[Pancoast's syndrome: difficulties in its diagnosis]

We present four patients with pancoast tumor diagnosed between 6 to 13 months after the appearance of symptoms. In three of the patients, the presence of old pulmonary apical fibrous lesions complicated diagnosis by simple radiology. Clinical suspicion of the tumor provided the basis for further complementary explorations which confirmed the apical lesion: TC in two patients and RM in the third. Three patients histological diagnosis was obtained by aspirative transthoracic punction. The late diagnosis resulted in the treatment being purely palliative in three cases. It should be stressed that when presented with persistent shoulder pain, clinicoradiological assessment need to be exhaustive in order to make an early diagnosis.