Small cell carcinoma of the lung is one of the less common types of lung cancer, characterized by aggressiveness, frequent relapses to chemotherapy, and a poor overall survival, particularly when diagnosed in advanced stages. The clinical presentation encompasses cough, hemoptysis, chest pain, and systemic signs of weight loss and fatigue in patients who reached the later stages of the disease. The diagnosis is made through a detailed clinical assessment, imaging studies, and a histopathological examination via bronchoscopy or transthoracic needle aspiration.
Small cell carcinoma of the lung (SCLC) comprises approximately 15% of all lung cancer patients and is recognized as a very aggressive form of malignancy [1] [2]. The clinical presentation of patients with lung cancer is centered around respiratory symptoms, but depending on the stage, various systemic signs are observed [1] [3] [4]. Although the diagnosis might be made incidentally, the vast majority of patients experience some symptoms when the disease is recognized [1] [3]. Studies have established a different frequency of symptoms depending on the location of tumor growth [3] [4]. Cough is the most common symptom when the tumor is localized in the bronchi, as are hemoptysis and dyspnea [3] [4]. Stridor and wheezing are less frequent in the initial stages [3] [4]. When intrathoracic spread has occurred, chest pain develops in up to 49% of patients and is often accompanied by pleural/pericardial effusions, dysphagia, Horner's syndrome (ptosis, miosis, anhidrosis), and hoarseness [3] [4]. In the most advanced stages where metastatic spread is evident, systemic findings of weight loss, fever, night sweats, and fatigue are reported, together with headaches, paraplegia, and bone pain [3] [4]. Several paraneoplastic syndromes are well-known to occur in small cell carcinoma of the lung and other types of lung cancer, including Lambert-Eaton myasthenic syndrome (LEMS), syndrome of inappropriate antidiuretic hormone secretion (SIADH), etc [3] [4]. Small cell lung carcinoma is strongly linked with cigarette smoking [1].
Even if the diagnosis of small cell carcinoma of the lung is made early on, it carries a very poor prognosis [1] [5]. Nevertheless, an early diagnosis will undoubtedly prolong the patient's life and provide an opportunity for more efficient treatment. The first step in the diagnostic workup is a thorough patient history that will cover the onset of symptoms and their progression, followed by auscultation of the lungs and a detailed physical examination. If evident suspicion is raised, imaging studies must be used. Although plain radiography might be useful as a first-line study, computed tomography is recommended [3]. In addition to the lungs, the head, the abdomen, and the extremities should be assessed in order to determine the stage of the tumor [1] [3]. To confirm the diagnosis of a small cell carcinoma of the lung, a sample is needed for histopathological examination [1] [3] [4] [6]. Bronchoscopy and transthoracic needle aspiration (TTNA, which may be guided by ultrasound or CT if necessary) are the two procedures that can obtain a viable sample for testing and subsequent determination of the exact tumor type [3] [4] [6]. TTNA, however, is more prone to inducing pneumothorax compared to standard bronchoscopy [6].