Surgical resection of pulmonary crystal-storing histiocytosis with Sjögren's syndrome: A case report

INTRODUCTION AND IMPORTANCE: Crystal-storing histiocytosis (CSH) is a rare clinical entity characterized by an abnormal increase in the number of histiocytes with massive accumulation of crystallized immunoglobulins. Yano et al. reported only one case of gastric CSH associated with Sjögren's syndrome. In this report, we present a case of pulmonary CSH with Sjögren's syndrome, and discuss the relevant literature. CASE PRESENTATION: A 64-year-old woman who had never smoked presented with cough 2 years earlier. Chest CT showed that the nodule in the right lower lobe had slowly enlarged to 12 × 10 mm. We suspected primary lung cancer and performed video-assisted thoracoscopic right S6 segmentectomy. Histopathological evaluation of the resected specimen revealed crystal-storing histiocytosis. As of 6 months postoperatively, no recurrence has been identified. CLINICAL DISCUSSION: Eighteen cases of pulmonary CSH have been described in the English language peer-reviewed literature, including our case. In this case, the patient had a history of Sjögren's syndrome, but no lymphoproliferative or plasma cell disorder (LP-PCD). Therapy for all patients without LP-PCD was excisional resection of the lung. Treatment and prognosis of patients with CSH varied according to the defined pathology. Jones et al. reported the case of 54-year-old woman without LP-PCD who presented with a solitary asymptomatic focus of CSH in the lung and initially underwent lesion resection, but showed recurrence 10 years later. CONCLUSION: Pulmonary CSH is one differential diagnosis for pulmonary nodule enlargement in patients with autoimmune disease. Surgical resection appears to represent an effective therapeutic option for localized CSH, but long-term follow-up remains necessary.