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

• Malignant Rhabdomyoma of Vulva
• RMS of Vulva
• Vulvar Rhabdomyosarcoma

What is Rhabdomyosarcoma of Vulva? (Definition/Background Information)

• Rhabdomyosarcoma of Vulva is a very uncommon, high-grade malignant tumor of the vulva. The rhabdomyosarcoma (RMS) is an infrequent, but malignant ‘skeletal muscle’ tumor of the soft tissues. RMS tumors are poorly-defined, fleshy, expanding masses that form deep within the body tissues, or below the skin surface
• There are 3 types of rhabdomyosarcomas including the embryonal, alveolar, and pleomorphic subtypes. The most common type that is present in the vulva is embryonal rhabdomyosarcoma
• Currently, there are no specific risk factors identified for Rhabdomyosarcoma of Vulva. 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 Rhabdomyosarcoma of Vulva is not well-established. It is believed to occur due to certain genetic mutations. The signs and symptoms of Vulvar Rhabdomyosarcoma include the presence of a fleshy mass in the vulva (area around the external opening of vagina)
• The treatment of Rhabdomyosarcoma of Vulva is undertaken through surgery and/or chemotherapy. The prognosis of Vulvar RMS depends on many factors including age of the individual, the stage of the cancer, and response to therapy

Who gets Rhabdomyosarcoma of Vulva? (Age and Sex Distribution)

• Rhabdomyosarcoma of Vulva is a rare and invasive tumor; RMS is generally more common in the head and neck region, followed by the female genital tract (or genitourinary system)
• Primary RMS tumors affecting the vulva are very rare; the vagina is the most common site for this tumor
  • The embryonal variant of Vulvar Rhabdomyosarcoma is seen in girls below age 8-10 years
  • The alveolar variant of Vulvar Rhabdomyosarcoma is generally seen in older girls and young women
• 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

What are the Risk Factors for Rhabdomyosarcoma of Vulva? (Predisposing Factors)

Currently, no specific risk factors are noted for the development of Rhabdomyosarcoma of Vulva. 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 Rhabdomyosarcoma of Vulva? (Etiology)

The exact cause and mechanism of formation of Rhabdomyosarcoma of Vulva is unknown.

• A majority of the Vulvar Rhabdomyosarcomas are of the embryonal variant, which are thought to arise from embryonic connective tissues responsible for skeletal muscle development
• Other variants, such as the alveolar and pleomorphic variants, are very uncommon
• It is suspected that either inherited genetic defects or de novo (sporadic and spontaneous) genetic mutations may be the causative factors

Vulvar Rhabdomyosarcoma is not a sexually-transmitted disease/condition.

What are the Signs and Symptoms of Rhabdomyosarcoma of Vulva?

The signs and symptoms of Rhabdomyosarcoma of Vulva may include:

• Presence of fleshy polypoid mass or infiltrative mass on the vulva
• The tumor may appear fluid-filled (edematous)
• In some cases, the skin over the mass may ulcerate and result in bleeding
• Pain during sex
• Frequent urination due to compression/pressure of large tumors
• If the urinary bladder is involved, then it may obstruct the bladder and lead to retention of urine
• Pain in the pelvic or abdominal region
• Lower back pain

How is Rhabdomyosarcoma of Vulva Diagnosed?

The following tools may be used towards establishing a diagnosis of Rhabdomyosarcoma of Vulva:

• Evaluation of the individual’s medical history and a thorough physical (pelvic) examination
• Transvaginal ultrasound of the uterus can provide an image of the vagina and surrounding pelvic organs
• MRI scans can be used to observe if a vulvar tumor has the characteristics of cancer, along with visualizing the cancer spread (if it has spread to other areas)
• CT scans are rarely used in diagnosing vulvar cancer, but can be used to determine if metastasis has occurred
• Plain radiographs of the chest can provide evidence if the tumor has spread to the lungs
• Colposcopy:
  • The cervix (including the vagina and vulva) is examined with an instrument, called a colposcope. This helps the physician get a magnified view of the cervix
  • In order for this procedure to be performed, the individual has to lie on a table, as for a pelvic exam. An instrument, called the speculum, is placed in the vagina to keep the opening apart, in order to help the physician visualize the cervix. The colposcope is then used to get a magnified view of the inside
• A vulvar biopsy may be necessary to determine, if the tumor present is a rhabdomyosarcoma, or a different soft tissue sarcoma. In the tissue biopsy procedure, the physician removes a sample of the tissue and sends it to the laboratory for a histopathological examination. The pathologist examines the biopsy under a microscope and arrives at a definitive diagnosis after a thorough evaluation of the clinical and microscopic findings, as well as by correlating the results of special studies on the tissues (if required)

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 Rhabdomyosarcoma of Vulva?

