Abstract
Background: The development of a mass in a surgical scar poses a diagnostic dilemma due to similarities in appearance to hernias, abscesses, hematomas or desmoid tumors. Scar endometriosis is uncommon and malignant change within this ectopic tissue is rare. Case Report: The case of a 55-year-old woman with an isolated clear cell adenocarcinoma in an area of scar endometriosis more than 17 years after a cesarean section is presented. Initially, this tumor was thought to be a chronic abscess, but was finally diagnosed as clear cell carcinoma. This case highlights the difficulties in preoperative diagnosis as well as the poor prognosis of these tumors. Conclusion: Accurate diagnosis of a lump within a scar is important to define the prognosis and treatment. Further data are needed for the management of this pathology.
Case Report
A 53-year-old gravida 4, para 4 woman presented with increasing pain in her cesarean section scar over two years. She had no major health problems and her only surgery was a cesarean section for complete placenta previa during her fourth pregnancy in 1988. Her gynecological history revealed dysmenorrhea, deep dyspareunia and cyclical pain in her abdominal scar during menses, starting immediately after the surgery. She had been in menopause for two years and had never taken hormonal therapy.
She described the current pain as a constant dull ache located in the incision, with progressive augmentation in volume of a nodule within the scar in the previous four months. When she consulted her family practitioner, the lesion had the appearance of a chronic abscess and she was referred to a general surgeon for removal. A 2.5 cm nodule was removed under local anesthesia and much granulation tissue was noted, as well as abundant frothy material, but no foreign body or suture was found. Final pathology showed a clear cell carcinoma of probable ovarian origin and the patient was referred to the gynecological oncology service.
Upon clinical evaluation, there was an indurated 5 cm lesion in her scar and there was evidence of infection at the operative site with purulent discharge. The patient also had prominent bilateral inguinal adenopathy. Pre-operative workup revealed a CA-125 level of 39 kU/L, normal chest radiography and an MRI showed a 4.7×4.3 cm implant in her abdominal scar with multiple external iliac nodes reaching 2 to 3 cm in size. Her left ovary demonstrated a 10×8 cm mass characteristic of a dermoid cyst.
At laparotomy, a wide local excision of the abdominal scar was performed, along with peritoneal cytology, total hysterectomy, bilateral salpingo-oophorectomy, omentectomy, pelvic lymph node dissection and bilateral inguinal lymphadenectomy. Other than the mass at the incision, the enlarged pelvic and inguinal lymph nodes and the dermoid cyst, all surfaces and organs were free of disease and no intra-abdominal endometriosis was noted.
Final pathology revealed extensive infiltration with clear cell carcinoma in the abdominal wall with a positive inferior margin, 10/14 positive pelvic nodes and 17/17 positive inguinal nodes. The uterus, apart from a grade 3 cervical intraepithelial lesion (CIN III), demonstrated only adenomyosis. The right ovary and omentum were normal. The left ovary showed a mature teratoma (dermoid cyst). No endometriosis was noted in the specimen.
The postoperative period was uneventful and the patient received 4 of 6 intended cycles of carboplatin with paclitaxel every 21 days beginning 13 days after surgery. The patient did not wish to continue her treatment because of fatigue and was not compliant with follow-up. Three months after surgery, she consulted with increasing supra-pubic pain and swelling. Her physical examination revealed a 3 cm right inguinal node and a 1 cm lesion in her abdominal scar, both suspect for recurrence. A computed tomograpy scan of the abdomen also revealed many enlarged pelvic nodes. Biopsy of the right inguinal node was positive for clear cell carcinoma, consistent with a recurrent disease. Pelvic irradiation was proposed, which the patient refused.
Malignant transformation of endometriosis in a parietal scar.
Six weeks later, she was admitted with increasing nausea, vomiting and alteration of consciousness. Renal failure secondary to obstruction was diagnosed. An abdominal scan revealed an 8×8 cm mass in the pelvis and many enlarged lymph nodes. Many suspect mediastinal nodes were noted on the thoracic scan and a brain scan was normal. The patient was given palliative care and rapidly deteriorated. She died 2 weeks after admission, exactly 11 months following her initial diagnosis of cancer.
Discussion
Abdominal wall clear cell carcinoma is a rare phenomenon. The most probable explanation is malignant transformation of endometriotic foci within the abdominal scar. Some authors have demonstrated the presence of endometriosis either in coexistence with the carcinoma, or immediately preceding its development. Even when Sampson's criteria (1) for endometriotic malignant transformation cannot be met, it is still possible that the tumor has arisen from peritoneum trapped in the abdominal scar during the laparotomy (2), that it is a metastasis from an intra-abdominal carcinoma (2), or that the endometriosis has simply been completely invaded by carcinoma (2).
In our case, although the histopathology does not fulfil Sampson's criteria, it is presumed that clear cell carcinoma had arisen from an endometrial focus. The patient had classic symptoms of endometriosis until menopause, including cyclical pain in her scar during menses beginning shortly after her cesarean section. Endometriosis is common in women of childbearing age and scar endometriosis has been well described (3). Approximately 1% of endometriotic lesions are found in sites of previous incisions (3). Endometriosis in the abdominal wall following cesarean section has a reported prevalence of 0.03% (4). There seems to be a clear association between endometriosis and cancer. Although the evidence supporting an association between the two conditions is weak, with strength of association ranging between 1.3 and 1.9 (5), there is reason to believe that in some cases there is progression from endometriosis to carcinoma, especially when endometrioid or clear cell types are considered. Fever than 1% of women known to have endometriosis will develop an endometriosis-related cancer (6). Furthermore, only 5% of carcinomas arising in ectopic endometriosis are of clear cell histology (7, 8). Although intraperitoneal malignant transformation of endometriosis is well described, development of cancer in a distant site such as at the abdominal wall is very rare. Taking into consideration this data, the overall probability of having endometriosis in a cesarean section scar and having this endometriosis subsequently undergo malignant transformation into a clear cell carcinoma without any ovarian pathology is infinitely small. Few other similar cases have been reported to date (Table I).
In conclusion, it must be remembered that any enlarging nodule or increasing pain within an abdominal scar may potentially be secondary to malignancy. Abnormalities in surgical scars, even in the absence of intra-abdominal pathology, should not be ignored. Diagnosis must be promptly made by fine-needle aspiration (2), or biopsy of the tumor. In the event of a malignancy, the optimal management is undefined because of the limited published data. Further research in this area is warranted and encouraged. It is proposed that a strategy similar to that recommended for advanced ovarian cancer should be adopted, starting with an optimally cytoreductive surgery followed by chemotherapy, with the addition of tumor-directed radiotherapy as needed.
- Received August 6, 2008.
- Revision received December 30, 2008.
- Accepted January 19, 2009.
- Copyright© 2009 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved
