A 35 years old male, with pre-morbid anxious traits & heavy smoker, believes that he has been suffering from 'lung carcinoma' for a year, No significant clinical finding is detected on examination and relevant investigation. He continues to stick to his belief despite evidence to the contrary. In the process, he has spent a huge amount of money, time and energy in getting himself unduly investigated. He is most likely suffering from:

B. i.e. Hypochondrical disorderThis is a case of Hypochondriasis.Since the patient has himself made the diagnosis of lung carcinoma and is fixed on his belief despite the examination and investigation. The person is suffering from psychiatric disorder --> Lung carcinoma is ruled out.In Malingering: The fabrication derives from a desire for some external reward. Always conscious motive. Nothing of this so present in question Malingering is ruled outSomatic delusional disorders are three types:Delusion of infestation including parasitosisDelusion of dysmorphia such as personal ugliness or exaggerated size of body pasDelusion of foul body odour or Halitosis So in case of delusion, the patient definitely believes that he is suffering from some disease but the nature of the disease is generally not very serious Delusion is ruled outDiagnostic Criteria of Hypochondriasis:a) Patient is preoccupied with fear or belief of having serious disease based on person's own interpretation of normal body function or minor physical abnormalityb) Fear or belief is not a delusion & patient may agree regarding the possibility of his exaggeration of disease a) Belief persist even after showing normal repos.