What are the other Names for this Condition? (Also known as/Synonyms)

• Embryonal Rhabdomyosarcoma of Uterus
• ERMS of Uterine Corpus
• Uterine Embryonal RMS

What is Embryonal Rhabdomyosarcoma of Uterine Corpus? (Definition/Background Information)

• Rhabdomyosarcoma of uterine corpus is a very uncommon, high-grade malignant tumor of the uterine corpus (body of uterus). The rhabdomyosarcoma (RMS) is an infrequent, but malignant ‘skeletal muscle’ tumor of the soft tissues
• There are 3 variants of rhabdomyosarcomas including embryonal, alveolar, and pleomorphic subtypes. Embryonal Rhabdomyosarcoma (ERMS) of Uterine Corpus is a common histological subtype of rhabdomyosarcoma of uterus
• Currently, there are no specific risk factors identified for Embryonal Rhabdomyosarcoma of Uterus. However, RMS may be associated with certain genetic disorders including Beckwith-Wiedemann syndrome, Costello syndrome, and neurofibromatosis type 1, among others
• The cause of formation of Embryonal Rhabdomyosarcoma of Uterine Corpus is not well-established. It is believed to occur due to certain genetic mutations
• The signs and symptoms of Uterine Embryonal Rhabdomyosarcoma may include abnormal vaginal discharge and vaginal bleeding. The complications of the tumor may include local infiltration and metastasis to distant sites
• The treatment of Embryonal Rhabdomyosarcoma of Uterine Corpus is undertaken through surgery and/or chemotherapy. The prognosis of ERMS depends on many factors including age of the individual, the stage of the cancer, and response to therapy

Who gets Embryonal Rhabdomyosarcoma of Uterine Corpus? (Age and Sex Distribution)

• Embryonal Rhabdomyosarcoma of Uterine Corpus is a rare and invasive tumor that is mostly seen in women in the 20-45 years age range (reproductive phase)
• However, a wide age range of 20-90 years have been observed for RMS affecting the female genital tract
• No racial or ethnic preference is generally noted and the tumor is seen worldwide

What are the Risk Factors for Embryonal Rhabdomyosarcoma of Uterine Corpus? (Predisposing Factors)

Currently, no specific risk factors are noted for the development of Embryonal Rhabdomyosarcoma of Uterine Corpus. But, in general, rhabdomyosarcomas may be associated with the following factors:

• Family history of the condition has been observed, though very rarely
• Use of drugs, such as cocaine or marijuana, by the parent mother
• Carcinogens (some have been found on mice and certain types of fish)
• Beckwith-Wiedemann syndrome
• Costello syndrome
• Li-Fraumeni syndrome
• Neurofibromatosis (type) 1
• Noonan syndrome

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Embryonal Rhabdomyosarcoma of Uterine Corpus? (Etiology)

The exact cause and mechanism of formation of Embryonal Rhabdomyosarcoma of Uterine Corpus is unknown. The tumor is said to arise from embryonic connective tissues responsible for skeletal muscle development.

• A majority of the rhabdomyosarcomas are of the embryonal and pleomorphic variant
• It is suspected that either inherited genetic defects or de novo (sporadic and spontaneous) genetic mutations may be the causative factors
• Chromosomes 2, 8, and 11 have been found to be altered, indicating complex mutations with gain/loss of genetic material. Also, an absence or modification of tumor suppressor gene has been observed. These changes are said to be responsible for ERMS; but the exact process how the tumor develops, is not clearly understood

What are the Signs and Symptoms of Embryonal Rhabdomyosarcoma of Uterine Corpus?

