Reddish-blue nodules were found on the tips of some of the toes of a 62-year-old woman. These nodules were painful when pressure was applied The clinical appearance of the efflorescence was most similar to that of glomangiomas. In addition, a lesion was observed on her lip that was suspected of being a lymphoma. The histological and immunohistological findings for all the lesions were consistent with the diagnosis of a non-Hodgkin lymphoma of low-grade malignancy. Consequently, a detailed internal medical examination was performed: biopsy specimens of the gastrointestinal mucosa revealed the presence of an immunocytoma. The significance of the immunohistological differentiation of lymphocyte subclasses by monoclonal antibodies for the diagnosis of lymphoma is demonstrated.