Müllerian Adenosarcoma Arising in a Subserosal Adenomyoma

Abstract

Müllerian adenosarcomas most commonly arise in the uterine corpus from the eutopic endometrium. Occasionally, they arise in the cervix, vagina, broad and round ligaments, and ovaries and rarely in extragenital sites, usually in association with endometriosis. The authors report a rare case of extraendometrial, intramural adenosarcoma of low grade arising from a subserosal adenomyoma in a 46-year-old woman who presented with vaginal bleeding. No evidence of eutopic endometrial origin was identified; the adenosarcoma showed only limited myometrial invasion and no serosal involvement. Because of its subserosal location, the tumor would be overstaged as IC (deeply myoinvasive) in the new FIGO staging system. Stage IC tumors would normally be considered for adjuvant treatment, which would be inappropriate in this case. To avoid overstaging and inappropriate treatment, it is important to recognize that adenosarcoma can, rarely, arise in adenomyomas (or adenomyosis).

A Rare Case of Intramural Müllerian Adenosarcoma Arising from Adenomyosis of the Uterus

“…In fact, only a few prior cases of primary adenosarcoma arising from adenomyosis have been reported in the English literature [2,5,8,10]. The present report describes the clinical and pathologic findings of a rare case of extraendometrial, intramural adenosarcoma arising from adenomyosis without eutopic endometrial involvement in a 40-year-old woman and briefly reviews the literature describing the clinical and pathologic characteristics of adenosarcoma arising from adenomyosis.…”

“…The term Müllerian adenosarcoma was first used in 1974 to describe an unusual variant of Müllerian mixed tumor of the uterus, characterized by a mixture of benign or occasionally mildly atypical glandular components and malignant, usually low-grade, stromal components [2]. The morphologic features of these neoplasms distinguish them from other biphasic (epithelial and mesenchymal) tumors, both benign and malignant [1].…”

“…Müllerian adenosarcoma is generally of low malignant potential, except when accompanied by sarcomatous overgrowth and myoinvasion [1]. Patients with Müllerian adenosarcoma lacking these two histopathologic features have an excellent prognosis [1]; these tumors may recur locally but only rarely metastasize [2]. …”

“…Müllerian adenosarcomas generally arise from the eutopic endometrium in the uterine corpus and grow as polypoid masses in post-menopausal women who present with abnormal vaginal bleeding [2,3]. These neoplasms, however, may also arise in ectopic foci of endometriosis, such as the uterine cervix, vagina, broad and round ligaments, and ovaries or even at extragenital sites in rare cases [4,5].…”

“…For example, among 41 previously reported Müllerian adenosarcomas, 29 (71%) were extrauterine [6], with the sites including the ovaries, cervix, peritoneum, pelvis, gastrointestinal tract, bladder, perirectal tissue, rectovaginal septum, pouch of Douglas, and liver [7]. Some studies have reported that adenosarcomas arising in extrauterine and extragenital area may be associated with more aggressive clinical behavior, probably due to an increasing tendency for peritoneal spread [2]. …”