Aggressive angiomyxoma of the female pelvis and the labium

İngilizce (OpenAlex)

Aggressive angiomyxoma is an extremely uncommon neoplasm of the female pelvis and perineum. In 1883, Virchow first introduced the entity of soft tissue myxomata (1). A century later in 1983, Steeper and Rosai presented nine cases of a distinctive soft tissue tumor in the female genitalia and pelvic soft tissues, and termed it ‘aggressive angiomyxoma’ (AAM) (2). Approximately 94 cases had been described until 1996, and Fetsch et al. reported the largest series of AAM (3). Despite its benign histological appearance, although it does not metastasize, AAM demonstrates a pronounced tendency for aggressive local, often multiple recurrences (4). It is histologically characterized by a predominantly myxoid stroma and an abundance of thin- and thick-walled vascular channels (5). In our first case, isolated labial AAM including pedicle was 45 × 15 × 7 cm, which was the largest in the labial area, whereas, in literature, the largest size was reported to be 60 × 20 cm in the pelvic gluteal region (6). In literature, there is no evidence that AAM originating from Douglas' pouch extended into the abdomen. We herein report two cases of this rare condition. The first one was the largest labial AAM, and the second orginated from Douglas' pouch and extended into the abdomen. A 38-year-old woman presented with a painless vulvar mass (right labium majus) that slowly enlarged during the past 2 years. On physical examination, a right labial pedunculated mass including pedicle, approximately 45 × 15 × 7 cm in size and 850 g in weight, was revealed. The length of the mass extended over the knee in the upright position (Fig. 1). The lesion was excised under local anesthesia. Macroscopically, the tumor was tan-colored, and partially covered by normal skin; it was soft, gray-white, myxomatous homogeneous on cut section. Histopathologic examination demonstrated the presence of stellate and spindle-shaped neoplastic cells embedded in a collagenous and myxoid stroma; and a prominent vascular component with blood vessels of variable caliber spread in this myxoid stroma (Fig. 2). There were no nuclear atypia and virtually no mitotic activity. Immunohistochemical examination revealed immunoreactivity of the stromal cells for vimentin (Fig. 3). The stromal cells were negative for desmin and alpha-smooth muscle actin. Pericytes and vascular smooth muscle were positive for alpha-smooth muscle actin (Fig. 4). All these findings revealed the diagnosis ‘aggressive angiomyxoma’. Two years later, no recurrence had occurred. The postoperative result was cosmetically and functionally acceptable (Fig. 5). A 38-year-old woman with a painless vulvar mass (right labium majus) slowly enlarging within 2 years. Proliferation of stellate and spindle-shaped stromal cells were scattered in a mixoid stroma, and numerous blood vessels of varying caliber were present (H & E ×100). Stromal cell showing positive staining for vimentin (immunoperoxidase, ×100). The stromal cells do not stain for alpha-smooth muscle actin whereas the pericytes are well stained; (a) immunoperoxidase, ×100; (b) immunoperoxidase, ×200. Postoperative result was cosmetically and functionally acceptable. A 50-year-old woman suffering from a large pelvic cystic mass, abdominal swelling and pain was admitted to our Gynecology service. Routine gynecologic and pelvic ultrasound found a gross simple cystic bulky mass extending upward 10 cm above the umbilicus. Transabdominal and transvaginal ultrasound confirmed that the uterus and ovarium were normal (Fig. 6). CA 125, CEA, CA 19-9, CA15-5 levels analysis was normal. Preoperative diagnosis was considered to be serous cystadenoma of the ovary. Ten days later, during laparotomy, we found a mass measuring approximately 25 × 16 × 9 cm. It was originated from Douglas' pouch, extending upwards to the upper abdomen. The tumor was composed of cystic and solid components. The solid component included soft and gelatinouse tissues. It was uncapsulated, and retroperitoneally infiltrating into the surrounding soft tissues. The upper portion of this tumor was a large cystic mass and encapsulated. The tumor was extirpated totally. The frozen section at the time of surgery showed that tumor was benign. Total abdominal hysterectomy and bilateral salpingooophorectomy were prophylactically performed. Histopathologic examination presented numerous thin- and thick-walled blood vessels of varying caliber, spindle-shaped and stellate neoplastic cells in a myxoid to collagenous stroma. Immunohistochemical findings were similar to those of the first case. The diagnosis was considered to be ‘aggressive angiomyxoma’. One year