Giant Cell Tumor of Bone of the First Rib Successfully Treated with Combined Preoperative Denosumab Therapy and Surgery via a Transmanubrial Approach

Abstract

BACKGROUND Giant cell tumor of bone (GCTB) is a locally aggressive, intermediate tumor that rarely metastasizes. GCTB typically affects the ends of long bones and rarely involves the ribs. Curettage is typically the treatment of choice for GCTB in long bones. However, the optimal treatment of GCTB in ribs remains unclear. We report the case of a patient with asymptomatic GCTB of the first rib that was successfully treated with combined preoperative denosumab therapy and surgery via a transmanubrial approach without resection of the clavicle. CASE REPORT A healthy 27-year-old woman presented with a bone tumor involving the left first rib that was incidentally discovered on routine chest X-ray. Histological examination of core-needle biopsy specimens of the lesion led to a pathological diagnosis of GCTB. After preoperative denosumab treatment for 6 months, en bloc resection via a transmanubrial approach was performed. There were no serious postoperative complications. The patient remained free of symptoms and had no recurrence 4.5 years after surgery. CONCLUSIONS Compared with other ribs, masses located in the first rib can be challenging to treat surgically because of the clavicle and neighboring neurovascular structures. This report is the first to describe GCTB located on the anterior aspect of the first rib that was successfully treated with combined preoperative denosumab therapy and surgery via a transmanubrial approach, with no recurrence or functional impairment of the shoulder girdle.

Figure 1.

Chest X-ray examination shows a lesion on the left first rib (arrow).

Figure 2.

Chest computed tomography shows an osteolytic mass arising from the anterior arc of the first rib.

Figure 3.

(A) T1-weighted and (B) T2-weighted magnetic resonance images show an axial view prior to denosumab therapy. (C) T1-weighted and (D) T2-weighted magnetic resonance images at 4 months after denosumab therapy.

Figure 4.

Microscopic images of the tumor specimen prior to denosumab therapy (hematoxylin and eosin staining). The tumor demonstrates diffuse proliferation of multinucleated, osteoclast-like giant cells and uniform ovoid- to spindle-shaped mononuclear stromal cells.

Figure 5.

Computed tomography images 6 months after starting denosumab therapy. (A) Axial view. Significant tumor shrinkage and calcified sclerotic rim compared with pretreatment images (Figure 2). (B) Sagittal view. (C) Coronal view. (D) Three-dimensional reconstruction of computed tomography arteriography shows the subclavian artery passing between the tumor of the first rib and clavicle.

Figure 6.

(A) Skin incision (thin solid line), L-shaped sternal division (thick solid line), and release of the sternal head and the clavicular head of the sternocleidomastoid muscle from its origin (dashed line) are illustrated. (B) Gross specimen and pathological findings. The tumor in the first rib was resected. The tumor (arrow) was covered by smooth pleura. (C) A microscopic view shows diffuse proliferation of short, spindle-shaped cells without nuclear atypia, as well as osteoid formation and extensive fibrosis throughout the entire specimen. No giant cells are observed (hematoxylin and eosin staining).