Transformation of lymphoid interstitial pneumonia (LIP) into malignant lymphoma in patients with Sjogren's syndrome: a case report and literature review

A case of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma in a patient with a history of idiopathic lymphocytic interstitial pneumonia (iLIP)

BACKGROUND

Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma and idiopathic lymphocytic interstitial pneumonia (iLIP) are rare pulmonary diseases. MALT lymphoma is an extranodal marginal zone lymphoma (EMZL), whereas LIP is a benign lymphoproliferative disorder characterized by lymphocytic infiltration of the lungs. LIP should be closely monitored, as it has the potential to undergo malignant transformation into MALT lymphoma.

CASE PRESENTATION

A 45-year-old woman was diagnosed with LIP and followed up for 9 years before being referred to our hospital due to an enlarging shadow on chest radiographs. The volume of the sample collected via bronchoscopy was too small to make a diagnosis, so the patient underwent surgery. The pathology results revealed diffuse proliferation of medium-sized lymphocytes filling the alveolar spaces, leading to a diagnosis of MALT lymphoma. After a thorough examination, no other lesions were found, confirming the diagnosis of EMZL of the lung, a primary pulmonary lymphoma (PPL). No postoperative treatment was administered after surgery; however, 2 years later, recurrence was detected in the stomach, and the patient underwent chemotherapy. Complete remission was achieved through chemotherapy, and the patient has been recurrence-free for 3 years since her treatment.

CONCLUSIONS

We report a rare case of MALT lymphoma that developed 9 years after the diagnosis of LIP. Since LIP can undergo malignant transformation into EMZL, it is important to be aware of this possibility. Differentiating between the two diseases onthe basis ofclinical and imaging findings is challenging, so biopsytechniques, such as transbronchial biopsy, CT-guided needle aspiration biopsy, and surgical resection, are essential. While surgery is the standard treatment for primary pulmonary lymphoma, observation is a viable option, as it provides results comparable to those of other treatment approaches.

Marginal zone lymphoma of extranodal sites: A review with an emphasis on diagnostic pitfalls and differential diagnosis with reactive conditions

Marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) represents 8% of all B-cell lymphomas and it is the most common small B-cell lymphoma arising at extranodal sites. The gold-standard test to establish a diagnosis of MALT lymphoma remains histopathologic analysis with the aid of immunohistochemistry (IHC) and/or flow cytometry immunophenotypic analysis. MALT lymphoma represents a progression from a persistent chronic inflammatory process, and therefore distinguishing MALT lymphoma from chronic inflammation by histopathology may be challenging in some cases. Despite recent trends to consider IGH rearrangement/clonality as a confirmatory diagnostic test of MALT lymphoma, this method is far from ideal for this purpose since a positive or a negative result does not necessarily confirm or exclude that a process is lymphoma or reactive. This test must be correlated with the morphologic findings. Moreover, MALT lymphoma may arise in association with underlying autoimmune conditions where clonal lymphoid populations are not uncommonly detected. Therefore, we believe that an integrated approach including detailed morphologic review in combination with IHC and/or flow cytometry is best to establish a diagnosis of MALT lymphoma in most cases. We present helpful morphologic tips to avoid potential diagnostic pitfalls at some of the most common extranodal sites, including the stomach, ocular adnexa/conjunctiva, salivary gland, lung, thymus, breast, thyroid, small and large intestine and the dura. The differential diagnosis of MALT lymphoma with IgG4-related disease is also discussed.

Noninfectious Granulomatous Lung Disease: Radiological Findings and Differential Diagnosis

Granulomatous lung diseases (GLDs) are a heterogeneous group of pathological entities that can have different clinical presentations and outcomes. Granulomas are histologically defined as focal aggregations of activated macrophages, Langerhans cells, and lymphocytes, and may form in the lungs when the immune system cannot eliminate a foreign antigen and attempts to barricade it. The diagnosis includes clinical evaluation, laboratory testing, and radiological imaging, which especially consists of high-resolution computed tomography. bronchoalveolar lavage, transbronchial needle aspiration or cryobiopsy, positron emission tomography, while genetic evaluation can improve the diagnostic accuracy. Differential diagnosis is challenging due to the numerous different imaging appearances with which GLDs may manifest. Indeed, GLDs include both infectious and noninfectious, and necrotizing and non-necrotizing granulomatous diseases and the imaging appearance of some GLDs may mimic malignancy, leading to confirmatory biopsy. The purposes of our review are to report the different noninfectious granulomatous entities and to show their various imaging features to help radiologists recognize them properly and make an accurate differential diagnosis.

