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

• Arias-Stella Effect of Uterine Corpus
• Arias-Stella Phenomenon of Uterus
• Uterine Arias-Stella Reaction

What is Arias-Stella Reaction of Uterine Corpus? (Definition/Background Information)

• Arias-Stella Reaction of Uterine Corpus is a benign tumor-like condition caused due to a change in the endometrium of the uterus. The condition is a normal physiological process of the body, caused due to hormonal response
• It is mostly observed in pregnant women, or sometimes, in women with gestational trophoblastic disease (a group of rare, pregnancy-related tumors)
• It is an incidental finding during a microscopic examination by the pathologist. Arias-Stella Reaction of Uterus is similar to Arias-Stella reaction of the cervix
• There are no clearly established risk factors for Uterine Arias-Stella Reaction and the cause of tumor formation is unknown. However, it may be influenced by hormonal changes
• No significant signs and symptoms or complications are typically noted. However, it is important to undertake a differential diagnosis to rule out any carcinomas or precancers
• There is no treatment necessary for the condition, since it is asymptomatic and benign. In general, the prognosis of Arias-Stella Reaction of Uterine Corpus is excellent
• Nevertheless, if underlying gestational trophoblastic disease is observed, then there may be significant signs and symptoms, complications, the necessity for extensive treatment, and the prognosis may depend upon the severity of the disease and overall health of the individual

Who gets Arias-Stella Reaction of Uterine Corpus? (Age and Sex Distribution)

• Arias-Stella Reaction of Uterine Corpus is mostly observed in pregnant women, and occasionally in women with gestational trophoblastic disease/tumor
• There is no known ethnic or racial preference

What are the Risk Factors for Arias-Stella Reaction of Uterine Corpus? (Predisposing Factors)

• No definitive risk factors have been identified for Arias-Stella Reaction of Uterine Corpus. However, a majority of the cases are observed during pregnancy (and occasionally in women with ectopic pregnancy)
• Women undergoing hormone therapy, such as with progestins (high-dose) and gonadotropins, are also at risk
• Some cases are observed in women having gestational trophoblastic disease (such as choriocarcinoma, partial mole, complete mole, etc.) and the related risk factors include:
  • Age: Women under the age of 20 and over the age of 35 years
  • Previous history of gestational trophoblastic disease
  • Being from Asia (Asian ethnicity)
  • Women with blood group type A
  • Women who have had earlier miscarriages and difficulties getting pregnant. Also, the risk is higher for women who uses birth-control pills
  • Women belonging to lower income groups or with lower education levels seem to also have a higher risk
  • Low levels of beta-carotene in the diet is a risk factor for gestational trophoblastic disease

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 Arias-Stella Reaction of Uterine Corpus? (Etiology)

• Currently, the exact cause and mechanism of formation of Arias-Stella Reaction of Uterine Corpus is unknown
• However, the condition may be due to hormonal changes in women, since it is mostly seen during pregnancy or in association with hormonal treatment
• Gestational trophoblastic diseases/tumors develop from various abnormalities that occur during sperm-egg fertilization, or due to hydatidiform moles (abnormal formations of mass during onset of pregnancy), or other unknown causes

What are the Signs and Symptoms of Arias-Stella Reaction of Uterine Corpus?

• In a majority of cases, against a background of normal pregnancy, Arias-Stella Reaction of Uterine Corpus is asymptomatic and presents no significant signs and symptoms
• The condition may develop within the endometrial glands
• Arias-Stella reaction or Arias-Stella phenomenon may also be observed in the uterine cervix

In some cases, Arias-Stella reaction is seen with gestational trophoblastic disease. In such cases, the signs and symptoms of underlying gestational trophoblastic tumors may include:

• Vaginal bleeding
• Enlarged uterus
• Pelvic pain and discomfort
• Severe nausea and vomiting

How is Arias-Stella Reaction of Uterine Corpus Diagnosed?

A diagnosis of Arias-Stella Reaction of Uterine Corpus may involve the following steps:

• Evaluation of the individual’s medical history
• A thorough physical (pelvic) examination

The context under which Arias-Stella reaction is diagnosed is important. If Arias-Stella reaction occurs in the context of a normal pregnancy, then no further diagnostic work-up may be necessary; however, if it occurs due to underlying gestational trophoblastic disease, then the following diagnostic methods may be considered:

