Endometrial stromal sarcoma (ESS) is a malignant variant of endometrial stromal tumors (ESTs) and encompasses approximately 2-5% of all neoplasms originating in the endometrium, although it is rarely encountered clinical practice [1]. Some authors established an incidence rate of 1-2 per 100,000 women [1], while others claim it to be as low as 1-2 per 1 million women in 1 year [2]. Based on the degree of proliferation, ESSs are either low-grade or high-grade tumors, but all forms penetrate the myometrium of the uterus, which is the main distinguishing feature from benign forms of ESTs (endometrial stromal nodules) [1]. However, some authors claim that all ESSs should be considered as low-grade sarcomas, and the term undifferentiated endometrial sarcomas (UES) should be used to describe high-grade tumors with an incompletely disclosed phenotype instead [2] [3]. They are primarily diagnosed in women between 40-60 years of age, with low-grade tumors being more commonly identified in younger women, whereas postmenopausal females are the primary patient population of high-grade ESS [1] [2] [3] [4] [5]. The clinical presentation is comprised of nonspecific symptoms such as abdominal pain, vaginal bleeding, and progressive metrorrhagia in premenopausal women [3] [4]. A palpable abdominal mass may be detected in up to a quarter of individuals [4].

• Fatigue

  A 59-year-old female presented with new abdominal onset pain, fatigue, and nausea. She had a computed tomography that showed a pelvic mass, an enlarged right internal iliac lymph node, an atypical liver hemangioma, and a severe left hydronephrosis. [ncbi.nlm.nih.gov]

  We ask about general symptoms (anxious mood, depressed mood, fatigue, pain, and stress) regardless of condition. Last updated: January 31, 2019 [patientslikeme.com]

  A 75-year-old woman status post total abdominal hysterectomy for “multiple leiomyomas” presented with fatigue, dyspnea, and anemia, and underwent colonoscopy where numerous “malignant” appearing polyps were noted. [academic.oup.com]

  GIST Symptoms of Gastrointestinal Stromal Tumor (GIST) Gastrointestinal stromal tumors may cause the following symptoms: Abdominal discomfort or pain Blood in stools Vomiting Feeling full after eating only a small amount Loss of appetite or weight loss Fatigue [brighamandwomens.org]

• Soft Tissue Mass

  A 43-year-old, nulligravid, Caucasian woman presented for an annual gynecologic examination and was found to have an asymptomatic 5 x 5-mm, rubbery, soft tissue mass at the 5 o'clock position of the vaginal introitus. [ncbi.nlm.nih.gov]

  tissue mass at the 5 o clock position of the vaginal introitus. [reproductivemedicine.com]

  Chest CT revealed a tightly packed elongated endobronchial soft tissue mass completely obstructing the right intermediate bronchus and a solitary round nodule, 3.6 cm 2.6 cm in size, in the medial basal segment of right lower lobe (figure 1). [thorax.bmj.com]

• Accelerated Growth

  Recurrence is usually confined to the pelvic space but sometimes accelerated growth and extension into the upper abdomen can be found. [ncbi.nlm.nih.gov]

• Wheelchair Bound

  While surviving at 24 months from recurrent disease, the second became paraplegic with double incontinence and was wheelchair bound. [ncbi.nlm.nih.gov]

• Orthopnea

  We show the case report of a woman with endometrial stromal sarcoma who developed a right heart failure, lower extremity edema, dyspnea and orthopnea after the initial step of comprehensive surgery and radiotherapy. [oatext.com]

• Abdominal Pain

  Abdominal pain, vaginal bleeding, and menorrhagia are main symptoms, whereas a palpable abdominal mass may be detected in a number of patients. Clinical suspicion towards this tumor must be raised early. [symptoma.com]

  Other associated symptoms were the abdominal enlargement and the presence of the pelviabdominal mass generated by the tumor, low to medium abdominal pain or polakiuria. [ncbi.nlm.nih.gov]

• Peritoneal Disease

  All 3 were associated with an aggressive clinical course, including multisite bony metastases in 1 patient, progressive peritoneal disease after chemotherapy in another, and metastases to the lung and skin in the last patient. [ncbi.nlm.nih.gov]

• Adnexal Mass

  A preoperative diagnosis of a submucous leiomyoma with an adnexal mass was made. At laparotomy, the leiomyoma was found to be wedged between the cervix and the vagina, and was removed vaginally. [casereports.bmj.com]

  View Article Google Scholar Mathevet P, Nessah K, Dargent D, Mellier G: Laparoscopic management of adnexal masses in pregnancy: a case series. Eur J Obstet Gynecol Reprod Biol. 2003, 108: 217-222. [jmedicalcasereports.com]