Lymphocytic interstitial non-HIV-related pneumonia in pediatrics: a case report

Lymphocytic interstitial pneumonia (LIP) in pediatric patients without human immunodeficiency virus (HIV) infection remains a poorly characterized and enigmatic disease. Immunological dysregulation, mutations in the COPA gene, and increased morbidity and mortality have been reported in these patients. We present a case of LIP in a pediatric patient without HIV infection. This patient was infected with human T-lymphotropic virus type 1 (HTLV-1) and required right lower lobectomy with pathological findings compatible with lymphocytic interstitial pneumonia. In addition, bronchiectasis, dermatological involvement, and malnutrition were documented. However, no autoimmune disease, polymyositis, myelopathy, or opportunistic infections were found. There were no abnormalities in cellular and humoral immunity. A genetic study identified heterozygous mutations in the SCNN1B, FCHO1, and IL7R genes using single exome sequencing of coding and splicing regions. Although these heterozygous variants are not reported to be aetiological for LIP or diagnostic for the patient's congenital immunodeficiency, we believe they are associated with the severe lung damage seen in the patient's case.

Undiagnosed Primary Sjögren's Syndrome With Pleural Involvement

Sjögren's syndrome (SS) is a systemic autoimmune disorder characterized by the lymphocytic infiltration of the exocrine glands, primarily the salivary and lacrimal glands, resulting in the dryness of the eyes and mouth. However, Sjögren's syndrome is not limited to glandular involvement, as it can also affect various other organ systems, leading to a wide range of extraglandular manifestations and delaying the diagnosis. In this scenario, a high level of suspicion is required.

Lymphocytic interstitial pneumonia presenting with a ground glass nodule: A case report and literature review

RATIONALE

Lymphocytic interstitial pneumonia (LIP) is a rare benign lymphoproliferative disorder, often associated with autoimmune diseases. Most LIPs present with multiple bronchial cysts and diffuse interstitial infiltration. It is histologically characterized by widespread diffuse lymphocytic infiltration of the pulmonary interstitium, and the enlargement and widening of the alveolar septum.

PATIENT CONCERNS

A 49-year-old woman was admitted to hospital for finding pulmonary nodules for more than 2 months. 3D imaging chest computed tomography (CT) examination of both lungs showed that there was a middle lobe of the right lung with a size of about 1.5 cm × 1.1 cm ground-glass nodules.

DIAGNOSES

A single operating port thoracoscopic wedge resection biopsy of a right middle lung nodule was performed. The pathology showed diffuse lymphocytic infiltration with varying numbers of small lymphocytes, plasma cells, macrophages and histiocytes infiltrating the alveolar septa, widened and enlarged alveolar septa, and scattered lymphoid follicles. Immunohistochemically, CD20 positive in follicular area, CD3 positive in interfollicular area. LIP was considered.

INTERVENTIONS

The patient was regularly followed without any specific treatment.

OUTCOMES

Follow-up chest CT showed no significant abnormalities in the lungs 6 months after surgery.

LESSONS

To the best of our knowledge, our case may be the second reported case of a patient with LIP presenting with a ground glass nodule on chest CT, and it is speculated that the ground glass nodule may be an early manifestation of idiopathic LIP.

Lymphangioleiomyomatosis and Other Cystic Lung Diseases

Cysts and cavities in the lung are commonly encountered on chest imaging. It is necessary to distinguish thin-walled lung cysts (≤2 mm) from cavities and characterize their distribution as focal or multifocal versus diffuse. Focal cavitary lesions are often caused by inflammatory, infectious, or neoplastic processes in contrast to diffuse cystic lung diseases. An algorithmic approach to diffuse cystic lung disease can help narrow the differential diagnosis, and additional testing such as skin biopsy, serum biomarkers, and genetic testing can be confirmatory. An accurate diagnosis is essential for the management and disease surveillance of extrapulmonary complications.