Complications due to Rhabdomyosarcoma of Vulva 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
• Side effects of chemotherapy (such as toxicity) and radiation
• Sexual dysfunction can take place as a side effect of surgery, chemotherapy, or radiation therapy, later in life
• Recurrence of the cancer following incomplete surgical removal is known to be frequent

How is Rhabdomyosarcoma of Vulva Treated?

Once a diagnosis of vulvar cancer has been made, the extent to which the tumor has spread is assessed, known as staging. The staging for vulvar cancer is based upon the FIGO (International Federation of Gynecology and Obstetrics) and the AJCC (American Joint Committee on Cancer) TNM staging systems.

The TNM classification for vulvar cancer is given below:

Tumor extent (T):

• Tis: The cancer is not growing into the underlying tissues. This stage, also known as carcinoma in situ, is not included in the FIGO system
• T1: The cancer is growing only in the vulva or perineum
  • T1a: The cancer has grown no more than 1 mm into underlying tissue (stroma) and is 2 cm or smaller in size (about 0.8 inches)
  • T1b: The cancer is either more than 2 cm or it has grown more than 1 mm into underlying tissue (stroma)
• T2: The tumor can be any size. The cancer is growing into the anus or the lower third of the vagina or urethra (the tube that drains urine from the bladder). This is called stage 2/3 in the FIGO system
• T3: The tumor can be any size. The cancer is growing into the upper urethra, bladder or rectum or into the pubic bone. This is called stage 4 in the FIGO system

Lymph node spread of cancer (N):

• N0: No lymph node spread
• N1: The cancer has spread to 1 or 2 lymph nodes in the groin with the following features:
  • N1a: The cancer has spread to 1 or 2 lymph nodes and the areas of cancer spread are both less than 5 mm (about 1/5th of an inch) in size
  • N1b: The cancer has spread to one lymph node and the area of cancer spread is 5 mm or greater
• N2: The cancer has spread to groin lymph nodes with the following features:
  • N2a: The cancer has spread to 3 or more lymph nodes, but each area of spread is less than 5 mm
  • N2b: The cancer has spread to 2 or more lymph nodes with each area of spread 5 mm or greater
  • N2c: The cancer has spread to lymph nodes and has started growing through the outer covering of at least one of the lymph nodes (called extracapsular spread)
• N3: The cancer has spread to the lymph nodes causing open sores (ulceration) or causing the lymph node to be stuck (fixed) to the tissue below it

Distant spread of cancer (M)

• M0: No distant spread
• M1: The cancer has spread to distant sites (includes spread to pelvic lymph nodes)

Stage grouping: Once the T, N, and M categories have been assigned, this information is combined to assign an overall stage in a process called stage grouping. The stages identify tumors that have a similar outlook and are treated in a similar way.

Stage 0 (Tis, N0, M0):

• This is a very early cancer found on the surface of the skin of the vulva only. It is also known as carcinoma in situ and as Bowen disease
• This stage is not included in the FIGO system

Stage I (T1, N0, M0):

• The cancer is in the vulva or the perineum (the space between the rectum and the vagina) or both
• The tumor has not spread to lymph nodes or distant sites
• Stage IA (T1a, N0, M0):
  • These are stage I cancers with tumors that are 2 cm or less that have grown into the underlying tissue no deeper than 1 mm (about 1/25 inch)
• Stage IB (T1b, N0, M0):
  • These are stage I cancers that have invaded deeper than 1 mm and/or are larger than 2 cm

Stage II (T2, N0, M0):

• The cancer has grown outside the vulva or perineum to the anus or lower third of the vagina or urethra (T2)
• It has not spread to lymph nodes (N0) or distant sites (M0)
• In FIGO, this grouping is T2/T3, N0, M0, but it is still stage II

Stage III is subdivided into 3 stages that are termed as Stage IIIA, Stage IIIB, and Stage IIIC.