  Definitive diagnosis of any uterine sarcoma based on sonography alone is not possible [5] because these kinds of tumors may have nonspecific findings such as polypoid endometrial masses, endomyometrial thickening, and adnexal masses. [ajronline.org]

  Pelvic examination displayed a nontender mass from the lateral wall of the uterus without pain, and no adnexal mass was palpatable. [alliedacademies.org]

  No adnexal masses were palpated. Primary diagnosis was determined as submucous myoma and a myomectomy was performed by hysteroscopy. [spandidos-publications.com]

Despite the rare appearance of endometrial stromal sarcoma, the physician must perform a comprehensive clinical assessment in women who report with undisclosed abdominal pain and vaginal bleeding. A detailed patient history should be obtained first, during which the duration of symptoms and their severity, as well as the menopausal status, need to be assessed. Because a palpable mass was observed in a small, but a significant number of cases, abdominal inspection and palpation must not be overlooked during the physical examination. Imaging studies must be employed as soon as possible. Ultrasonography, despite its benefits in terms of convenience and time consumption, is not a reliable tool for discriminating between uterine lesions, and it is not uncommon for endometrial stromal sarcomas to be misdiagnosed as leiomyomas [1] [2] [3] [4]. For this reason, magnetic resonance imaging (MRI) is the recommended study, as it can confirm the presence of a lesion invading the myometrium and enlargement of the uterus [2]. A definite diagnosis is made after obtaining a viable sample for a histopathological examination with immunohistochemistry and uterine curettage is the crucial procedure that allows proper sampling [1] [2]. Expression of CD10 on immunohistochemistry is a highly specific sign for endometrial stromal sarcomas [2] [6] [7].

• Cavitary Lesion

  A 57-year-old woman, who had undergone hysterectomy for uterine myoma 11 years earlier presented with cystic, nodular and cavitary lesions simultaneously visible on computed tomography images of the chest. [ncbi.nlm.nih.gov]

• Multiple Pulmonary Nodules

  We are reporting a case of a 47-year-old female with no significant medical history who presented with multiple pulmonary nodules. Fine needle aspiration (FNA) specimen revealed spindle cell neoplasm consistent with the diagnosis of LGESS. [ncbi.nlm.nih.gov]

• Ovarian Mass

  Intraoperative findings included a solitary solid and multicystic right ovarian mass without evidence of any extraovarian disease. [ncbi.nlm.nih.gov]

  We present the case of a 48-year-old woman who underwent an exploratory laparotomy for pelvic pain and a suspected right ovarian mass based on imaging studies. [academic.oup.com]

  Sonographic examination suggested an appendicular plastron and was interpreted as an ovarian mass. Subsequently, a laparoscopy was performed in a district hospital. [jmedicalcasereports.com]

• Foam Cell

  Foam cells were present in 6 tumors. The tumors showed minimal cytologic atypia. The mitotic index ranged from [ncbi.nlm.nih.gov]

  May have foam cells or hyalinization in the stroma. [en.wikipedia.org]

  Other morphologic patterns seen that are not unique to extrauterine sites include prominent hyaline plaques (Figure 2, B), foam cell change (Figure 2, C), florid glandular differentiation (Figure 2, D), sex cord elements (Figure 2, E), and prominent myxoid [archivesofpathology.org]

1. Puliyath G, Nair VR, Singh S. Endometrial stromal sarcoma. Indian J Med Paediatr Oncol. 2010;31(1):21-23.
2. Puliyath G, Nair MK. Endometrial stromal sarcoma: A review of the literature. Indian J Med Paediatr Oncol. 2012;33(1):1-6.
3. Ashraf-Ganjoei T, Behtash N, Shariat M, Mosavi A. Low grade Endometrial Stromal Sarcoma of uterine corpus, a clinico-pathological and survey study in 14 cases. World J Surg Oncol. 2006;4:50.
4. Kim DY, Lim KT, Kwon YS. Endometrial Stromal Sarcomas: A clinico-pathological analysis of 27 patients. Pak J Med Sci. 2013;29(1):72-76.
5. Baker P, Oliva E. Endometrial stromal tumours of the uterus: a practical approach using conventional morphology and ancillary techniques. J Clin Pathol. 2007;60(3):235-243.
6. Sumathi VP, McCluggage WG. CD10 is useful in demonstrating endometrial stroma at ectopic sites and in confirming a diagnosis of endometriosis. J Clin Pathol. 2002;55:391–32.
7. Chu PG, Arber DA, Weiss LM, Chang KL. Utility of CD10 in distinguishing between endometrial stromal sarcoma and uterine smooth muscle tumors: An immunohistochemical comparison of 34 cases. Mod Pathol. 2001;14:465–471.