LINITIS plastica type of carcinoma is an interesting entity, not only from the clinical point of view but from the standpoint of pathologic diagnosis as well. Clinically it is practically never recognized as carcinoma since it tends to mimic certain other diseases, such as ulcerative colitis, or it may elude diagnosis completely. Anatomically it is a diffusely infiltrating carcinoma comparable to a phlegmonous inflammation. Coincident with the spread of tumor cells there is subacute and chronic inflammation, with much new formation of connective tissue. The primary carcinoma, obviously an anaplastic mucin-secreting adenocarcinoma, rapidly infiltrates the surrounding tissues, especially the submucosa and muscularis, leaving only shallow ulcerations in its wake. Because of the fast spread of the inflammatory lesion and of the individual cancer cells, large portions of the stricken organ are often involved. Though the lesion is originally an adenocarcinoma, many of the infiltrating cells form only abortive glandular structures