Stage IIIA (T1 or T2, N1a or N1b, M0):

• Cancer is in the vulva or perineum or both (T1) and may be growing into the anus, lower vagina, or lower urethra (T2)
• Either it has spread to a single nearby lymph node with the area of cancer spread 5 mm or greater in size (N1a);
• OR it has spread to 1 or 2 nearby lymph nodes with both areas of cancer spread less than 5 mm in size (N1b). It has not spread to distant sites (M0)

In FIGO, this stage is also IIIA, but it is split into IIIAi and IIIAii.

• Stage IIIAi (T1 or T2, N1a, M0):
  • The cancer is in the vulva or perineum and may be any size and growing into the anus, lower vagina, or lower urethra (T1 or T2)
  • It has spread to a single lymph node with the area of spread 5 mm or greater in size (N1a)
  • It has not spread to distant sites (M0)
• Stage IIIAii (T1 or T2, N1b, M0):
  • The cancer is in the vulva or perineum and may be any size and growing into the anus, lower vagina, or lower urethra (T1 or T2)
  • It has spread to 1 or 2 lymph nodes with the areas of cancer spread less than 5 mm in size (N1b)
  • It has not spread to distant sites (M0)

Stage IIIB (T1 or T2, N2a or N2b, M0):

• Cancer is in the vulva or perineum or both (T1) and may be growing into the anus, vagina, or lower urethra (T2)
• Either, the cancer has spread to 3 or more nearby lymph nodes, with all areas of cancer spread less than 5 mm in size (N2a)
• OR the cancer has spread to 2 or more lymph nodes with each area of spread 5 mm or greater in size (N2b)
• The cancer has not spread to distant sites (M0)

In FIGO, this stage is also IIIB, but it is split into IIIBi and IIIBii.

• Stage IIIBi (T1 or T2, N2a, M0):
  • The cancer is in the vulva or perineum and may be any size and growing into the anus, lower vagina, or lower urethra (T1 or T2)
  • The cancer has spread to 3 or more nearby lymph nodes, with all areas of cancer spread less than 5 mm in size (N2a)
  • It has not spread to distant sites (M0)
• Stage IIIBii (T1 or T2, N2b, M0):
  • The cancer is in the vulva or perineum and may be any size and growing into the anus, lower vagina, or lower urethra (T1 or T2)
  • The cancer has spread to 2 or more lymph nodes with each area of spread 5 mm or greater in size (N2b)
  • It has not spread to distant sites (M0)

Stage IIIC (T1 or T2, N2c, M0):

• Cancer is in the vulva or perineum or both (T1) and may be growing into the anus, lower vagina, or lower urethra (T2)
• The cancer has spread to nearby lymph nodes and has started growing through the outer covering of at least one of the lymph nodes (called extracapsular spread; N2c)
• The cancer has not spread to distant sites (M0)

In FIGO, this stage is also called IIIC.

Stage IV is subdivided into 2 stages that are termed as Stage IVA and Stage IVB.

• Stage IVA: Either of the following -
• T1 or T2, N3, M0:
  • Cancer is in the vulva or perineum or both (T1) and may be growing into the anus, vagina, or lower urethra (T2)
  • Cancer spread to nearby lymph nodes has caused them to be stuck (fixed) to the underlying tissue or caused open sores (ulceration) (N3)
  • It has not spread to distant sites

In FIGO, this stage is also called IVA.

OR

• T3, any N, M0:
  • The cancer has spread beyond nearby tissues to the bladder, rectum, pelvic bone, or upper part of the urethra (T3)
  • It may or may not have spread to nearby lymph nodes (any N). It has not spread to distant sites (M0)

In FIGO, this stage is also IVA.

• Stage IVB (any T, any N, M1):
• Cancer has spread to distant organs or lymph nodes (M1)
• This is the most advanced stage of cancer

In FIGO, this stage is also IVB.

