operative time was 5 hours and 2 minutes; no transfusion was needed. The postoperative course was uneventful. The entire tumor bed was submitted for histological examination and histopathology showed no viable tumor cells in the resected specimen (pTXN0M0). At 32 months postoperatively, the patient remains alive with no evidence of disease.

Figure 2 Intraoperative findings. (A) The tumor tissue being dissected from the trachea and the esophagus. (B) Dissection of the tumor from the aortic arch vessels.

All procedures performed in this study were in accordance with the ethical standards of the institutional research committee and with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient for publication of this case report and accompanying images and video. A copy of the written consent is available for review by the editorial office of this journal.

Discussion

To our knowledge, four patients aged 31 to 61 years have been reported to undergo salvage surgery after chemotherapy (n=1), radiotherapy (n=2), and combined chemoimmunotherapy and radiotherapy (n=1) (1-3). There were no cases of operative mortality among these patients. The resected specimens revealed no viable tumor in one patient (3) and residual viable tumor in another (2), whereas histopathological details were not provided for the remaining two cases (1). Regarding long-term outcomes, one patient had recurrence-free survival (RFS) for 3 years (2), another had 9 months of RFS (3), while detailed survival information was unavailable for the other two patients (1).

This report highlights that a residual lesion in the superior mediastinum can be effectively approached using a trans-manubrial approach, followed by meticulous dissection of the trachea, esophagus, and arch vessels after definitive chemoradiotherapy. The superior mediastinum is a relatively broad anatomical space bounded inferiorly by the transverse thoracic plane—an imaginary line extending from the sternal angle to the lower border of the fourth thoracic vertebral body (T4). We acknowledge that median sternotomy is the standard approach for the aortic arch and arch vessels, whereas access to the trachea and esophagus may be more readily obtained via a trans-manubrial approach. We were prepared to extend the incision to a median sternotomy if replacement of the aortic arch became necessary.

Radiologically residual lesions after definitive chemoradiotherapy do not always correlate with histopathological findings. In this report, we emphasize that a radiologically persistent lesion after such treatment does not necessarily indicate the presence of viable tumor cells, although we proceeded with salvage surgery for potentially residual microscopic diseases on the basis of post-treatment computed tomography. Among the four previously reported cases of salvage resection for thymic carcinoma, two patients underwent both radiological and pathological evaluation after definitive chemotherapy or chemoimmunotherapy (1). One patient achieved a radiological PR after chemotherapy, yet viable tumor cells were identified in the resected specimen (2). In contrast, another patient achieved a radiological complete response after chemoimmunotherapy, and no viable tumor cells were found pathologically, as in our patient (3). Little information was available regarding optimal radiological modalities to evaluate any residual diseases, however, multiple modalities such as computed tomography (CT), positron emission tomography (PET), and/or magnetic resonance imaging (MRI) may contribute to improved patient selection for salvage surgery.

Because only a limited number of cases have been reported, the indications, optimal timing, and long-term benefits of salvage surgery for thymic carcinoma after definitive non-surgical treatments remain unclear. Salvage surgery in this setting should be performed at experienced centers with multidisciplinary expertise.

Conclusions

A trans-manubrial approach in salvage surgery provided a less invasive yet effective exposure for a residual lesion in the superior mediastinum. Radiological assessment of any residual disease after definitive chemoradiotherapy was challenging.

Acknowledgments

The outline of this article was presented at the 105^th annual meeting of the American Association for Thoracic Surgery.

Footnote

Reporting Checklist: The authors have completed the CARE reporting checklist. Available at https://med.amegroups.com/article/view/10.21037/med-2025-1-69/rc

Peer Review File: Available at https://med.amegroups.com/article/view/10.21037/med-2025-1-69/prf

Funding: None.

Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://med.amegroups.com/article/view/10.21037/med-2025-1-69/coif). M.H. serves as an unpaid editorial board member of Mediastinum from January 2026 to December 2027. The other author has no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional research committee and with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient for publication of this case report and accompanying images and video. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

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