Probable Reactivation of Latent Pulmonary Tuberculosis in A Patient Undergoing Laryngeal Cancer Treatment

Abstract

Background: Tuberculosis (TB) is a highly infectious airborne disease that could develop / be reactivated in a patient with malignancy as an opportunistic infection due to immunosuppression from the malignancy. Thus, tuberculosis should be ruled out in such high-risk conditions in TB–endemic regions such as Nigeria. Immunosuppression either due to cancer or cancer chemotherapy, poses tuberculosis diagnostic and management challenges with atypical clinical presentation, high chance of false-negative results and subsequent delayed diagnosis due to reduction of the sensitivity of molecular diagnostic tests. A high sense of suspicion and repeated or periodic testing is thus needed for prompt diagnosis. Similarly, laryngeal tuberculosis may be considered a differential diagnosis for laryngeal cancer because both conditions can present with similar clinical features such as hoarseness, weight loss, dysphagia, and chronic cough. Case Presentation: A 59-year-old man diagnosed with stage IV laryngeal cancer who had an over 30 years history of tobacco smoking. Initial presentations were progressive hoarseness, dysphagia, suppurating anterior neck swelling but later developed breathlessness which was relieved by tracheostomy. Baseline chest radiography and initial GeneXpert MTB/RIF testing showed no evidence of tuberculosis, and a report of the histology of the neck mass confirmed the mass to be a well differentiated squamous cell carcinoma of the larynx. Following the confirmation from the cell histology; he was commenced on chemotherapy (Cisplatin, Docetaxel and 5- Fluorouracil regimen) and then discharged with retained tracheostomy. Two weeks after the second course of chemotherapy, he developed worsening respiratory symptoms — haemoptysis, copious trachea secretion, fever and progressive weight loss. Repeat chest imaging revealed cavitary lung disease, and GeneXpert testing of tracheostomy secretion confirmed pulmonary tuberculosis. Anti-tuberculosis therapy was initiated, and early clinical improvements were noted leading to subsequent discharge to recommence chemotherapy after completing the intensive phase of anti-tuberculosis medications. Conclusion This case highlights the increased possibility of missing TB diagnosis in cancer patients, thus the need to always rule it out is strongly advocated. The limitation of a single negative GeneXpert result in immunocompromised patients, underscores the importance of repeat testing and radiological reassessment when clinical suspicion persists. Key Clinical Message In TB-endemic settings, pulmonary tuberculosis should remain a key differential diagnosis in oncology patients with persistent or evolving respiratory symptoms. A single negative GeneXpert test alone, without using other diagnostic indices should not be enough to exclude TB in immunocompromised individuals and repeat testing using appropriate respiratory samples may be lifesaving.