An unusual case of Langerhans Cell Histiocytosis (LCH)

A 46-year-old male presented with persisting shoulder ache and painful abduction of the arm bilaterally. CT of the shoulders and CT-HRCT of the lungs were performed, followed by bone scintigraphy and open lung biopsy.

The patient presented with persistent bilateral shoulder ache. Clinical examination revealed painful abduction of both arms, which was attributed to impingement syndrome. The patient was given analgesic and non-steroid anti-inflammatory treatment for a three months period, with no regression of symptoms. CT of the shoulders was performed. CT revealed a bilateral lytic lesion in the body of the scapula with smooth borders, thinning and disruption of the cortex, no discernible sclerotic rim and the presence of button sequestra. While scanning the shoulders some lung abnormalities were detected, which led to CT and HRCT scanning of the lungs. CT and HRCT showed multiple pulmonary nodules in upper lungs, some with cavitation. Bone scintigraphy showed increased uptake in the scapulae and no other bone lesion. Thoracotomy and open lung biopsy was performed. Histological examination confirmed the diagnosis of LCH.

Langerhans cell histiocytosis is a rare disease characterized by proliferation of histiocytes, resulting in focal or systematic manifestations. Combination of pulmonary and bone lesions is found in 4-20% of cases. Bone lesions are usually solitary (85%). The majority of cases are found in childhood. Bone involvement typically affects the flat bones (skull, pelvis and ribs), in more than half of the cases. Long bone involvement is seen in approximately 30% of cases. LCH involvement of bones typically presents as round or oval shaped lytic lesions with sharply defined borders, showing no sclerotic rim in the acute phase (sclerotic margin is observed in the healing phase). Button sequestra may be observed. Classical characteristic appearances of bone LCH are ‘geographic skull’ and ‘floating teeth’, resulting from extensive skull and mandible involvement respectively. Total collapse of an affected vertebral body may be seen, often referred to as ‘vertebra plana’. In bone scintigraphy the lesions present as regions of increased uptake. In 35% of the cases bone scintigraphy may be normal. Lung lesions are better appreciated with HRCT, especially in the early stages of the disease. The common pattern of lung involvement is that of small centrilobular nodules (1-5mm), some with cavitation, which may be associated with cysts. They are the result of peribronchiolar accumulation of Langerhans cells and eosinophils, formation of granulomas, and dilatation of the affected bronchioli. Progression of cavitary nodules to thick-walled and thin-walled cysts has been observed. Abnormalities involve predominantly the upper lung zones, with relative sparing of the costophrenic angles. In the late stages coalescence of cystic lesions and honeycombing may be present. There are three classic LCH syndromes, which present clinical overlap: (i) eosinophilic granuloma: involvement of bone, in patients 5-15 years old, (ii) Letterer-Siwe disease: diffuse involvement of the reticuloendothelial system in children younger than 2 years, with fulminant clinical course and (iii) Hand- Schüller-Christian disease: multiple bone lesions with extraskeletal involvement, usually in children 1-5 years-old.Combination of bone lesions with extraskeletal involvement (Hand- Schüller-Christian disease) in adults is extremely rare. Involvement of the scapula in LCH is rare.