Kolasa, K

Abstract When evaluating malignant anterior mediastinal masses, thymic carcinoma and lymphoma represent the most common etiologies. We present a case of a patient with an incidentally found anterior mediastinal mass, initially suspected to be thymic carcinoma, who was ultimately diagnosed with primary mediastinal classical Hodgkin lymphoma. A 55-year-old woman with no contributory past medical history presented to her primary care provider with several weeks of cough which was unresponsive to antibiotics and corticosteroids. A chest x-ray demonstrated a large mediastinal mass and subsequent CT chest further revealed an anterior mediastinal mass measuring 15 x 6 x 13 cm. A PET-CT showed intense FDG uptake in the mediastinal mass (SUVmax 14.5) and FDG-avid right pleural lesions suggestive of metastases (SUVmax 4.5). She was referred to outpatient pulmonary clinic. Given imaging findings, thymic carcinoma was initially favored. Following multidisciplinary discussion with Thoracic Surgery, neoadjuvant chemotherapy was recommended prior to any consideration of surgical resection given the size and involvement of mediastinal structures. Thus, CT-guided biopsy was pursued to confirm the diagnosis, but unexpectedly revealed classical Hodgkin lymphoma of the nodular sclerosis subtype. She was diagnosed with stage IVA disease and urgently initiated chemotherapy with nivolumab, doxorubicin, vinblastine, and dacarbazine (N-AVD). A repeat PET-CT two months after initiation of treatment demonstrated marked metabolic and anatomic response, with the mediastinal mass reduced to 8.9 x 5.4 cm with an SUVmax of 2.1. Similarly, the FDG-avid pleural metastases had a decrease in SUVmax to 1.0. The patient was continued on the same treatment regimen. Although thymic carcinoma was initially suspected, a biopsy was obtained because surgical resection was not planned as the initial step in management. Typically, thymic malignancies are not biopsied prior to surgery due to the risk of tumor seeding and the preference for definitive resection, with some exceptions. In this case, the decision to biopsy resulted in the unexpected diagnosis of primary mediastinal classical Hodgkin lymphoma, a particularly rare entity among anterior mediastinal masses. This case underscores the importance of individualized diagnostic strategies and the role of tissue confirmation when clinical or therapeutic circumstances deviate from standard practices. This abstract is funded by: None

Abstract Plasmacytomas are a form of plasma cell malignancy which can occur as isolated lesions or as part of systemic multiple myeloma. We present a case of a patient whose evaluation for an incidentally found lung mass led to the diagnosis of multiple myeloma. A 65-year-old man with no remarkable past medical history presented to the emergency department with two days of fever, cough, and chills. A chest x-ray demonstrated findings suggestive of pneumonia as well as a “smoothly marginated density in the left lung apex.” CT chest further revealed a destructive mass involving the left third rib measuring 7.6 x 4.6 cm; it was difficult to determine from imaging if the mass originated from the lung, pleura, or bone. PET-CT showed significant FDG avidity of the mass (SUVmax 40.2) and FDG-avid left mediastinal and supraclavicular lymph nodes. He subsequently presented to outpatient pulmonary clinic for further evaluation. Given imaging findings, primary lung malignancy or soft tissue sarcoma was initially suspected. He underwent CT-guided biopsy of the mass with pathology showing a kappa light chain-restricted plasmacytoma. Serum studies demonstrated a markedly elevated kappa/lambda ratio of 132. Bone marrow biopsy confirmed a kappa light chain-restricted plasma cell myeloma with 20% plasma cells. On review of previous labs, the patient was noted to have anemia (hemoglobin 11.9 g/dL) previously attributed to iron deficiency anemia as well as hypercalcemia (10.3 mg/dL). Renal function was normal. He was diagnosed with multiple myeloma and started on daratumumab, bortezomib, lenalidomide, and dexamethasone (Dara-VRD), with favorable response to treatment. The presence of plasmacytomas is clinically important to recognize in multiple myeloma as they are predictors of poorer outcomes. The site of origin also carries prognostic implications: paraskeletal plasmacytomas arising from bone marrow are associated with better outcomes than extramedullary plasmacytomas which result from hematogenous spread. In one study, paraskeletal plasmacytomas were found to occur in 17.6% of patients with multiple myeloma, with 40% located in the chest; similarly, extramedullary plasmacytomas were associated with the lungs or pleura in 23% of patients. Altogether, this case underscores the importance of considering plasmacytomas in the differential of a lung mass, particularly if there is osseous involvement. This abstract is funded by: None

Abstract Rationale Gastroesophageal reflux disease (GERD) is a common comorbidity in non-cystic fibrosis bronchiectasis (NCFB), yet its impact on clinical outcomes remains poorly defined. We sought to determine whether GERD is associated with worse clinical outcomes in patients with NCFB using a large, real-world database. Methods We conducted a retrospective cohort study using the TriNetX platform, identifying patients with NCFB (ICD-10 J47*) with and without concurrent GERD (ICD-10 K21*), excluding those with cystic fibrosis (ICD-10 E84*). Propensity score matching (PSM) was performed using 1:1 nearest neighbor matching without replacement, controlling for age, sex, race/ethnicity, obesity, socioeconomic risk factors, and tobacco use. Primary outcomes included pneumonia, bronchiectasis exacerbations, intensive care unit admission, mechanical ventilation, and mortality. Statistical analyses included risk ratios and Cox proportional hazards modeling for survival outcomes. Results Out of 421,710 patients with NCFB in the dataset from January 2000 to September 2025, 186,874 (44%) had a diagnosis of GERD. After propensity score matching, 179,753 patients with NCFB+GERD and 179,753 patients with NCFB-only were included (mean age 74.0±13.1 years, 58.8% female, 67.1% White). Baseline characteristics were well-balanced after matching. Median follow-up was approximately 2.5 years for both cohorts (898 vs 889 days; similar means and IQR), ensuring balanced observation time. Compared to NCFB-only, NCFB+GERD was associated with increased risks for mortality (risk ratio 1.04, 95% CI 1.02-1.05; p < 0.001), pneumonia (risk ratio 1.06, 95% CI 1.05-1.08; p < 0.001), bronchiectasis exacerbations (risk ratio 1.03, 95% CI 1.01-1.06; p = 0.006), and mechanical ventilation (risk ratio 1.14, 95% CI 1.10-1.18; p < 0.001). Intensive care unit admission rates were comparable between groups (risk ratio 1.00; p = 0.65). Conclusions In this large propensity score-matched analysis, concurrent GERD in NCFB is independently associated with increased mortality, pneumonia, bronchiectasis exacerbations, and mechanical ventilation requirements. These findings suggest GERD may represent a modifiable risk factor warranting aggressive management in NCFB patients. Study limitations include retrospective design, reliance on ICD-10 coding accuracy, and potential unmeasured confounders. Our results support systematic screening and treatment of GERD in NCFB, but whether targeted GERD management can modify the natural history of NCFB future investigation. This abstract is funded by: None