Sacrococcygeal teratoma

Key points

Arises from Hensen’s node in the embryonic primitive streak

1 in 35,000 - 40,000 live births

4:1 female to male

Familial if Currarino triad (autosomal dominant) - exclusively pre-sacral

MYCN gene amplification, distal 10q trisomy syndrome, mosaic trisomy

Antenatal features

Risk of high output cardiac failure and non-immune hydrops in utero

Risk of maternal mirror syndrome - oedema, hypertension, pre-eclampsia

MRI if diagnosis in doubt

Tumour volume to foetal weight ratio (TFR)

Tumour measured in 3 dimensions, divided by foetal weight measured on USS

If >0.12 = 80% hydrops and 60% mortality

If <0.12 = 100% survival

Differential Diagnoses

• Myelomeningocele

• Lipoma

• Lumbosacral haemangioma

• Caudal regression syndrome

  
  

Prognostic Factors

• Cardiac failure

• Gestational age at diagnosis

• Tumour growth rate

• Haemorrhage or necrosis

In Utero Interventions

1. Maternal Steroids

To delay preterm delivery and reduce inflammatory response.

2. Amnioreduction

For severe polyhydramnios to reduce discomfort and labour risk

3. Fetoscopic Laser Ablation

Indication: Large vascular SCT with hydrops

Procedure: Laser coagulation of tumour-feeding vessels.

Risks: PPROM, preterm labour, incomplete devascularisation

4. Radiofrequency Ablation

Indication: Hydrops

Procedure: Coagulative necrosis via localised heat

5. Open Foetal Surgery

For large tumours threatening intrauterine demise

6. EXIT (Ex Utero Intrapartum Treatment)

Indication: Obstructed airway or haemodynamic instability at birth.

Procedure: Partial delivery with placenta intact to establish airway or reduce tumour bulk before cord clamping.

8. Postnatal Management

Initial Care

Prone positioning

Resuscitation and stabilization

Bloods: FBC, U&E, clotting, AFP

Vitamin K administration

Imaging and planning

Altman Classification

Type I

• Completely external

• 47% of cases

Type II

• Predominantly external with significant intra-pelvic component

• 34% of cases

Type III

• Predominantly intra-pelvic with an external component extending into the abdomen

• 9% of cases

Type IV

• Entirely internal

• 10% of cases

Histopathological Classification

Mature Teratoma

• Composed of well-differentiated elements from all 3 germ layers

• Most common in neonates; benign

• Excellent prognosis after complete resection with coccygectomy

Immature Teratoma

• Contains embryonic tissues (e.g., neuroectoderm)

• Potentially malignant, especially in older infants

• Requires close monitoring

Malignant Teratoma

• Contains overt malignancy (e.g., yolk sac tumour)

• Requires surgery + chemotherapy

Complications

>10 cm - 50% mortality

Yolk sac tumour most common malignant transformation, but can be other GCT

11% recurrence due to incomplete macro- or microscopic resection, unresected coccyx, tumour rupture, age, and immature/malignant histology

Approx 30% neurogenic bladder + constipation

7% faecal incontinence

Sexual function mostly normal

Cosmetic dissatisfaction in most

Limb function normal - but compensatory gait in some

Standard scenario

Concerns:

1. Achieving an oncological resection due to possible yolk sac elements

2. Mass effect and cardiac failure

If antenatal presentation

Calculate TFR

Look for non-immune hydrops

Can open hysterotomy and resect if hydrops up to 26 weeks

Early delivery weeks 27-32 if hydrops

If large cyst - can be aspirated to ease delivery

Consider if size of tumour puts risk of dystocia

EXIT + resect if highly vascular tumour

If postnatal presentation

Ensure stable and managed on neonatal unit

Nurse on side

History

Look for above on antenatal features

Examination

Size of mass, where to resect

Press on mass and check for bulging fontanelle - meningocoele

Look for oedema

Dysmorphic features

Investigations

aFP to look for yolk sac tumour elements

USS/MRI for Altman stage

Echo for heart failure

Management

Altman I + II - Sacral approach

III - abdo + sacral

IV - abdo

Preoperative Preparation

• Imaging: MRI/US to assess extent

• Tumour markers: AFP, β-HCG

• Blood preparation for high vascular tumours

• Prophylactic antibiotics

Surgical Steps

1. Place Heger in rectum

2. Incision: Midline vertical or chevron; elliptical for thin skin over tumour

3. Tumour Exposure: Dissection in avascular planes, vessel control

4. Coccyx Identification: Coccygectomy is mandatory to reduce recurrence

5. Tumour Resection: En bloc with coccyx; preserve rectum, urethra, and anus

6. Haemostasis: Inspect for bleeding; careful vessel ligation

7. Control middle sacral artery - if bleeding and retracted - options: Pack, close and come back in 48 hours after seeking other opinions, or flip patient, open abdomen and control aorta

   Avoid pelvic splanchnic nerves from sacral plexus

   Pressure if presacral veins bleeding

8. Closure: Layered wound closure; insert drains if necessary

Chemotherapy is not utilised for mature and immature SCT or completely resected malignant SCT

Chemotherapy only for metastases/malignant recurrence

Follow up

Page edited by Prof. Ashok Daya Ram MBBS, FRCS, FRCPS, FEBPS, FRCS (Paed Surgery), Consultant Paediatric and Neonatal Surgeon, Norfolk and Norwich University Hospital, Norwich, UK. October 2025

References

Sun, Raphael C, et al. "Sacrococcygeal Teratoma." Pediatric Surgery NaT, American Pediatric Surgical Association, 2023. Pediatric Surgery Library, www.pedsurglibrary.com/apsa/view/Pediatric-Surgery-NaT/829143/all/Sacrococcygeal_Teratoma.

Rodriguez MA, Cass DL, Lazar DA, Cassady CI, Moise KJ, Johnson A, Mushin OP, Hassan SF, Belleza-Bascon B, Olutoye OO. Tumor volume to fetal weight ratio as an early prognostic classification for fetal sacrococcygeal teratoma. J Pediatr Surg. 2011 Jun;46(6):1182-5. doi: 10.1016/j.jpedsurg.2011.03.051. PMID: 21683219.

Altman RP, Randolph JG, Lilly JR. Sacrococcygeal teratoma: American Academy of Pediatrics Surgical Section Survey-1973. J Pediatr Surg. 1974 Jun;9(3):389-98. doi: 10.1016/s0022-3468(74)80297-6. PMID: 4843993.