Sacrococcygeal teratoma

Sacrococcygeal teratoma
Specialty	Oncology

Sacrococcygeal teratoma (SCT) is a type of tumor known as a

12% of the time, and the remainder are considered "immature teratomas" that share benign and malignant features. Benign sacrococcygeal teratomas are more likely to develop in younger children who are less than 5 months old, and older children are more likely to develop malignant sacrococcygeal teratomas.

The

gene, consists of a presacral mass (usually a mature teratoma or anterior meningocele), anorectal malformation and sacral dysgenesis.

Presentation

Complications

Maternal complications of pregnancy may include

Complications of the mass effect of a teratoma in general are addressed on the

]

Later complications of the mass effect and/or surgery may include

however, the most frequent complication was an unsatisfactory appearance of the surgical scar.

Late effects

Late effects are of two kinds: consequences of the tumor itself, and consequences of surgery and other treatments for the tumor.^[citation needed]

Complications of not removing the coccyx may include both recurrence of the teratoma^[7] and metastatic cancer.^[7][8] Late malignancies usually involve incomplete excision of the coccyx and are adenocarcinoma.^{[citation needed]}Although functional disability in survivors is common,^[9] a small comparative study^[10] found a nonsignificant difference between SCT survivors and a matched control group.

In rare cases, pelvic scarring may necessitate that a

Cause

SCT is seen in 1 in every 35,000 live births, and is the most common tumor

and the increasingly routine use of prenatal ultrasound exams has dramatically increased the number of diagnosed SCTs presenting in fetuses. Like other teratomas, an SCT can grow very large. Unlike other teratomas, an SCT sometimes grows larger than the rest of the fetus.

Sacrococcygeal teratomas are the most common type of

Historically, sacrococcygeal teratomas present in 2 clinical patterns related to the child's age, tumor location, and likelihood of tumor malignancy. With the advent of routine prenatal ultrasound examinations, a third clinical pattern is emerging.

• urinary bladder
  and other organs, but large fetal SCTs frequently produce maternal complications which necessitate non-routine, investigative ultrasounds.
• Neonatal tumors present at birth protruding from the sacral site and are usually mature or immature teratomas.
• Among infants and young children, the tumor presents as a palpable mass in the sacropelvic region compressing the bladder or rectum.[15] These pelvic tumors have a greater likelihood of being malignant. An early survey found that the rate of tumor malignancy was 48% for girls and 67% for boys older than 2 months at the time of sacrococcygeal tumor diagnosis, compared with a malignant tumor incidence of 7% for girls and 10% for boys younger than 2 months at the time of diagnosis. The pelvic site of the primary tumor has been reported to be an adverse prognostic factor, most likely caused by a higher rate of incomplete resection.
• In older children and adults, the tumor may be mistaken for a
  pilonidal sinus
  , or it may be found during a rectal exam or other evaluation.

Diagnosis

During

, an SCT having an external component may appear as a fluid-filled cyst or a solid mass sticking out from the fetus' body. Fetal SCTs that are entirely internal may be undetected if they are small; detection (or at least suspicion) is possible when the fetal bladder is seen in an abnormal position, due to the SCT pushing other organs out of place.

At

.

Some SCTs are discovered when a child begins to talk at about age 2 years and complains of their bottom hurting or feeling "poopy" when they ride in a car seat.

Other tumors can occur in the sacrococcygeal and/or presacral regions

.

Smaller SCTs with an external component, seen in prenatal ultrasounds or at birth, often are mistaken for spina bifida.^{[citation needed]} Cystic SCT and terminal myelocystocele are especially difficult to distinguish; for more accurate diagnosis, MRI has been recommended.^[19]

Treatment

The preferred first treatment for SCT is complete surgical removal (i.e., complete resection). The preferred approach to a small SCT is through the perineum; a large SCT may require an additional approach through the abdomen. Resection should include the coccyx and may also include portions of the sacrum. The surgery should include reattachment of the small muscles and ligaments formerly attached to the coccyx, in effect reconstructing the posterior perineum. If not, there is an increased risk of perineal hernia later in life.

SCTs are classified morphologically according to their relative extent outside and inside the body:

• Altman type I — entirely outside, sometimes attached to the body only by a narrow stalk
• Altman type II — mostly outside
• Altman type III — mostly inside
• Altman type IV — entirely inside; this is also known as a presacral teratoma or retrorectal teratoma

The Altman type is significant in the contexts of management of labor and delivery, surgical approach, and complications of SCT. Serial ultrasound and MRI monitoring of SCTs in fetuses in utero has demonstrated that the Altman type can change over time. As the tumor grows, it can push between other organs and through the perineum to the body surface where the tumor appears as a bulge covered only by skin. Sometimes, the tumor bulge later slips back inside the perineum.

Like all

.

Management of fetal SCTs

Management of most fetal SCTs involves watchful waiting prior to any treatment. An often used decision tree is as follows:

• Perform detailed ultrasound exam including fetal
  Doppler flow analysis
  • If fetal
    high output failure, placentomegaly, or hydrops
    • If fetus not mature, perform
      fetal intervention
    • Else fetus mature, perform emergency
      Cesarean section
  • Else no emergent problems, perform serial
    non-stress tests and ultrasound biophysical profiles
    and plan delivery, as follows
    • If emergent problems develop, return to top of decision tree
    • Else if SCT over 5–10 cm or polyhydramnios, perform early (37 weeks gestation) elective Cesarean section
    • Else SCT small and no complications, permit term
      spontaneous vaginal delivery

Emergent problems include maternal mirror syndrome, polyhydramnios, and preterm labor. Poor management decisions, including interventions that are either premature or delayed, can have dire consequences.^[20][21] A very small retrospective study of 9 babies with SCTs greater than 10 cm diameter reported slightly higher survivorship in babies remaining in utero slightly longer.^[22]

In many cases, a fetus with a small SCT (under 5 or 10 cm) may be delivered vaginally.^{[23][24][25][26]} Prior to the advent of prenatal detection and hence scheduled C-section, 90% of babies diagnosed with SCT were born full term.^[27]

Management of adult SCTs

SCTs are very rare in adults, and as a rule these tumors are benign and have extremely low potential for malignancy. This estimation of potential is based on the idea that because the tumor existed for decades prior to diagnosis, without becoming malignant, it has little or no potential to ever become malignant. For this reason, and because coccygectomy in adults has greater risks than in babies, some surgeons prefer not to remove the coccyx of adult survivors of SCT. There are case reports of good outcomes.^[28]

See also

• Sacrococcygeal symphysis

References

External links