Related Experiment Video
Updated: Aug 10, 2025
A Protocol for Rapid Post-mortem Cell Culture of Diffuse Intrinsic Pontine Glioma DIPG
Published on: March 7, 2017
Diffuse pulmonary meningotheliomatosis with pan-TRK expression by immunohistochemistry: a novel finding and potential
Cansu Karakas1, Michael A Nead2, Moises J Velez3
1Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA.
Background:
Pulmonary meningothelial-like nodules (PMNs) are benign proliferations of unclear clinical significance. They are mainly asymptomatic lesions that are usually discovered during the pathologic evaluation of resected pulmonary specimens or following post-mortem examination. Diffuse pulmonary meningotheliomatosis (DPM), which presents as bilateral multiple PMNs throughout the lungs, has been described less frequently. DPMs are benign lesions associated with both neoplastic and non-neoplastic pulmonary conditions.
Case Presentation:
We report the case of a 59-year-old female patient who presented with a history of cough. Computerized tomography (CT) imaging revealed multiple subcentimeter bilateral pulmonary nodules. transbronchial biopsies were obtained which revealed foci of nodular interstitial proliferations composed of epithelioid to spindled cells in a vague whorled pattern. Immunohistochemical stains were diffusely positive for EMA and progesterone receptor. Furthermore, pan-TRK exhibited strong and diffuse membranous expression in the lesional cells. INSM1 was negative for expression. RNA-based next-generation sequencing for the detection of NTRK fusions was performed and was negative for gene rearrangements involving NTRK1, NTRK2, and NTRK3.
Conclusion:
Here, we report a rare case of DPM and report pan-TRK expression in PMNs which has not been described. We provide a brief review of the literature and provide insight into the potential physiologic nature of PMNs. Lastly, we emphasize the recognition of pan-TRK immunoexpression in PMNs to avoid potential diagnostic errors.
Insights
Diffuse pulmonary meningotheliomatosis (DPM) is rare, often asymptomatic lung condition. This case highlights pan-TRK expression in pulmonary meningothelial-like nodules (PMNs), aiding diagnosis and avoiding errors.
Area of Science:
- Pulmonology
- Pathology
- Oncology
Background:
- Pulmonary meningothelial-like nodules (PMNs) are benign lung lesions of uncertain clinical significance.
- Diffuse pulmonary meningotheliomatosis (DPM) presents as widespread PMNs and is infrequently documented.
- DPM is associated with various neoplastic and non-neoplastic lung conditions.
Approach:
- A case study of a 59-year-old female patient with cough and bilateral pulmonary nodules.
- Diagnostic methods included CT imaging, transbronchial biopsies, and immunohistochemical staining.
- RNA-based next-generation sequencing was performed to detect NTRK fusions.
Key Points:
- Histopathology revealed nodular interstitial proliferations with epithelioid to spindled cells.
- Immunohistochemistry showed diffuse positivity for EMA and progesterone receptor.
- Significant finding: pan-TRK exhibited strong, diffuse membranous expression in lesional cells, while INSM1 was negative.
- NTRK gene rearrangements were absent.
Conclusions:
- This report details a rare case of DPM with previously undescribed pan-TRK expression in PMNs.
- The findings offer insights into the potential physiologic nature of PMNs.
- Emphasizes recognizing pan-TRK immunoexpression to prevent diagnostic misinterpretations.