• Ultrasound scan of the abdomen
• CT or CAT scan with contrast of the abdomen and pelvis may show a well-defined mass. This radiological procedure creates detailed 3-dimensional images of structures inside the body
• MRI scans of the abdomen and pelvis: Magnetic resonance imaging (MRI) uses a magnetic field to create high-quality pictures of certain parts of the body, such as tissues, muscles, nerves, and bones. These high-quality pictures may reveal the presence of the tumor
• Blood test for checking beta-hCG (human chorionic gonadotropin) levels
• Pap smear: In some women, a screening Pap smear may show atypical cells due to Arias-Stella Reaction of Uterine Corpus. This often requires a follow-up biopsy
• Hysteroscopy: This procedure involves placing a probe through the cervix to examine the cavity of the uterus. This exam is helpful in detecting submucosal tumors
• Hysterosalpingography: It is usually performed in individuals with infertility. In this procedure, the structure of the uterus and fallopian tubes are studied by using a dye and X-ray images
• Colposcopy: The cervix is examined with an instrument, called a colposcope. This helps the physician get a magnified view of the cervix

Note:

• The cells of Arias-Stella reaction may appear atypical when examined under a microscope. Hence, a careful microscopic examination should be performed, to rule out the possibility of clear cell adenocarcinoma of cervix and endocervical adenocarcinoma in situ
• Arias-Stella reaction is normally an incidental finding, while the women is being examined for other medical conditions

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 Arias-Stella Reaction of Uterine Corpus?

• No significant complications of Arias-Stella Reaction of Uterine Corpus are noted if associated with pregnancy, because in the context of normal pregnancy, Arias-Stella reaction is a benign and harmless condition
• Also, study reports indicate that no malignant transformations have been observed in the context of normal pregnancy

If Arias-Stella reaction occurs due to an underlying gestational trophoblastic disease, then complications related to the disease may be observed, such as:

• Vaginal bleeding that may lead to anemia
• Spread of choriocarcinoma to other body parts

How is Arias-Stella Reaction of Uterine Corpus Treated?

• Generally, no treatment measures are necessary for Arias-Stella Reaction of Uterine Corpus, if associated with pregnancy
• Follow-up care with regular screening and check-ups are important

However, if Arias-Stella Reaction of Uterine Corpus is due to an underlying gestational trophoblastic disease, then appropriate treatment for the disease should be instituted. The treatment of gestational trophoblastic tumors depends upon the following factors:

• Location of the tumor
• Extent of the condition
• Type of gestational trophoblastic tumor
• Level of human chorionic gonadotropin (hCG) hormone
• Duration of the condition
• Extent and sites of metastases

The treatment methods may include:

• Surgery: Hydatidiform moles are generally removed by dilatation and suction curettage (D & C). Sometimes, the surgery may involve the complete removal of the uterus (hysterectomy)
• Chemotherapy and radiation therapy: If the tumors have spread beyond the uterus
• Drugs, such as methotrexate or actinomycin-D, are recommended for women who have had the hydatidiform moles removed, though they still persist
• Methotrexate, cyclophosphamide, etoposide, vincristine, and actinomycin-D are drugs used in the treatment of choriocarcinomas
• Sometimes a combination of the above medications, chemotherapy, and surgery may be employed to obtain effective results

How can Arias-Stella Reaction of Uterine Corpus be Prevented?

Arias-Stella Reaction of Uterine Corpus during pregnancy is a normal physiological process and no prevention is necessary.

• During pregnancy, regular prenatal checkups are necessary to monitor the health of the expectant mother and baby in the womb
• Current medical research has not established a method of preventing Arias-Stella Reaction of Uterus that occurs in a background of gestational trophoblastic disease
• Women with a history of gestational trophoblastic disease should consult their healthcare provider before becoming pregnant
• Women with a history of one or more molar pregnancies should consult their healthcare provider to understand the risk of future molar pregnancies

What is the Prognosis of Arias-Stella Reaction of Uterine Corpus? (Outcomes/Resolutions)

• The prognosis of Arias-Stella Reaction of Uterine Corpus is excellent when associated with pregnancy, since it is a benign condition
• No unfavorable outcomes or complications are noted during pregnancy, due to the presence of Arias-Stella reaction involving the uterus
• If Arias-Stella Reaction of Uterine Corpus is associated with gestational trophoblastic disease/tumors, then the prognosis can significantly vary. The overall prognosis of the individual depends on the type of underlying gestational trophoblastic disease
• In general, all forms of gestational trophoblastic tumors can be effectively treated to result in a complete cure in a majority of cases

Additional and Relevant Useful Information for Arias-Stella Reaction of Uterine Corpus:

• Gestational trophoblastic tumors generally affect women who are in their childbearing age. It occurs very rarely in postmenopausal women

The following link is a useful resource for gestational trophoblastic tumors:

http://www.dovemed.com/diseases-conditions/gestational-trophoblastic-tumors/