Anaplastic Lymphoma Kinase (ALK)-Negative Anaplastic Large Cell Non-Hodgkin Lymphoma as a Rare Differential Diagnosis of Lung Cancer: A Case Report.

Anaplastic large cell lymphomas (ALCL) are a group of sporadic malignancies that generally have an aggressive clinical course, especially the subtype of anaplastic lymphoma kinase (ALK)-negative ALCL. The appropriate diagnostic study modalities must be chosen to make an accurate diagnosis and promptly initiate specific treatment. We present the clinical case of a 72-year-old male patient with dyspnea on small efforts accompanied by diaphoresis and a weight loss of 10 kg in two months. Physical examination revealed adenopathy in the cervical region and bilateral pleural effusion. The pleural and lung biopsies revealed poorly differentiated metastatic adenocarcinomas. A multidisciplinary analysis was carried out; the typical clinical-radiographic presentation of adenocarcinoma was ruled out with immunohistochemistry, thus determining a diagnosis of ALK-negative anaplastic large cell non-Hodgkin's lymphoma. This case represented a diagnostic and therapeutic challenge since it is a rare entity with a poor prognosis, and there are only a few studies about the choice of appropriate chemotherapy in these patients.

Obesity hypoventilation syndrome, literature review.

Obesity is a global health concern that has been increasing over the years, and it is associated with several pathophysiological changes affecting the respiratory system, including alveolar hypoventilation. Obesity hypoventilation syndrome (OHS) is one of the six subtypes of sleep-hypoventilation disorders. It is defined as the presence of obesity, chronic alveolar hypoventilation leading to daytime hypercapnia and hypoxia, and sleep-disordered breathing. The existence of a sleep disorder is one of the characteristics that patients with OHS present. Among them, 90% of patients have obstructive sleep apnea (OSA), and the remaining 10% of patients with OHS have non-obstructive sleep hypoventilation without OSA or with mild OSA. This review aims to provide a comprehensive understanding of the epidemiological and pathophysiological impact of OHS and to highlight its clinical features, prognosis, and severity, as well as the available treatment options.