The signs and symptoms of Embryonal Rhabdomyosarcoma of Uterine Corpus may include:

• Abnormal vaginal bleeding and/or vaginal discharge may be noted in early stage of the cancer development
• Presence of a fleshy polyp or infiltrative mass in the uterus; ERMS is particularly known to appear as a group of poorly-defined polyps
• Often tumors grow to large sizes and may cause a feeling of fullness in the abdomen; enlargement of lower abdomen
• Painful and difficulty during urination; frequent urination
• Abdominal pain (the pain is usually a pelvic pain)
• Lower back pain
• Pain during sexual intercourse

How is Embryonal Rhabdomyosarcoma of Uterine Corpus Diagnosed?

The following tools may be used towards establishing a diagnosis of Embryonal Rhabdomyosarcoma of Uterine Corpus:

• A thorough physical examination and a complete medical history evaluation is very vital to the diagnosis
• Pelvic examination: During a pelvic examination, a physician exams the uterus, vagina, ovaries, fallopian tubes, bladder, and rectum to check for any abnormal changes in these organs
• Complete blood count (CBC) with differential of white blood cells
• Liver function test (LFT)
• Blood tests called serum tumor markers that include:
  • CA-125 test
  • Human chorionic gonadotropin (hCG)
  • Alpha-fetoprotein (AFP)
  • Lactate dehydrogenase (LDH)
  • Inhibin (hormone)
  • Estrogen and testosterone levels
• Hysteroscopy: During hysteroscopy, a physician inserts a tiny telescope through the cervix into the uterus. This procedure is used to remove small amounts of the endometrium for pathological examination
• Cystoscopy: During cystoscopy, a physician inserts a narrow tube called cystoscope, to look directly into the bladder to see if cancer from endometrium has spread to the bladder. To make an individual more comfortable during this test, a local anesthetic is usually administered
• Proctoscopy: During proctoscopy, a physician inserts a narrow tube called proctoscope, to look directly into the rectum to see if cancer from endometrium has spread to the rectum. To make an individual more comfortable during this test, a general anesthetic is usually administered.
• Dilation and curettage (D&C) of the uterus: If the biopsy was inadequate in procuring enough tissue samples, or a physician is unsure whether cancer exists, a procedure called dilation and curettage may be necessary. A D&C of the uterus procedure involves opening the cervix and surgically removing the inner lining and tissue present in the uterus. To make an individual more comfortable during this procedure, a general anesthetic is usually administered
• X-ray of the abdomen and pelvic region
• Chest X-ray: Chest X-rays are used to detect if the cancer has spread to the lung
• Barium enema X-ray
• Computerized tomography (CT) scan of the abdomen and pelvic region: Also known as CAT scan, this radiological procedure creates detailed three-dimensional images of structures inside the body. CT scans are not tools of preference to detect the cancer. Although CT scans may be helpful in detecting recurrences, or if the cancer has metastasized to other organs
• MRI scan of abdomen and pelvic region
• Transvaginal ultrasound: Transvaginal ultrasound inserts an ultrasound probe into the vagina designed to take pictures of the insides of the uterus
• Vascular radiological studies of abdomen and pelvic region
• Positron emission tomography (PET scan): A PET scan is a nuclear medicine imaging technique that uses three-dimensional images to show how tissue and organs are functioning. A small amount of radioactive material is required with this test. The radioactive material may be injected into a vein, inhaled, or swallowed. It may be performed to see if the cancer has metastasized/spread to other regions
• Exploratory laparoscopy (diagnostic laparoscopy): This is a procedure wherein the abdomen is examined using a minimally invasive technique. During this procedure, a tissue biopsy and tissue for culture are performed. A minimally invasive approach helps decrease the complications and length of stay at the hospital. A diagnostic laparoscopy is also helpful in establishing the staging of the tumor
• Colonoscopy: A colonoscopy may be performed to assess the extent of tumor spread
• Whole body bone scan
• Tissue biopsy of the tumor: A biopsy refers to a medical procedure that involves the removal of cells or tissues, which are then examined by a pathologist under a microscope. After putting together the clinical findings, special studies on tissues (if needed), and the microscope findings, the pathologist arrives at a definitive diagnosis. Sometimes, the pathologist may perform special studies that may include immunohistochemical stains, histochemical stains, molecular testing, and very rarely, electron microscopic studies. Examination of the biopsy under a microscope by a pathologist is considered to be the gold standard in arriving at a conclusive diagnosis

Note: Pap smear is not a good screening tool for ERMS of Uterus.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Embryonal Rhabdomyosarcoma of Uterine Corpus?

