Robotic navigational bronchoscopy with cryobiopsy established the diagnosis of primary pulmonary follicular lymphoma in a 77-year-old female after initial cytology was nondiagnostic.
Case Report (n=1)
This case highlights the diagnostic challenge of primary pulmonary follicular lymphoma, emphasizing the need for detailed clinicopathologic correlation and flow cytometry when initial cytology is nondiagnostic.
Abstract Introduction Primary pulmonary lymphoma (PPL) represents clonal lymphoid proliferation confined to the lung parenchyma and/or bronchi without extrapulmonary involvement at diagnosis or within 3 months thereafter. PPL accounts for only 3-4% of extranodal non-Hodgkin lymphoma. The majority are mucosa-associated lymphoid tissue (MALT) lymphomas, followed by diffuse large B-cell lymphoma. Primary pulmonary follicular lymphoma (PPFL) is an exceptionally rare PPL subtype, reported in 1 (2%) out of 50 PPL cases in a retrospective review. We present a case of PPFL incidentally discovered during evaluation for abdominal pain. Case Presentation A 77-year-old female with hypertension, hyperlipidemia, hypothyroidism, osteopenia, breast cancer status post mastectomy and severe kyphoscoliosis presented with vague abdominal pain. Abdominal ultrasound revealed mild right hydronephrosis and a left lower-pole renal lesion; subsequent CT abdomen/pelvis demonstrated a partially visualized left lower-lobe pulmonary mass. Contrast-enhanced CT chest revealed a 1.8 × 2.8-cm left infrahilar mass, multiple subcentimeter bilateral nodules and mediastinal adenopathy. She reported fatigue, anorexia and a 40-lb unintentional weight loss over three years. She was a lifelong nonsmoker with no known carcinogen exposure. PET/CT demonstrated a hypermetabolic spiculated left lower-lobe mass with hypermetabolic left hilar and mediastinal lymph nodes. Endobronchial ultrasound-guided biopsies of nodal stations 4R, 4L and 11L showed initially reactive cytology; however, flow cytometry detected a lambda-restricted B-cell population (CD19+, CD20+, CD22+, dim CD10+, CD5−, CD38+), concerning for B-cell lymphoproliferative disorder. Given discordance between cytology and flow cytometry, robotic navigational bronchoscopy with cryobiopsy of the left lower-lobe lesion was performed. Histology demonstrated low-grade B-cell lymphoma and flow cytometry again confirmed a monoclonal lambda-restricted CD10+ B-cell population. Combined lung and nodal flow cytometry established PPFL. Absence of extrathoracic disease supported primary pulmonary involvement. She was referred to Hematology-Oncology who initiated bendamustine-rituximab. Discussion PPFL is rare and may be asymptomatic or present with nonspecific respiratory symptoms. Radiographic findings include solitary or multiple nodules, masses, reticulonodular opacities or lymphangitic patterns. Definitive diagnosis requires adequate tissue sampling and immunophenotyping. This case highlights the diagnostic challenge of PPFL: initial cytology was nondiagnostic and correlation with flow cytometry prompted repeat biopsy. Localized PPFL may be managed surgically or with radiotherapy, while disseminated disease is treated with chemotherapy regimens similar to nodal follicular lymphoma (e.g., bendamustine-rituximab). Conclusion Isolated cases of PPFL are described in larger series and reviews, highlighting its rarity and the need for detailed clinicopathologic correlation. Awareness of this entity is important to avoid misdiagnosis and guide appropriate treatment. This abstract is funded by: None
Gavankar et al. (Fri,) conducted a case report in Primary Pulmonary Follicular Lymphoma (n=1). bendamustine-rituximab was evaluated. Robotic navigational bronchoscopy with cryobiopsy established the diagnosis of primary pulmonary follicular lymphoma in a 77-year-old female after initial cytology was nondiagnostic.