Superior vena cava syndrome (SVC) arises from a large mediastinal mass compressing the SVC obstructing its blood flow. It is life threatening associated with significant morbidity and mortality. Obstruction of SVC by invasion or external compression by pathologic process. As the flow of blood becomes obstructed, venous collaterals form. Collaterals may arise from the azygos,internal mammary, lateral thoracic paraspinous, and esophageal venous systems.

The cause of SVC can be extrinsic as seen in about 80 percent of cases or intrinsic e.g. vascular thrombosis. SVC syndrome is commonly seen in lymphomas, leukemia, neuroblastoma, germ cell tumor and sarcoma.

CLINICAL FEATURES

• Interstitial edema of the head, neck, and upper extremity

• Superior mediastinal syndrome (tracheal compression): cough, dyspnea, stridor, hoarseness, dysphagia, chest pain, syncope. Supine position makes symptoms worse.

• Cerebral edema can also occur and lead to cerebral ischemia, syncope, herniation, and possibly death.

• Hemodynamic compromise.

INVESTIGATION

• Chest X Ray - Reveals anterior superior mediastinal mass ± pleural/pericardial effusion.

• CT with contrast (or MRI) differentiates intrinsic from extrinsic SVC.

TREATMENT

• Elevate head of the bed to decrease edema.

• Avoid IV or IM medications in arms.

• Oxygen therapy is indicated.

• Glucocorticoids- dexamethasone.

• Initiate chemotherapy / radiotherapy.

• Surgery- stent placement.

This is a clinical syndrome accumulation of fluid in the pericardial space causing reduced ventricular filling and haemodynamic compromise. It is caused by tumors of the heart muscle and pericardium, leukemias, non-Hodgkin’s lymphoma, radiation pericarditis. It is rarely an early presentation of malignancy.

Signs and symptoms of Cardiac Tamponade

• Dyspnea / weakness ± chest pain

• Beck triad (hypotension, elevated jugular venous pressure, and a muffled/decreased heart sound)

• Narrow pulse pressure

• Friction rub

• Pulsus paradoxus > 10 mm Hg

• Low EKG QRS voltage ± pulsus alternans

Diagnosis

• Chest Xray - cardiac silhouette resembles a water filled balloon.

• Echocardiography: This shows pericardial effusion. Right atrium or ventricle collapse.

Treatment

• Needle catheter pericardiocentesis

• Radiation therapy

• Pericardiectomy

• Intrapericardial chemotherapy

Neoplastic epidural spinal cord compression (SCC) is a common complication that can cause pain and irreversible loss of neurologic function. May be at initial presentation or at relapse. Appropriate and prompt management can reverse deficits and prevent further devastating complications. Usually arise from metastasis to vertebra or direct extension from a paravertebral soft tissue mass

• Osteolytic >70%

• Osteoblastic 10%

• Mixed 20%

The causes of spinal cord compression include: Sarcoma, Neuroblastoma, Non-hodgkin’s lymphoma, germ cell tumor, spinal cord tumors or brain tumor metastases.

CLINICAL FEATURES

• Back pain, radicular pain. Children with cancer + back pain = spinal cord involvement until proven otherwise.

• Weakness

• Paraplegia/quadriplegia

• Sensory loss

• Urinary incontinence or retension

• Faecal incontinence

INVESTIGATION

• Spinal MRI can show vertebral collapse. The classical Dumb bell appearance can be seen.

TREATMENT

Supportive care -

• Dexamethasone (loading dose of 1-2 mg/kg IV, followed by 0.25-0.5mg/kg every 6 hours).

• Opiates for pain

• Bedrest

• Anticoagulation

• Prevention of constipation

Definitive treatment 

• Surgery

• Radiation therapy

• Chemotherapy

This results from a mass expanding in the cranial vault or from obstruction to CSF flow. Caused by tumor masses, Hemorrhage, thrombosis, abscesses or infarction.

Clinical Features

• Impaired consciousness

• Abnormal pupil size

• Nausea, vomiting

• Cushing reflex which includes increasing systolic while the diastolic blood pressure decreases, bradychardia and abnormal breathing.

Investigations are: • MRI, CT scan

TREATMENT

• Raise the head to 30 degrees.

• Hyperbaric oxygen

• Hyperventilation

• Mannitol

• Use of dexamethasone if ICP results from intracra nial tumors 

Gastrointestinal (GI) tumours can often cause mechanical small bowel obstruction either by intrinsic or extrinsic compression e.g. located in the colon, pancreas and stomach, or metastasis from distant disease. Tumours can also impair bowel motility by invasion of the celiac plexus. Patients usually present abdominal pain, vomiting, abdominal distension, constipation, fever, shock, death

Investigations include abdominal ultrasounds, plain abdominal X-rays, Abdominal CT scan.

TREATMENT

• GI decompression using a nasogastric tube,

• Adequate hydration

• Palliative surgery should only be considered in selected patient with limited metastatic disease

• Gastric outlet or colonic obstruction, endoscopic stent placement

• Somatostatin analog lanreotide in patients with inoperable bowel obstruction resulting from peritoneal metastasis.

In pediatric oncology, compressional or mechanical emergencies occur when tumors grow and press on vital structures, causing life-threatening complications. These emergencies are particularly critical in settings like sub-Saharan Africa, where access to healthcare may be limited, making early recognition and treatment vital.

Some common emergencies include:

Superior Vena Cava Syndrome (SVCS): Tumors in the chest, like lymphomas, can compress the superior vena cava, causing swelling of the face and upper body, difficulty breathing, and risk of respiratory failure. Prompt treatment with steroids and chemotherapy is crucial.

Spinal Cord Compression: Tumors affecting the spine can press on the spinal cord, leading to weakness, paralysis, or loss of bladder control. Without urgent treatment like steroids or surgery, the damage can become permanent.

Airway Obstruction: Tumors in the neck or chest can block the airways, causing severe breathing difficulties. This requires immediate intervention, often with steroids, chemotherapy, or even surgery, to restore airflow.

Intestinal Obstruction: Abdominal tumors can block the intestines, leading to severe pain, vomiting, and inability to pass stool. This requires urgent medical care to prevent serious complications.

In sub-Saharan Africa, where healthcare infrastructure may be strained, addressing these emergencies requires rapid diagnosis and a multidisciplinary approach, including the use of steroids, chemotherapy, and, where available, surgical interventions. Raising awareness among healthcare workers and families about the early signs of these emergencies can help prevent delays in treatment and improve outcomes for affected children.