Complications due to Embryonal Rhabdomyosarcoma of Uterus could include:

• Metastasis of the tumor to other sites in the body
• Recurrence of the tumor after surgery, when the entire tumor is not removed
• Blood loss during invasive treatment methods may be heavy
• Damage of vital nerves, blood vessels, and surrounding structures during surgery
• Perforation in the uterus, which may occur during a diagnostic D&C or endometrial tissue biopsy procedure
• Side effects from chemotherapy (toxicity), radiation therapy (radiation fibrosis)
• Sexual dysfunction can take place as a side effect of surgery, chemotherapy, or radiation therapy

How is Embryonal Rhabdomyosarcoma of Uterine Corpus Treated?

Once a diagnosis of cancer of the uterus has been made, the extent to which the tumor has spread is assessed. This is called staging.

Following is the staging protocol for uterine cancer, according to the American Joint Committee on Cancer (AJCC), updated July 2016:

Stage I uterine cancer: The cancer is found in the uterus only. Stage I is divided into stages IA and IB, based on how far the cancer has spread.

• Stage IA: The cancer is in the endometrium only or less than halfway through the myometrium (muscle layer of the uterus).
• Stage IB: The cancer has spread halfway or more into the myometrium.

Stage II uterine cancer: The cancer has spread into connective tissue of the cervix, but has not spread outside the uterus.

Stage III uterine cancer: The cancer has spread beyond the uterus and cervix, but has not spread beyond the pelvis. Stage III is divided into stages IIIA, IIIB, and IIIC, based on how far the cancer has spread within the pelvis.

• Stage IIIA: The cancer has spread to the outer layer of the uterus and/or to the fallopian tubes, ovaries, and ligaments of the uterus.
• Stage IIIB: The cancer has spread to the vagina and/or to the parametrium (connective tissue and fat around the uterus).
• Stage IIIC: The cancer has spread to lymph nodes in the pelvis and/or around the aorta (largest artery in the body, which carries blood away from the heart).

Stage IV uterine cancer: The cancer has spread beyond the pelvis. Stage IV is divided into stages IVA and IVB, based on how far the cancer has spread.

• Stage IVA: The cancer has spread to the bladder and/or bowel wall.
• Stage IVB: The cancer has spread to other parts of the body beyond the pelvis, including the abdomen and/or lymph nodes in the groin.

(Source: Stages of Uterine Cancer, July 2016, provided by the National Cancer Institute at the National Institutes of Health; U.S. Department of Health and Human Services)

The treatment of Embryonal Rhabdomyosarcoma of Uterine Corpus may be undertaken as:

