The association of various pathologic changes in the lung, especially interstitial fibrosis, in progressive systemic sclerosis is a recognized occurrence. Usually it is not the site of development of a malignancy. As a corollary the literature contains a number of examples of carcinoma developing in the lung in patients with idiopathic basilar fibrosis unrelated to PSS. Currently, we have reviewed the available literature and found a satisfactory description of 44 cases of carcinoma of the lung in patients with progressive systemic sclerosis. Also, there are brief descriptions of 10 cases of pulmonary carcinoma and PSS. The development of a malignancy superimposed upon the chronic changes in the lung, associated with the systemic sclerosing process may be related pathogenically to an altered immunologic response.