Unveiling the Unseen: A Rare Case of Primary Pulmonary Lymphoma.

Primary pulmonary lymphoma (PPL) is an uncommon condition involving the lungs, characterized by the abnormal clonal growth of lymphoid cells. Patients with PPL can be asymptomatic or present with vague clinical signs such as cough, fever, chest discomfort, and shortness of breath. Some may also have underlying immunosuppression or autoimmune conditions. Tuberculosis being more common with a higher incidence in endemic areas, PPL can often be misdiagnosed as tuberculosis. Also, they share common symptoms like cough, fever, fatigue, unexplained weight loss, and an upper lobe predilection. Therefore, diagnosing PPL from other common pulmonary diseases is of utmost importance in early diagnosis and treatment. Generally, small biopsy samples are essential for precise diagnosis and prompt treatment. Therapeutic options include chemotherapy, radiotherapy, immunotherapy, and surgical intervention. Herewith we outline a case initially presented as acanthosis nigricans, referred with respiratory symptoms, pleural effusion, and mediastinal lymphadenopathy, which was primarily thought to be a tuberculous pleural effusion. Apart from clinicoradiological and laboratory analysis, thoracoscopy-guided biopsy and histopathological examination pointed toward further steps in diagnosis. The patient was initiated on chemotherapy with an R-CHOP regimen. This case depicts the call for a multidisciplinary perspective for the definite and expeditious diagnosis and management of a paraneoplastic syndrome associated with diffuse large B cell lymphoma. This discussion also highlights the need for a thorough evaluation of paraneoplastic syndromes, as they are crucial in the early diagnosis of the disease and in identifying relapses.