• Any combination of chemotherapy, radiation therapy, and invasive surgical procedures may be used to treat RMS of Uterine Corpus
• Surgery may include the following procedures:
  • Hysterectomy: In this procedure, the uterus and cervix are removed. This is done by making an incision on the abdomen (termed abdominal hysterectomy), or through the vagina (termed vaginal hysterectomy), or by using a laparoscope (termed laparoscopic hysterectomy). Surgery is performed under general or epidural anesthesia, though the ability to have children is lost. Complications, such as bleeding, infection, or damage to the urinary tract, or the intestinal system may occur in rare cases
  • Radical hysterectomy: The uterus, cervix, the upper part of the vagina and tissues, next to the uterus are removed. Additionally, some pelvic lymph nodes may also be surgically taken out. The surgery is performed under anesthesia and may be carried out, via an incision made on the abdomen or by using laparoscopy. With this invasive procedure, the ability to have children is lost. Rarely, complications such as bleeding, infection, or damage to the urinary tract or the intestinal system, may occur. Removal of lymph nodes may lead to swelling of legs (lymphedema)
  • Pelvic exenteration: The uterus, tissues surrounding the uterus, cervix, pelvic lymph nodes, and the upper part of the vagina, are removed. In addition, depending on the tumor spread, the remainder of the vagina, the bladder, rectum, and a part of the colon, may also be removed. Recovery from this surgery takes a long period
• Arterial embolization may be used to provide temporary relief from the symptoms, and reduce blood loss during a surgical procedure
• Chemotherapy:
  • Medications are used to kill the tumor cells, which may be given as oral pills or injected into veins
  • A combination of chemotherapy medications may be used
• Radiation therapy:
  • This procedure uses high-energy beams to kill the cancer cells
  • These beams may be delivered from outside the body (external beam radiation therapy) or the radioactive material maybe placed inside the vagina or the uterus (internal radiation therapy or brachytherapy)
• Post-operative care is important: One must maintain minimum activity levels, until the surgical wound heals
• Follow-up care with regular screening and check-ups are important and encouraged

How can Embryonal Rhabdomyosarcoma of Uterine Corpus be Prevented?

• Current medical research has not established a way of preventing the formation of Embryonal Rhabdomyosarcoma of Uterine Corpus
• Genetic counseling and testing: If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Due to its high metastasizing potential and recurrence rate, regular medical screening at periodic intervals with blood tests, scans, and physical examinations, are mandatory for those who have already been treated for this tumor

What is the Prognosis of Embryonal Rhabdomyosarcoma of Uterine Corpus? (Outcomes/Resolutions)

• The prognosis of Embryonal Rhabdomyosarcoma of Uterine Corpus depends on a combination of factors that include:
  • The size of the tumor and the extent of its invasion: Individuals with small-sized tumors fare better than those with large-sized tumors
  • Stage of cancer: With lower-stage tumors, when the tumor is confined to site of origin, the prognosis is usually excellent with appropriate therapy. In higher-stage tumors, such as tumors with metastasis, the prognosis is poor. The stage of the cancer is an independent prognostic factor
  • Histological subtype of the tumor
  • Cell growth rate of the cancer
  • Overall health of the individual: Individuals with overall excellent health have better prognosis compared with those with poor health
  • Age of the individual: Older individuals generally have poorer prognosis than younger individuals. In general, if the age of the patient is over 20 years, it is associated with a poor prognosis. This is also an independent prognostic factor
  • Individuals with bulky disease have a poorer prognosis
  • Involvement of the regional lymph nodes, which can adversely affect the prognosis
  • Involvement of vital organs may complicate the condition
  • The surgical respectability of the tumor (meaning, if the tumor can be removed completely)
  • Whether the tumor is occurring for the first time, or is a recurrent tumor. Recurring tumors have worse prognosis compared to tumors that do not recur
  • Response to treatment: Tumors that respond to treatment have better prognosis compared to tumors that do not respond to treatment
  • Progression of the condition makes the outcome worse
• The embryonal variant of RMS has a better prognosis than the alveolar and pleomorphic variants. However, the prognosis mainly depends on the stage of the tumor
• An early diagnosis and prompt treatment of the tumor generally yields better outcomes than a late diagnosis and delayed treatment
• The combination chemotherapy drugs used, may have some severe side effects (like cardio-toxicity). This chiefly impacts the elderly adults, or those who are already affected by other medical conditions. Individuals, who tolerate chemotherapy sessions better, generally have better outcomes

Additional and Relevant Useful Information for Embryonal Rhabdomyosarcoma of Uterine Corpus:

• Removal of the uterus will cause the regular menstrual bleeding to stop. This also means that a woman may not have children after uterus removal; though, sexual intercourse is still possible
• Amongst pediatric soft tissue sarcomas (affecting children less than 15 years), rhabdomyosarcomas form the largest category of malignant tumors