Primary gastric melanoma: case report of a rare malignancy

A rare gastrointestinal tumor: primary gastric melanoma

Primary gastric melanoma is an exceptional tumour with less than 20 cases described in the literature, as its origin is not entirely clear as the presence of melanocytes in the stomach has not been demonstrated. Symptomatology is non-specific, which prevents its early detection, and it is diagnosed in late stages. We present the case of a patient who was admitted to our hospital for vomiting in coffee grounds with analytical and haemodynamic repercussions. Urgent gastroscopy revealed a gastric lesion suspicious for malignancy, which was histologically confirmed as gastric melanoma. The therapeutic approach to these tumours is complex and they have a very poor prognosis.

Interaction between Age and Primary Site on Survival Outcomes in Primary GI Melanoma over the Past Decade

BACKGROUND

Primary malignant melanomas of the Gastrointestinal mucosa are uncommon. Most cases of gastrointestinal (GI) melanomas are secondary, arising from metastasis at distant sites. The purpose of this study is to assess to what extent the interaction between independent prognostic factors (age and tumor site) of primary GI melanoma influence survival. Furthermore, we also aimed to investigate the clinical characteristics, survival outcomes, and independent prognostic factors of patients with primary GI melanoma in the past decade.

METHODS

A total of 399 patients diagnosed with primary GI melanoma, between 2008 and 2017, were enrolled in our study by retrieving data from the Surveillance, Epidemiology, and End Results (SEER) database. We analyzed demographics, clinical characteristics, and overall mortality (OM) as well as cancer-specific mortality (CSM) of primary GI melanoma. Variables with a p value < 0.1 in the univariate Cox regression were incorporated into the multivariate Cox model (model 1) to determine the independent prognostic factors, with a hazard ratio (HR) of greater than 1 representing adverse prognostic factors. Furthermore, we analyzed the effect of the interaction between age and primary location on mortality (model 2).

RESULTS

Multivariate cox proportional hazard regression analyses revealed higher OM in age group 80+ (HR = 5.653, 95% CI 2.212-14.445, p = 0), stomach location of the tumor (HR = 2.821, 95% CI 1.265-6.292, p = 0.011), regional lymph node involvement only (HR = 1.664, 95% CI 1.051-2.635, p < 0.05), regional involvement by both direct extension and lymph node involvement (HR = 1.755, 95% CI 1.047-2.943, p < 0.05) and distant metastases (HR = 4.491, 95% CI 3.115-6.476, p = 0), whereas the lowest OM was observed in patients with small intestine melanoma (HR = 0.383, 95% CI 0.173-0.846, p < 0.05). Multivariate cox proportional hazard regression analyses of CSM also revealed higher mortality of the same groups and lower CSM in small intestine and colon melanoma excluding the rectum. For model 2, considering the interaction between age and primary site on mortality, higher OM was found in age group 80+, followed by age group 40-59 then age group 60-79, regional lymph node involvement only, regional involvement by both direct extension and lymph node involvement and distant metastases. The small intestine had a lower OM. The rectum as primary location and the age range 40-59 interacted to lower the OM (HR = 0.14, 95% CI 0.02-0.89, p = 0.038). Age and primary gastric location did not interact to affect the OM. For the CSM, taking into account the interaction between age and the primary location, higher mortality was found in the same groups and the colon location. The primary colon location also interacted with the age group 40-59 to increase the CSM (HR = 1.38 × 10⁹, 95% CI 7.80 × 10⁷-2.45 × 10¹⁰, p = 0).

CONCLUSIONS

In this United States population-based retrospective cohort study using the SEER database, we found that only the age range 40-59 interacted with the rectum and colon to lower and increase mortality respectively. Primary gastric location, which was the single most important location to affect mortality, did not interact with any age range to influence mortality. With those results, we hope to shed some light on this rare pathology with a very dismal prognosis.

Metastatic primary gastric melanoma: a rare clinical presentation and a review of literature

Primary gastric melanoma is a rare clinical finding. It presents with upper gastrointestinal symptoms like abdominal pain, weight loss and melaena. It is often difficult to differentiate a primary gastric melanoma from primary cutaneous melanoma with gastric metastasis. Upper gastrointestinal endoscopy and biopsy of the lesion for histopathology and immunohistochemistry help to reach a definite diagnosis. We report a case of primary gastric melanoma with metastases to the liver and bone. The patient was treated with palliative radiotherapy, palliative chemotherapy and a bone-stabilising agent.

