We describe a patient with progressive hyperpigmentation of the skin and gastrointestinal
melanosis. The pigmented lesions in the stomach and duodenum served as a diagnostic
sign of recurrent disease, 26 years after excision of melanoma of the skin.
A barium swallow and gastroduodenoscopy were performed in a healthy 63-year-old man
who had been suffering from vague abdominal symptoms for a few months. Multiple flat
and polypoid pigmented lesions, varying from brown to black, were observed in the
stomach and duodenum (Figures [1], [2]). A malignant melanoma had been excised from his neck 26 years previously. The new
biopsies from the pigmented lesions in the upper gastrointestinal tract showed only
melanotic pigment within macrophages and no malignant cells were found. Staining with
S-100 and HMB-45 was negative. On examination, no suspected pigmented nevi were detected
on the skin or mucous membranes. Normal fundoscopy and rectoscopy findings ruled out
the possibility of intraocular or anal melanoma.
Figure 1 The typical “bullseye” in the gastric wall
Figure 2 Brownish appearance of gastric lesion
The results of a computed tomography scan showed diffuse liver metastasis, and some
thickening of the gastric wall at the fundic area. A liver biopsy confirmed the diagnosis
of metastatic malignant melanoma. At 2 months later the patient noticed darkening
of the skin, especially in exposed areas, and voided dark urine. On examination, the
skin and mucous membranes were slate gray, especially on the face, neck, chest and
upper extremities.
The patient died from the disease 7 months after the initial diagnosis.
Malignant melanoma is the most common malignancy to metastasize to the gastrointestinal
tract, involving the small intestine, colon, stomach and esophagus [1]
[2]
[3]. The typical endoscopic finding is the “bullseye” or “target” lesions [1]
[2]. As far as we know, this is the first described case of gastrointestinal melanosis
associated with melanosis cutis, appearing in a patient with ultra-late recurrence
of the disease [4]
[5].
