Cough and melena in a 60-year-old man

A 60-year-old man came to the outpatient department with complaints of cough for 3 months. He was apparently well 3 months ago when he noticed a dry cough. It was initially quite occasional but since the past 1 month it has become more persistent and is present throughout the day. In the past 15 days, he has also noticed a chest pain which is bilateral and present in the interscapular and infrascapular regions. It is a dull pain which disturbs his sleep. On further inquiry, the patient said that he was a non-smoker and had worked as a clerk in an office, for 35 years. His appetite had reduced and he had lost about 15kg of weight in the past 4 months. There was no history of tuberculosis in the past nor did he have recent contact with a tuberculosis patient. He however added, that since the past 6 months he had noticed that his stools were darkcoloured and he now frequently suffered from constipation occasionally alternating with diarrhoea. Micturition was normal. On examination, the patient was underweight. He was afebrile and his vital parameters were normal. His chest examination revealed only a few scattered rhonchi bilaterally over the chest. No bronchial breath sounds, rales or other adventitious sounds were heard. On abdominal examination, liver and spleen were not palpable and there was no guarding or rigidity. However, there was mild tenderness on palpation in the left paraumbilical region laterally. No abdominal masses were felt. Rest of the clinical examination was normal. (copied from article)