later, there was no evidence of recurrence. A mass measuring approximately 25 × 16 × 9 cm in size was extirpated during laparotomy. In 1883, Virshow described for the first time the entity of soft tissue myxomata. A century later in 1983, Steeper and Rosai presented a distinctive variant of myxoid neoplasm occurring in the female pelvis, vagina and perineum, which they termed AAM (1,3). Aggressive angiomyxoma is an extremely rare, but well-described neoplasm. It is a distinctive tumor with a characteristic clinical course and specific gross and microscopic features. AAM is a locally infiltrative, but non-metastasizing, lesion mainly involving the vulvar and perineal region of women and girls during the reproductive years (3,6–8). Yet, there is no consensus about the origin of AAM, but the special stroma lower genital tract is suspected (9). There are no criteria that reliably predict the behavior of these lesions. It is difficult to establish a clear relationship between size and the risk of recurrence based on the small number of cases reported, many with inadequate follow-up data (4). In our cases, there was no evidence of recurrence. Actually recognition of recurrence is important to ensure careful clinical follow-up, as AMM is a widely infiltrative tumor (4). Both cases have been followed up. Clinically, the lesions were characterized by a mass infiltrating the soft tissues of the female pelvis and perineum. Velanovich et al. proposed that three types of angiomyxomas identified were superficial angiomyxoma, aggressive angiomyxoma, and angiomyofibroblastoma. Although all three share many histological features, these lesions are pathologically and clinically distinct (10,11). Granter et al. discussed three entities under distinct topics, and reported that AAM should be differentiated from superficial angiomyxoma, and angiomyofibroblastoma (4). He also differentiated AAM from other myxoid tumors. He also pointed out that AAM and angiomyofibroblastoma were members of a spectrum of related tumors showing myofibroblastic differentiation. This tumor has a dominant myxoid histological pattern, prominent vascularity, slow growth (12). Histopathologically, the tumor is probably derived from myofibroblasts, and tends to be firm, poorly encapsulated gelatinous masses that locally infiltrate the soft tissues. It consists of myofibroblastic cells and prominent blood vessels within a myxoid stroma (13). In our two cases, histopathologic examination demonstrated the presence of stellate and spindle-shaped neoplastic cells embedded in a collagenous and myxoid stroma; and a prominent vascular component with blood vessels of variable caliber spread in this myxoid stroma. This was harmonious to those reported in literature. Fletcher suggested that the immunophenotype of stromal cells was vimentin-positive, muscle-specific actin/α-smooth-muscle actin (MSA/ASMA)-variable, and desmin-negative, in AAM, whereas vimentin-positive, MSA/ASMA-negative, and desmin-negative in angimyofibroblastoma (14). In our two cases, immunophenotype presented AAM. Differential diagnosis of AAM inludes a series of benign and malignant soft tissue tumors including myxoma, myxoid liposarcoma, myxoid-type malignant fibrous histiocytoma, sarcoma botryoides, myxoid neurofibroma, myxoid leiomyoma, myxoid liposarcoma, spindle cell lipoma, vaginal polyp, malignant mesenchymoma, mixed mesodermal tumor, sclerosing hemangioma, fibroangioma and embryonal rhabdomyosarcoma (2,15). Radical surgery is often required for complete resection. In spite of complete resection, local recurrences are common. However, no deaths or distant metastases have been reported (3,11). Because prognosis and management differs greatly among myxoid neoplasms, critical evaluation of histological criteria is necessary. Immunohistochemical studies are often used to differentiate the neoplams. Fetsch et al. proposed the long-term follow-up (3). In our cases, radical surgery achieved management of AAM. In conclusion, AAM is a rare, benign neoplasm that can be mistaken both clinically and microscopically for several other conditions. It is important to diagnose this condition because the tumor is locally infiltrative and requires wide excision and follow-up. Its histology mimicking many benign and malignant tumors could lead to unnecessary radical operations as well as in adequate excisions. We demonstrated two cases of AAM with different macroscopic appearance and location. The first one was the largest labial AAM, and the second orginated from Douglas' pouch and extended into the abdomen. Address for correspondence: Ahmet Yalinkaya Dicle University Medical School Obstetrics and Gynecology Diyarbakir Turkey e-mail: [email protected]