CASE 14586 Published on 22.04.2017

Pulmonary hyalinizing granuloma


Chest imaging

Case Type

Clinical Cases


Irene Cases Susarte, Remedios Rodríguez Mondejar, Irene Vicente Zapata, Maria Jesús Gayan Belmonte, Marta Tovar Pérez, Lucía Hernández Sánchez


63 years, male

Area of Interest Thorax, Lung, Abdomen ; Imaging Technique Conventional radiography, CT
Clinical History
A 63-year-old man came to the emergency department of our hospital with complaints of cough and dysphonia for 1 month. Our patient had no fever, weight loss, or history of cancer.
Imaging Findings
Chest radiograph revealed multiple well-defined lung nodules (Fig. 1). Subsequently, computed tomography (CT) of thorax-abdomen-pelvis was performed to rule out malignancy. CT showed several lung nodules in both lungs with variable size (from 4 millimetres to 2, 4 cm) (Fig. 2a, b, c). No lymphadenopathies or osseous erosion were observed. CT also revealed a perihepatic solid, heterogeneous mass with peripheral and central gross calcifications and two hypodense intrahepatic lesions (Fig. 2d). These findings suggested metastatic disease, so we performed: brain MRI, testicular and neck ultrasound, mammography, colonoscopy, all normal. Tumour markers and rheumatologic antibodies were also normal.
The biopsy of perihepatic mass revealed a benign fibrous tumour. Due to the absence of malignancy, a lung biopsy was performed and showed a pulmonary hyalinizing granuloma (PHG), without signs of malignant degeneration.
After 4 months, a follow-up CT was performance showing stability of all the findings.
PHG is a very rare fibrotic nodular disease whose aetiology remains unknown. It is related to an abnormal immune response and can be associated with extrapulmonary fibrotic conditions like sclerosing mediastinitis, retroperitoneal fibrosis or Riedel’s thyroiditis [1, 2, 3]. Our case was associated with a perihepatic mass (the other 2 intrahepatic hypodense lesions have not yet been characterized).

Most patients are asymptomatic and the disease is usually diagnosed as an incidental finding trough an image test. However, some individuals may suffer non-specific symptoms like cough, fever, fatigue or dyspnoea [1, 2, 3].
Chest radiographs show multiple (70%) or solitary (30%) nodules with well-defined borders, diameter ranging from 0.2 to 15cm (mean 2cm), bilateral and randomly distributed. Calcification and cavitation are not common. Nodules often remain stable for long periods, but they can grow slowly. Lymphadenopathies are not observed in this entity [1, 2, 3].
When these findings are present you should rule out a malignant metastatic disease or a primary (lung or lymphoma) tumour. Other possibilities are infection (tuberculosis, septic emboli or fungal infections), sarcoidosis, amyloidosis, silicosis, rheumatoid nodules, Wegener's granulomatosis, lymphomatoid granulomatosis, and plasma cell granuloma [1, 2, 3].
Final diagnosis is made by histopathological examination. Microscopically, a hypocellular network of concentric hyalinised collagen surrounded by a lymphocytic infiltrate is presented [1, 2, 3]. Macroscopically, whitish and well-defined nodules similar to a cotton-ball are characteristics [3].
This entity has a good prognosis. Nowadays, malignant degeneration has not been described. Treatment consists in resection and watchful waiting for solitary lesions or corticosteroid drugs in cases of multiple lesions [1, 2, 3].
In conclusion, PHG is a rare benign disease that can mimic a metastatic lung cancer. Biopsy is necessary for the diagnosis.
Differential Diagnosis List
Pulmonary hyalinizing granuloma
Malignant metastatic
Primary tumour
Infection (tuberculosis
septic emboli or fungal infections)
Rheumatoid nodules
Wegener's granulomatosis
Lymphomatoid granulomatosis
Plasma cell granuloma
Final Diagnosis
Pulmonary hyalinizing granuloma
Case information
DOI: 10.1594/EURORAD/CASE.14586
ISSN: 1563-4086