(Source: “The FIGO/AJCC system for staging vulvar cancer”; information provided by the American Cancer Society, February 2016)

Vulvar cancers are treated using several methods depending on the stage of the cancer:

In situ and initial stage cancers: Stage 0 and Stage I

• Vulvar intraepithelial neoplasia (VIN, or vulvar precancer) may be treated using topical applications, laser surgery, or local excisional surgery
• A lesser-invasive procedure, called ultrasound surgical aspiration, may be used to break the tumor into smaller segments and destroy them using ultrasound vibrations
• In some cases, a minor procedure known as skinning vulvectomy may be undertaken, which is followed through by surgical skin grafts to cover the surgery site
• Stage I cancers are removed either through wide local excisional surgery or radical local excisional surgery. In case lymph node involvement is noted, then the local lymph nodes are also removed
• Radiation therapy may be an option for individuals in whom surgical intervention is not possible

Higher stage cancers: Stage II to Stage IV

• Large-sized tumors may be removed through radical vulvectomy, modified radical vulvectomy, or by performing a radical local excisional surgery. In case the lymph nodes are involved, then they are also removed
• Radiation therapy may be an option for individuals in whom surgical intervention is not possible, or following surgery to destroy the remaining cancer cells
• Chemotherapy may be considered before or following surgery, either independently, or in combination with radiation therapy
• Advanced stage cancers (stage IV) are treated through a combination of radical vulvectomy, pelvic exenteration (if necessary), and radation therapy and/or chemotherapy
• Individuals who cannot withstand radical surgical procedures may be treated by a combination of radation therapy and chemotherapy. They may also be recommended for clinical trials

Recurrent cancers are treated on a case-by-case basis based on their stage and site of recurrence. They are treated through radical vulvectomy and/or pelvic exenteration invasive techniques. Often, a combination of treatment measures may be used by the healthcare providers (including recommendation for clinical trials, when recurrence is associated with higher stage cancers). Advanced stage tumors with metastasis may be treated on a case-by-case basis; often symptomatic treatment with radiation and/or chemotherapy is attempted.

The treatment of Rhabdomyosarcoma of Vulva involves surgery, which is the most common treatment option considered.

Surgery:

• Vulvectomy: It is a surgical intervention technique to remove a part or the entire vulva. It may be of the following types:
  • If only the top layer of the skin over the vulva is removed, it is known as skinning vulvectomy. This procedure also involves the use of skin grafts (taken from other body sites) to cover surgical site
  • If only a portion of the vulva is removed, which may or may not be accompanied by removal of the affected lymph nodes; then, it is known as modified radical vulvectomy
  • If the entire vulva that is affected by cancer is removed, then it is called a radical vulvectomy. In such cases, the local lymph nodes are also removed. The entire vulva may include the clitoris and the inner and outer lips of the vagina
• Pelvic exenteration: It is an extensive surgical procedure wherein the entire vulva, the vagina, the surrounding tissues, and the pelvic lymph nodes are removed. In addition, depending on the extent of tumor spread, parts affected around the region (such as the cervix, urinary bladder, rectum, colon, etc.) may be removed. Recovery from this surgery usually takes a long period

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
• Chemotherapy may be used in addition to radiation and/or surgery, to treat cancers that have spread or recurred. When chemotherapy and radiation therapy are used together, it is called concurrent chemoradiation
• Side effects of chemotherapy may include nausea, vomiting, hair loss, loss of appetite, diarrhea, fatigue, increased risk of infection, mouth sores, and easy bruising, depending on the drugs 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 (internal radiation therapy or brachytherapy)
• Possible side effects may include:
  • Fatigue, nausea, vomiting, and diarrhea
  • Bladder irritation, leading to inflammation (cystitis)
  • Ovaries may be affected resulting in menstrual changes, or premature menopause
  • The vulva and vagina may be affected, causing soreness, or even scar tissue formation

Post-operative care is important and 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 Rhabdomyosarcoma of Vulva be Prevented?

• Current medical research has not established a way of preventing the formation of Rhabdomyosarcoma of Vulva
• 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 Rhabdomyosarcoma of Vulva? (Outcomes/Resolutions)

• The prognosis of Rhabdomyosarcoma of Vulva 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
  • Histological subtype of the tumor: A favorable subtype can help ensure a better prognosis
  • 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
  • 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
• With medical advancements and comprehensive treatment practices, the prognosis of Vulvar RMS has shown great improvement. The overall cure rates for the embryonal variant range from between 90-95% (per the WHO)
• 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 Rhabdomyosarcoma of Vulva:

Amongst pediatric soft tissue sarcomas (affecting children less than 15 years), rhabdomyosarcomas form the largest category of malignant tumors.