Gastrointestinal Melanoma: Clinical Study Of 6 Cases And Review Of The Literature

Objective:Malignant melanoma typically occurs on the skin, Gastrointestinal Melanoma(GIM) is extremely rare, and most commonly occur as metastases from the primary site. GIM is easily misdiagnosed because of lacking of special clinical manifestation. Biopsy is essential to conform the diagnosis. Primary Gastrointestinal Melanoma(PGIM) is more likely to occur in the esophagus and anal canal, the prognosis is poor. It is impossible to distinguish whether the tumor was primary or metastatic just depend on pathology, it should be combined with patients'previous history of cutaneous malignant melanoma. This study was designed to discuss the predilection site, clinical, diagnosis, treatment and prognosis of this rare disease, in order to advance the cognition and improve the diagnosis and treatment of GIM.Methods:We collected clinical data of 6 patients with GIM, including general history, medical history, therapeutic history and outcome. All the patients who were treated in the First Affiliated Hospital, Zhejiang University School of Medicine from July 2000 to January 2010.Then we reviewed the related literatures, and retrospectively analyzed the date. Results:Of all 6 patients,5 were male and 1 female, which age from 19 to 54 years old, the average age was 60 years.5 cases was PGIM,1 case was metastatic melanoma of the stomach. Of all 5 cases of primary melanoma, the lesion were respectively located in the esophagus(2 cases), the anal canal(2 cases), and the rectum(1 cases). Both 2 cases of Esophageal melanoma complained dysphagia, and both anal melanoma consulted by hematochezia, the rectal melanoma presenting with pencil-thin stool. The patient with gastric melanoma who complained vague epigastric pain and discomfort had a history of malignant melanoma of the left preauricular skin 8 years previously, therefore the gastric melanoma was determined to be metastatic.An upper gastrointestinal endoscopy showed a black polypoid lesion in the esophagus of the 2. patients with Esophageal melanoma. Endoscopic showed a black polypoid mass in the 2 cases of anal melanoma and an ulceration without obvious pigmentation in the rectal melanoma. As to the patient with gastric metastatic melanoma,Gastroscopy demonstrated an ulcer at the gastric angle.Of all the 6 cases, biopsy were diagnosed as melanoma. One patient with tumor located in the esophagus who was received surgical intervention followed-up for 2 years and was alive, the nonoperative case died within 6 months. The patient with tumor located in the rectal symptoms relieved after surgery and died 1 year later.1 cases with tumor located in the anal received surgical intervention was alive during the 2-year's followed-up, the other one who underwent bio-chemotherapy died within 6 months. The patient with gastric metastatic melanoma underwent a palliative subtotal gastrectomy and followed by large dose interferon (IFNα-2b) adjuvant immune therapy was followed up for 1 year and was still alive.Conclusions:GIM is an exceedingly rare entity, clinical symptoms are similar to other gastrointestinal tumors, the esophagus and anal canal are the most common sites for PGIM, the lesions were polypoid or ulcerative with or without pigmentation. Biopsy was essential to conform the diagnosis. The combination of surgical resection and post operative IFNα-2b adjuvant immune therapy is useful for relief of symptoms and to prolong the disease-free period in patients with GIM.