Abstract Background: Lipomas are most frequent benign soft tissue tumours with incidence of about 6 %. For giant lipoma, chest wall is the rare site. Extension in the thoracic cavity is unique. No case of chest wall lipoma with extension in thoracic cavity is reported. Case presentation: We report a rare case of left anterior chest wall lipoma in 45 year old man for 15 years. It had extension in the thoracic cavity. On CT scan, its size was 145mm x 132mm x 90mm and in the chest cavity it was 119mm x 60mm x 72mm size. Patient had minimum symptoms. Core biopsy confirmed the benign nature. Surgical excision under GA was done. Recovery was uneventful. Histopathology report confirmed as "Giant Lipoma". Conclusion: Giant lipoma of the anterior chest with extension into thoracic cavity is a rare presentation. Even with such large size, they can give minimum symptoms. Proper pre-operative assessment of such large lesions is very important for proper management.

Keywords: Giant Lipoma, chest wall, benign tumour, Case Report