TUmors 101: Introduction to Soft Tissue and Bony Tumors
Pediatric tumors of the upper limb are most commonly benign lumps that are not dangerous. The word tumor is derived from a word meaning swelling, but we use it today to describe any lump or bump in the body. Tumors are either benign or malignant. Benign tumors can be anything from a fluid filled sack called a cyst to an abnormal bone or cartilage growth. Benign tumors are typically nothing to worry about, and most can be managed with observation. Some can cause pain and/or limit motion and need to be removed. A few benign tumors can be locally invasive and agressive, requiring wide surgical resection with a risk of local recurrence (the tumor coming back). Malignant tumors (also known as cancers) are more concerning but rare in children. Malignant tumors are not only more locally invasive, but many have a risk of metastasis to other parts of the body, most commonly the liver and the lungs.
TUmors 201: Multiple Hereditary Exostoses (MHE)
Exostoses, also known as osteochondromas, are among the most common bone tumors in children. These tumors are often identified as incidental findings on X-rays taken for other reasons. Osteochondromas are outgrowths of bone with a cartilage cap that can be seen most commonly growing away from joints. Osteochondromas in the joints are known as Trevor’s disease. Some children can have many, or multiple exostoses throughout the body. Multiple exostoses are often the result of a genetic mutation that can occur spontaneously or be inherited from one parent as an autosomal dominant mutation. This means that if one parent has the mutation, their children have a 50% chance of having the mutation. For adults who are concerned about passing on the mutation to their child, there are safe and reliable methods to have children without passing on the mutation by selecting for embryos that do not have the mutation. This is done through a process known as PGD (preimplantation genetic diagnosis) along with IVF (in vitro fertilization). Although most children with MHE can lead a normal, pain-free life, some children with MHE can have severe limb deformities, pain, and limited function. Almost all children with MHE will require surgical removal and/or correction of limb deformities at some point in their childhood. Children with severe MHE tend to have short, broad limbs that can be confused with certain types of dwarfism such as achondroplasia.
Evaluation of the child with exostoses begins with a careful examination of the bones around the joints, as well as assessment of range of motion, pain, and tenderness. The initial examination may include x-rays of the entire body. An MRI of the entire spine is recommended as soon as the child is old enough to tolerate going into the scanner, usually around the age of 8, to make sure that there are no tumors that could pinch the nerves in the spinal cord. Any loss of neurologic function such as weakness, numbness, spasticity, or loss of bowel/bladder control should prompt an urgent MRI of the spine. If the child has no limitation in motion, deformity, or pain, observation is recommended.
Surgery is reserved for patients with progressive (worsening) deformities, joint pain, or loss of motion. Typically, this involves removal of the exostosis, as well as reshaping and lengthening the bones.
TUmors 202: Multiple Enchondromas (Ollier’s disease and Maffucci’s syndrome)
Nearly 1 in 3 people have an enchondroma inside one of their bones. Enchondromas are benign cartilage tumors that grow often unnoticed inside bones. Some enchondromas grow large enough to weaken the bone, and can cause a fracture, while most go undetected and never cause of problem. Children with multiple enchondromas, known as either Ollier’s disease or Maffucci’s syndrome, can have limitations in motion and loss of bone as the cartilage overgrows and replaces the bone. While single enchondromas are typically not a concern and if anything can be treated with curettage and grafting, Ollier’s and Maffucci’s should be treated agressively to remove as much of the tumors as possible before they lead to permanent deformities and limitations in function.