Case Report

Year : 2026 | Volume : 10 | Issue : 1 | Page : 18-22

Malignant Transformation of an Odontogenic Cyst into Primary Intraosseous Squamous Cell Carcinoma: A Case Report

Case report

1*Private practitioner, Oral Medicine and Radiology (Radiologist), Western Academic Health Center, Navi Mumbai, Belapur- 400 614 India.

Email: Priyasharma1995134@gmail.com

Abstract

Introduction: Primary intraosseous squamous cell carcinoma (PIOSCC) is a rare odontogenic malignancy that develops within the jaw bones without an initial connection to the oral mucosa. Malignant transformation of an odontogenic cyst into PIOSCC is an uncommon event and presents significant diagnostic challenges because its clinical and radiographic features often resemble those of benign odontogenic lesions. Case presentation: We report a rare case of PIOSCC arising from an odontogenic cyst in a 58-year-old male who presented with a progressively enlarging swelling in the left posterior maxillary region associated with intermittent pain and discomfort during mastication. Clinical examination revealed an exophytic ulceroproliferative lesion involving the maxillary alveolar ridge with associated soft tissue swelling and surface erythema. Panoramic radiographic evaluation demonstrated a radiolucent lesion affecting the posterior maxilla with evidence of cortical bone destruction and extension toward the adjacent maxillary sinus, suggesting an aggressive pathological process. Histopathological examination of the incisional biopsy revealed a cystic lesion lined by odontogenic epithelium exhibiting focal epithelial dysplasia and a distinct transition from benign cyst lining to invasive malignant squamous epithelium. High-power microscopic examination demonstrated invasive nests and islands of atypical squamous epithelial cells showing marked cellular pleomorphism, nuclear hyperchromatism, increased nuclear-cytoplasmic ratio, and keratin pearl formation, consistent with well-differentiated squamous cell carcinoma. Correlation of the clinical, radiographic, and histopathological findings established the diagnosis of primary intraosseous squamous cell carcinoma arising from an odontogenic cyst. Conclusion: This case emphasizes the importance of careful clinicopathological evaluation and meticulous histopathological examination of odontogenic cysts for early detection of malignant transformation and timely therapeutic intervention, thereby improving patient prognosis and long-term clinical outcomes.                                                                                                    

Acknowledgment

Nil

Conflict of interest

Nil

Source of funding

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How to cite this article: Priya Sharma,. Malignant Transformation of an Odontogenic Cyst into Primary Intraosseous Squamous Cell Carcinoma: A Case Report,, Int J Clinicopathol Correl. 2026; 10(1):18-22. 10.56501/Int.J.Clin.Pathol.Correl.10.1.ijcc0139.Copyright © 2026 Priya Sharma.