Via Research Recognition Day Program VCOM-Carolinas 2025

Case Reports

Pleomorphic pulmonary carcinoma of the lung with osteoclast-like giant cells: A case report Christopher Goddard, OMS-IV 1 *, Charles Rousseau, DO 2

1. Edward Via College of Osteopathic Medicine-Carolinas Campus, Spartanburg, SC 2. Spartanburg Regional Healthcare System, Department of Surgery, Spartanburg, SC

Discussion

Introduction

Hospital Course and Outcome

Lung cancer is a major cause of morbidity and mortality causing 125,000 deaths in 2024 1 . Lung carcinoma with osteoclast-like giant cells (OGCs) is one exceedingly rare subtype. First described in 1963, less than fifteen cases have been reported. Due to their morphologic similarity to the cells in giant cell tumors of the bone, OGCs can cause clinical confusion when observed in other organs potentially leading to an initial misdiagnosis as metastatic disease or a benign inflammatory response, rather than association with a primary tumor 2 . A 64-year-old female with a 40-pack-year smoking history underwent lung cancer screening revealing a left lower lobe lobulated lesion measuring 3.9 x 4.1 x 4.3 cm (Figure A). 18F-FDG PET/CT showed the lesion crossing the major fissure with avid uptake and a SUV max of 23.2 (Figure B). CT-guided needle biopsy showed clusters of multinucleated giant cells staining immunohistochemically positive for CD68 and SATB2 and focal necrosis without definitive evidence of carcinoma (Figure C). Staging video mediastinoscopy with sampling of mediastinal lymph node stations 2R, 4R, 4L, and 7 failed to show evidence of neoplastic cells. Left-sided video assisted thoracoscopy was performed for further tissue biopsy revealing a malignant osteoclast-like giant cell-rich neoplasm of uncertain histogenesis favoring carcinoma. Surgical resection was recommended to the patient who chose to delay treatment due to social issues. Case Report

References • First reported case of pleomorphic pulmonary carcinoma (PPC), a poorly differentiated non-small cell lung carcinoma, composed entirely of spindle cells, neoplastic giant cells, and osteoclast-like giant cells. PPC is aggressive showing early metastasis, high recurrence rates, and invasion into nearby structures 3 • Pleomorphic pulmonary carcinoma responds poorly to chemotherapy or radiotherapy, making surgical resection the most favored treatment modality 4 . • OGCs are benign cells and do not show evidence of altering prognosis of the primary cancer 2, 5 . • Several immunohistochemical markers have been identified on OGCs such as CD68, vimentin, and TRAP. • Future research should attempt to identify unique biomarkers present on these cells to prevent misdiagnosis as metastatic disease. 1.Siegel, R. L., Giaquinto, A. N., & Jemal, A. (2024). Cancer statistics, 2024. CA: A Cancer Journal for Clinicians, 74(1), 12 – 49. https://doi.org/10.3322/caac.21820 2.Leung, & Morava ‐ Protzner. (1998). Large cell carcinoma of lung with osteoclast ‐ like giant cells. Histopathology, 32(5), 482 – 484. https://doi.org/10.1046/j.1365-2559.1998.0358f.x 3.Raveglia F, Mezzetti M, Panigalli T, Furia S, Giuliani L, Conforti S, Meda S. Personal experience in surgical management of pulmonary pleomorphic carcinoma. Ann Thorac Surg. 2004 Nov;78(5):1742-7. doi: 10.1016/j.athoracsur.2004.04.084. PMID: 15511465. 4.Chang Y.L., Lee Y.C., Shih J.Y. Pulmonary pleomorphic (spindle) cell carcinoma: peculiar clinicopathologic manifestations different from ordinary non-small cell carcinoma. Lung Canc. 2001;34:91 – 97. doi: 10.1016/s0169-5002(01)00224-0. 5.Dahm, H. H. (2016). Non – small cell carcinoma of the lung with osteoclast-like giant cells. International Journal of Surgical Pathology , 25 (3), 258 – 261. https://doi.org/10.1177/1066896916679519

Repeat 18F-FDG PET/CT four months later revealed an interval increase in lesion size to 6.3 x 5.9 cm (Figure D). • Surgery: Left thoracotomy with lower lobectomy, left upper lobe en bloc posterior segmentectomy, and excision of lymph node stations 5, 7, 9L, 10L, 11L, and 12L. • Specimen: 12.0 x 7.5 x 7.0 cm, pale-tan, fleshy, lobulated, and rubbery. Interspersed yellow necrotic, friable areas focally invading and obstructing the adjacent bronchus. All margins negative for invasive carcinoma. No lymph node metastasis. • Pathology: Pleomorphic carcinoma composed entirely of spindle cells and malignant giant cells with osteoclast-like giant cells. • Follow-up: Chest CT at two months post-op did not show evidence of tumor recurrence The patient remains under close surveillance. A B

C

D

Figure A. Initial low-dose screening CT scan. 3.9 x 4.1 x 4.3 cm left lower lobe lesion. Figure B. ¹⁸F -FDG PET/CT showing increased uptake with an SUV max of 23.2. Figure C. Multinucleated giant cells present in the tumor sample. Figure D. 18 F-FDG PET/CT showing interval increase of the left lower lobe lesion to 6.3 x 5.9 cm.

2025 Research Recognition Day

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