Langerhans cell histiocytosis is a non-neoplastic disease of unknown etiology. It is characterized by a clonal proliferation of Langerhans histiocytes, which are cells of the monocyte-macrophage lineage. Clinically, its manifestations range from isolated bone lesions to multisystem disease, with this latter form more likely to be seen in younger patients.
The most common manifestation of Langerhans cell histiocytosis is a localized or multifocal benign infiltration of bones by the Langerhans histiocytes, and this was formerly called eosinophilic granuloma. It usually affects the skull, proximal portion of the femur, mandible, ribs, and pelvis1,2. Between 7% and 25% of these patients have spinal involvement3,4, with the most frequent site of involvement being the thoracic vertebrae, followed by the lumbar and cervical regions1,4-6.
More than half of the cervical spinal lesions in pediatric patients with Langerhans cell histiocytosis affect the C3-C5 segment1,7,8, and involvement in the upper cervical spine is uncommon. There are very few published cases describing Langerhans cell histiocytosis of the atlas in children7,9-15.
We report on two pediatric patients who had Langerhans cell histiocytosis of the atlas that was treated nonoperatively, resulting in complete reconstitution of the bone. Our patients' families were informed that data concerning the cases would be submitted for publication, and they consented.
Case 1. A ten-year-old boy was admitted to our institution for evaluation of a two-month history of neck pain associated with slight restriction of head rotation. The neck pain was continuous and progressively increasing, and the use of nonsteroidal anti-inflammatory medication had resulted in no improvement.
Radiographs of the cervical spine revealed no abnormality. Technetium-99 methylene diphosphonate bone scintigraphy showed increased uptake on the left side of the upper cervical spine and no other skeletal lesions. A computed tomography scan revealed an osteolytic lesion in the left lateral mass of the atlas (Fig. 1-A). A computed tomography-guided percutaneous needle biopsy was performed, the results of which confirmed the diagnosis of Langerhans cell histiocytosis.
The patient wore a stiff cervical collar for three months. By the end of that time, the symptoms had resolved and he had regained full motion of the neck. A computed tomography scan performed six months later showed complete reconstitution of the lateral mass of the atlas (Fig. 1-B). At the time of the six-year follow-up, he continued to be free of symptoms and computed tomography studies showed no evidence of recurrence.
Case 2. A five-year-old girl presented with a three-week history of neck pain and torticollis. She was afebrile. The physical examination revealed pain with motion of the cervical spine. The neurological examination revealed normal findings.
Radiographs showed only a lateral tilt of the cervical spine. A technetium-99 methylene diphosphonate bone scan showed increased uptake in the upper cervical spine and two more lesions, one at T4 and the other at L1. A computed tomography scan showed a lytic lesion in the left lateral mass of the atlas (Fig. 2-A), a complete collapse of the T4 vertebral body (vertebra plana), and a lytic lesion at L1. A computed tomography-guided percutaneous fine-needle biopsy of the lumbar lesion was performed, the results of which confirmed the diagnosis of Langerhans cell histiocytosis.
The patient wore a stiff cervical collar for three months and then wore a thoracolumbar spinal orthosis for six months due to a mild kyphosis caused by the T4 vertebral collapse.
After fourteen months of follow-up, the patient was free of pain and had full neck motion. At that time, a computed tomography scan revealed complete reconstitution of the lateral mass of the atlas (Fig. 2-B). In addition, T4 exhibited a vertebral height similar to the height of the uninvolved adjacent upper and lower vertebrae, and there was a complete reconstitution of the lytic lesion at L1.