Giant pelvic-perineal leiomyoma simulating a malignant lesion

Introduction: Soft tissue tumors are benign or malignant lesions developing from connective tissue and its varieties. Case Report: A 35-year-old patient referred to us for management of a voluminous pelvic-perineal mass. The clinical and para clinical data were in favor of a malignant lesion. The treatment consisted of a wide excision of the tumor. The post-operative period was complicated by an anal incontinence needing a protective left iliac colostomy. A perinioraphy, sphincter refection, and re–establishment of the digestive continuity were performed later on. The cytological examination of the excised mass revealed a conclusive involute hyanilised leiomyoma. Conclusion: This contrast between the clinical, para clinical and histologic data in our patient confirm the diagnostic challenges of soft tissue tumors, hence the need for special technic to assure diagnostic certitude to avoid mutilating surgical approaches for a benign lesion.


Introduction
Soft tissue tumors are benign or malignant lesions developing from connective tissue and its differentiated varieties which are adipose tissue, muscular tissue, vascular tissue, synovial and fascial, as well as the tissue enveloping nerve peripheral cells [1].
The benign tumors are a 100 times more frequent than malignant ones [2,3]. However, faced with a soft tissue tumor, the first objective is to think of a sarcoma of the soft tissue.
We report a case of a voluminous pelvic-perineal mass. The clinical and para-clinical data were in favor of a malignant lesion contrasted by cytological examination which revealed a benign tumor, the leiomyoma type.

Case report
A case report of a 35 years old female presented at the surgical department for the management of a voluminous tumor of the pelvicperineal area which developed for a period of about 4 years. This mass caused a lot of discomfort in the sitting position, wearing clothing, and sexual relationships as result causing psychosocial problems.
The patient had undergone an excision of the same mass 4 years ago. This surgery was followed by a recurrence of the tumor. A cytological examination was not done.
On admission in our hospital the patient was in good general condition. Physical examination demonstrated a flabby, non-tender mass, measuring 24 cm the widest diameter, emanating from the left buttocks with an anal extension and at the level left labia majora ( Figure 1). The pelvic exam revealed a bulging into the left cal de sac. We did neither notice any urinary or sphincter problems.

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Case Report

. Journal of Surgical Case Reports and Images
Papa Abdoulaye Bâ *

Figure 1: Tumor genito-gluteal, front view
The CT scan suggested a tumoral process with a progressive potential impact to the genital region invading in an obstructive way the ureters, the bladder the rectum. Magnetic resonance imaging showed a voluminous multi lobular pelvicperineal mass suggestive of an angioma, schwanoma or a sarcoma ( Figure 2). The treatment was surgical and consisted of wide excision of the tumor with partial section of the external anal sphincter, the levator ani and coccygeal hamstrings muscles. Repair of muscle, sphincter, by advancement and rotation skin flaps was performed. The post-operative period was complicated by an anal incontinence needing a protective left iliac colostomy. A perinioraphy, sphincter refection, and re-establishment of the digestive tube continuity were performed later on. The outcomes were favorable with good anal continence and complete healing. Cytological examination of the surgical specimen concluded an involute hyalinized leiomyoma (Figure 3).

Figure 3: Microscopic view of the tumor.
After a period of 4 years, there has been no recurrence ( Figure 4).

Discussion
Leiomyomas are rare tumors as evidenced by the series of 1331 benign soft tissue tumors published by Myhre-Jensen where they represent only 3.8% [4]. They are cutaneous or superficial tumors originating from the erector muscles of hair follicles in particular areas of extension of the limbs or smooth muscle present in the deep dermis, in the genital areas.
In the work of Wibner [5], nearly 60% of soft tissue tumors are located at the extremities and the genital location in the second place. In our patient, the localization was the base of the lower limb at the buttocks and genital extension.
Clinically, the tumoral, painless syndrome is the most frequent reason for seeking consultation in the series of Ackerman, 50% [6]. This painless character explains the delay in seeking consultation.
Auctores Publishing -Volume 4(4)-071 www.auctoresonline.org ISSN: 2690-1897 Page 4 of 4 Enziger and Weiss have shown that there is no consistent safe proof extract from the examination that can distinguish between benign and malignant, showing the difficulty in diagnosis of these tumors [3].
MRI provides major topographic and semiological arguments but is not specific enough for the diagnosis of malignancy.
Tumors with a diameter greater than 50 mm, and the height greater than 66 mm, are often suspicious for malignancy [7].
Thus in our patient, MRI having found a multi-layered lesion measuring 31 cm high, 26 cm anterior-posterior diameter and the transverse axis of 18 cm suggests a potentially progressive tumor. However, definitive diagnosis remains a matter of histology [8].
Wide excisions should be preferred instead of marginal resections which are always inadequate, more so intracapsular resections that are nothing else than simple surgical biopsies [9].
For our part, despite clinical and para clinical data suggestive of malignancy, there was no evidence of mitotic activity at microscopy of the surgical specimen which is in favor of a leiomyoma.
Recurrence observed in our patient after an initial excision is probably due to incomplete excision.

Conclusion
Soft tissues tumors present themselves in form of a painless, tissular mass. Management is best decided in a specialized collegial type manner, given the rarity, multiple histological types and possible clinical presentations. This will reduce misdiagnosis and avoid mutilating surgery in case of benign lesion.

Conflict of interest
Authors declare no conflict of interest.