Isolated skeletal Langerhans cell histiocytosis in adults: A case report.

INTRODUCTION AND IMPORTANCE: LCH in adults is rarely encountered, with the preference in children and axial skeleton as predilection site. Limited understanding of adult LCH causes frequent misdiagnosis, as our experience in an adult case of LCH threw off our differential diagnosis. CASE PRESENTATION: A 21-year-old male was referred to our hospital due to pain in his right shoulder. Plain radiograph and MRI showed a solitary well-marginated lytic lesion on the distal third of the clavicle. Together with a clear history and physical exam, the benign bone cyst was suspected and we performed an open biopsy simultaneously with curettage followed by internal fixation using a bone graft. Pathology and immunohistochemistry dismissed our suspicion and confirmed LCH as the main diagnosis. At six months post-surgery, no signs of recurrence were seen on the fixated site nor complained by the patient. DISCUSSION: Diagnosing LCH involves considering imaging appearances and patient demographics as initial clues. However, confirming the diagnosis requires a biopsy with proven CD1 expression. Currently, the majority of studies recommend confirming the diagnosis before initiating therapy. This precaution is necessary due to the unclear pathophysiology of LCH, which complicates the implementation of specific therapies. Based on benign features of skeletal lesions found from imaging, invasive treatment before biopsy confirmation still gave a satisfactory outcome despite not being in line with the current recommendation. CONCLUSION: Excisional biopsy and curettage in solitary LCH yield satisfactory outcomes. However, further studies are needed with larger sample sizes and interventional designs.

Right Thigh Mass Metastasis from Lung Cancer Mimicking Primary Soft Tissue Sarcoma: A Case Report.

BACKGROUND Soft tissue metastases (STMs) are less common than bone metastases and sometimes misdiagnosed as primary soft tissue malignancies. Skin, lungs, and breast are the most common primary lesions of STMs and rarely the presenting symptoms. We present an STM from lung adenocarcinoma that became a presenting symptom in nonsmoking woman. CASE REPORT A 47-year-old woman presented to our hospital with a painful mass in her right thigh and weight loss of 10 kg for 4 months. Femoral radiograph revealed a lesion suggestive of bone sarcoma. However, magnetic resonance imaging (MRI) showed it was more likely a primary soft tissue sarcoma. A small mediastinal mass was noticed on preoperative chest radiograph, and the patient denied any symptoms except the mass in the right thigh. Our clinicopathological conference team decided to perform a biopsy of mediastinal and right thigh masses. Histopathology examinations confirmed the right thigh mass as soft tissue metastasis from mediastinal mass, confirmed as lung adenocarcinoma. We treated the patient with palliative care with zoledronic acid and gefitinib. At the 6-month follow-up, the patient's symptoms significantly improved, and MRI showed a marked size reduction. CONCLUSIONS Diagnosis of STM can be difficult when presenting as the primary manifestation. Failure to identify promptly can lead to rapid disease progression and unfavorable prognosis. Failure to diagnose primary malignancy during biopsy occurs in approximately 28% of cases. This report has the potential to facilitate the avoidance of unnecessary procedures and highlight the importance of using a multidisciplinary approach in managing cases with malignancy.

Classic and rare manifestations of multiple osteoma: A case report.

INTRODUCTION AND IMPORTANCE: Osteoma is a benign tumor that can arise from compact or cancellous bone and is more commonly found in the face or skull. The incidence of osteoma believed to be underreported as most are asymptomatic. To date, the best modality to diagnose osteoma is CT scan. We report a unique case of osteoma presenting with cranial and extracranial manifestations and highlight the importance of bone survey in evaluating patients with osteoma. CASE PRESENTATION: A 26-year-old female complained of bilateral pain in the jawbone and several areas of her head. On physical examination, there were several masses in the head with the largest on the left mandible measuring 5.6 × 6.0 × 4.5 cm from MSCT examination. Hemi-mandibulectomy, histopathological and cytopathology examination were performed on the tissue obtained from the left mandible which concluded osteoma. Post-operative bone survey was performed and found osteoma on left ulna and bilateral fibula. Suspected Gardner syndrome with multiple osteoma manifestation was excluded from normal results of colon in-loop examination. We conservatively monitored the patient and most recent 6-month follow-up found no complaint nor changes in the extracranial osteoma manifestation on left ulna and both fibulas. CLINICAL DISCUSSION: The benign tumor osteoma is incredibly uncommon to present both intra and extracranially. We suggest thorough skeletal studies such as bone survey to be performed as they are crucial in the full evaluation of patients with multiple osteomas. Osteoma treatment is based on the patient's symptoms, surgery for patients with symptoms and periodic monitoring for asymptomatic patients. CONCLUSION: It is necessary to consider radiological modality for diagnosing osteoma patients. The majority of osteomas are asymptomatic and the choice of radiological examination sometimes still misses the lesion. It is important to evaluate histologically if the lesion difficult to diagnose.