Fresia Juwitasari Wongkar¹, Prilly Astari² 

¹ Department of Anatomical Pathology, Bethsaida Hospital, Tangerang, Indonesia 

² Department of Obstetrics and Gynaecology, Bethsaida Hospital, Tangerang, Indonesia 

Introduction: Endometriosis in the abdominal wall following a caesarean section is an uncommon occurrence, accounting for only 0.03%-1.5%.¹ Regenerative skeletal muscle cells in endometriosis can sometimes be florid, making the diagnosis more challenging. 

 

Case description: The first case was a 36-year-old female with intermittent pain and a mass in the anterior abdominal wall over the past three months. The second case was a 33-year-old female with an enlarged mass in the anterior abdominal wall and experienced cyclic pain starting 3 days before menstruation. Both patients had a history of caesarean sections. Microscopic showed endometrial glands and stroma between skeletal muscle tissue. There are also hemosiderophages and clusters of polygonal cells with abundant cytoplasm, with one to multiple nuclei resembling rhabdoid cells and multinucleated giant cells. No mitosis was identified. Immunohistochemical staining was not performed. Based on histopathology examination, we conclude that this patient has endometriosis with regenerative skeletal muscle cells. 

Conclusion: Skeletal muscle cells undergo regenerative changes following injury and can resemble neoplastic lesions.²Understanding the histopathology of regenerative skeletal muscle cells, along with the use of immunohistochemistry and clinical correlation, is helpful in establishing a diagnosis. Pathologists must be aware of this entity to avoid misdiagnosing it as a neoplastic lesion, ensuring appropriate management can be provided. 

Keywords: endometriosis, regenerative skeletal muscle, caesarean section 

Statement of Originality: We declare that the manuscript represent our original idea and contribution. We acknowledge that it has not been previously published elsewhere. 

 

References 

1. Mirza R, Abdulsattar J, Cotelingam J. Endometriosis Associated Striated Muscle Changes : Simulating Tumor. Hindawi Case Reports Pathol. 2021;2021(6666283):1–4. 

2. Colella R, Mameli MG, Bellezza G, Sordo RD, Cavaliere A, Sidoni A. Endometriosis-associated skeletal muscle regeneration: a hitherto undescribed entity and a potential diagnostic pitfall. Am J Surg Pathol. 2010 Jan;34(1):10-7.