Malignant Transformation Associated with Endometrioid Adenocarcinoma: A Rare Case Report
Introduction
Endometriosis, a condition characterized by the presence of endometrial glands and stroma outside the uterine cavity, affects approximately 176 million women worldwide. While it is considered a benign disease, a small percentage of endometriosis patients (0.7% to 1%) are at risk of developing malignancy. The concept of malignant transformation associated with endometrioid adenocarcinoma (AWE) is a rare and complex phenomenon, often challenging to diagnose and manage.
Case Presentation
We present a rare case of secondary AWE (subsequent to a cesarean section) that underwent malignant transformation into endometrioid adenocarcinoma. The patient, a 39-year-old female, noticed a progressive abdominal mass over four months. Her medical history included a left lung teratoma surgery 20 years ago and a cesarean section six years ago, with no family history of malignant tumors. Physical examination revealed a cesarean section scar and a palpable mass in the left lower abdominal wall.
Imaging studies, including abdominal ultrasound and CT scans, showed a cystic-solid mass in the lower abdomen, suspected to originate from mesenchymal tissue. Tumor markers, such as CA125, CEA, CA199, CA153, SCC, and HE4, were elevated, indicating potential malignancy. The patient underwent laparoscopic exploration, abdominal wall mass resection, and abdominal wall plastic surgery.
Pathology revealed highly differentiated adenocarcinoma with squamous cell features, consistent with endometrioid carcinoma. Immunohistochemistry demonstrated positive staining for CKpan, partially positive staining for CK7, PAX-8, Vimentin, and CD10, and weakly positive staining for CDX-2. The patient's postoperative course was complicated by wound healing issues, and adjuvant chemotherapy was administered.
Discussion
Malignant transformation of AWE, particularly endometrioid adenocarcinoma, is a rare occurrence. The pathogenesis of endometriosis and its malignant transformation is complex and multifactorial. Studies suggest a correlation between genetic mutations and the development of endometriosis-associated malignancy (EAM).
Genetic mutations, such as PTEN, ARID1A, CTNNB1, and RAS, play significant roles in the malignancy of endometriosis. These mutations contribute to the activation of downstream signaling pathways, leading to the onset and progression of EAM. The coexistence of benign lesions and malignant tumor tissues in certain cases supports the hypothesis that endometriosis and EAM share a comparable 'tissue environment'.
Clinical Manifestation and Auxiliary Examination
AWE patients typically present with abdominal wall nodules or masses, often accompanied by pain. Ultrasound is a commonly used imaging method due to its convenience and cost-effectiveness. MRI provides high-resolution images, while CT scans can detect metastases in various regions. Elevated CA125 levels are typically observed in EAM, but in AWE, levels are usually normal or slightly elevated, making it a less reliable marker for diagnosing malignant transformation.
Pathological Features
The predominant pathological pattern of EAOC is endometrioid adenocarcinoma. However, clear cell carcinoma is the most frequently reported type of AWE. Immunohistochemical staining, combined with pathological features, can improve the accuracy of diagnosing endometrioid adenocarcinoma. Typical endometrioid morphology is characterized by densely packed glands with sparse interstitium.
Treatment and Post-Treatment Monitoring
There is no consensus on the optimal surgical and postoperative approach. Wide resection is the current common treatment for AWE. Hysterectomy, bilateral adnexectomy, and inguinal lymph node dissection are often recommended. Adjuvant chemotherapy and radiotherapy may be administered post-surgery.
Conclusion
Preventive measures, such as reducing cesarean section rates and incision protection, are crucial to minimize iatrogenic endometrial implantation. The assessment of abdominal wall masses requires a comprehensive approach, including clinical and radiological information, biopsy, and histopathology. Surgical management should consider the patient's fertility preferences.
Ethic Approval and Consent to Participate
Written informed consent was obtained from the patient, and ethics committee approval was granted.
Consent for Publication
All authors consented to the publication of this case report.
Acknowledgments
We express our gratitude to all contributors and supporters of this study.
