---
title: CHEST SEEK® Challenge Question
---

![A person in scrubs looks at a tablet. Text reads, "Increase Your Knowledge with CHEST SEEK®." On the right, a tablet and phone display medical images.](https://info.chestnet.org/hubfs/hubspot%20SEEK%20Library%20Campaign.png "A person in scrubs looks at a tablet. Text reads, \"Increase Your Knowledge with CHEST SEEK®.\" On the right, a tablet and phone display medical images.")

October 2026 Question  
**CHEST SEEK® Challenge: What is the most likely diagnosis?**

A 51-year-old woman presents for evaluation of cough, difficulty with swallowing solid foods, and unintentional weight loss for the past 3 months. A chest radiograph suggests a left lung lesion (Figure 1), with CT imaging confirming a large mediastinal mass with regions of low attenuation, encasing the esophagus and displacing the descending thoracic aorta to the right (Figures 2 and 3). 

![Figure 1. Chest radiograph.](https://info.chestnet.org/hs-fs/hubfs/SEEK/2026-10_SEEK%20Challenge/Figure%201.%20Chest%20radiograph..png?width=353&height=229&name=Figure%201.%20Chest%20radiograph..png)

Figure 1. Chest radiograph.

![Figure 2. Chest CT scan, coronal view.](https://info.chestnet.org/hs-fs/hubfs/SEEK/2026-10_SEEK%20Challenge/Figure%202.%20Chest%20CT%20scan%2c%20coronal%20view..png?width=501&height=417&name=Figure%202.%20Chest%20CT%20scan%2c%20coronal%20view..png)

Figure 2. Chest CT scan, coronal view.

![Figure 3. Chest CT scan.](https://info.chestnet.org/hs-fs/hubfs/SEEK/2026-10_SEEK%20Challenge/Figure%203.%20Chest%20CT%20scan..png?width=801&height=728&name=Figure%203.%20Chest%20CT%20scan..png)

Figure 3. Chest CT scan.

 

 

 

This question is found in the [CHEST SEEK Library](https://www.chestnet.org/Store/Products/Standard-Products/Apps/SEEK-Library).

The SEEK Challenge question is updated monthly. Check back in **November** for next month's question.

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