Considerable interest in the pemphigoid dermatoses has arisen since Lever1 demonstrated that these disorders can be differentiated from true pemphigus by the lack of acantholysis in the former and its presence in the latter. It is often difficult, if not impossible, to distinguish among the nonacantholytic bullous diseases which resemble pemphigus vulgaris clinically (dermatitis herpetiformis, erythema multiforme, and bullous pemphigoid). Diagnosis, therefore, is often made on the basis of clinical course, response to therapy, or predominance of a particular feature of one disease.
Eruptions which fall into this group have been reported occasionally in connection with various internal malignancies. The pathogenesis has been thought to be an illdefined toxic effect of the neoplasm, the lesions usually developing after the appearance of the neoplasm. Cancer of the stomach and metastatic adenocarcinoma of the adrenals or lung have been associated with erythema