Oral malignant melanoma with gastric metastasis and hemorrhage: A case report

BACKGROUND

Although the gastrointestinal tract is a relatively common site of melanoma metastases, reports of digestive tract hemorrhage caused by melanoma are very rare. The metastatic route is still unclear, though it is considered as implant metastasis in oral malignant melanoma.

CASE SUMMARY

We report the case of an 88-year-old man who was admitted to our hospital with hematemesis and melena. By endoscopic inspection, he was diagnosed with active hemorrhage caused by primary gastric cancer or gastric stromal tumor. Eventually, he underwent surgical resection treatment and was discharged. At the outpatient review 3 wk postoperatively, it was noted that an oral melanoma which had been overlooked preoperatively had enlarged several times and was eventually considered to be the primary focus of the gastrointestinal melanoma. The patient passed away at home after 1 mo.

CONCLUSION

In the present case, an oral cavity mass was found but not further identified, which caused misdiagnosis. The possibility of malignant melanoma should be considered when encountering a gastrointestinal mass, especially when combined with mucocutaneous melanoma. In patients who have pure cutaneous melanoma, attention should also be paid to their gastrointestinal symptoms, with regular gastrointestinal endoscopy or systemic examination performed.

Primary Gastric Malignant Melanoma in a 68-Year-Old Woman: A Case Report and Review of the Literature

Non-cutaneous melanoma is a very rare clinical entity. Gastric melanoma can be primary or secondary, but determining their nature is in most cases very challenging. To date, very few cases of primary gastric melanoma have been described in the literature. We report the first case of primary gastric melanoma documented in a Romanian patient, confirmed through clinical, imagistic, and pathological diagnosis. A 68-year-old female patient presented to our hospital with complaints of dyspepsia, abdominal pain, and weight loss. Esophagogastroduodenoscopy revealed two large sessile masses in the gastric fundus, which was histologically compatible with melanoma; immunohistochemistry staining was positive for vimentin, S100 protein, HMB45 antibody and Melan A/MART1, and negative for pan-CKAE1/AE3, leukocyte common antigen and DOG1. Extensive dermatological and ophthalmological examinations did not identify a primary lesion. The patient was therefore diagnosed with primary melanoma of the stomach. At the time of the diagnosis, multiple bone and pulmonary metastases were detected and considering the poor general status of the patient, surgery was not recommended. She died three months following diagnosis. A review of the literature identified only 32 other reported cases of primary gastric melanoma, all in individuals ≥50 years of age and most of them in male patients. Partial or total gastrectomy was the usual treatment of choice, but prognosis was overall poor. Awareness of this rare condition must be increased among healthcare providers, as early detection can improve survival chances.

Primary jejunal amelanotic melanoma: case report and review of literature

Intussusception more commonly occurs in pediatrics but is a rare cause of bowel obstruction and gastrointestinal bleeding in adults. It typically occurs in adults due to a malignancy, which serves as a pathologic lead point. We present a case of a 64-year-old female with nausea, vomiting, and melena who was found to have intussusception associated with a primary jejunal amelanotic melanoma. Both intussusception and primary small bowel melanomas are rare causes of obstruction and bleeding. Intussusception occurring as a result of a primary small bowel amelanotic melanoma is exceedingly rare with very few reported cases. We provide a case report and review of the literature.

Primary malignant melanoma of the gastric antrum: A case report

Primary melanoma of the antrum is a rare and aggressive disease. Diagnosis requires a correlation between the patient's history, tumor histopathology, and immunohistochemistry. Surgery and mutation-targeted treatments may improve overall survival.

Primary gastric melanoma in a young woman: A case report

BACKGROUND

Most melanomas identified in the stomach are metastatic. The primary gastric melanoma (PGM) is extremely rare. As such, clinical reports of PGM are scarce in the literature, lending to the challenge of diagnosis and treatment.

CASE SUMMARY

A 31-year-old woman presented with a 1-mo history of dysphagia but no symptoms of abdominal pain, abdominal distension, nausea, vomiting, hematemesis, or melena. The patient reported an unintentional weight loss of 6 kg within that time. History-taking revealed no previous medical conditions or surgical events. Abdominal computed tomography at a local hospital had suggested gastric tumor. Endoscopic examination in our hospital found a large, irregular, black mass. Subsequent laparoscopic exploration found the tumor on the side of the stomach fundus penetrating through the serosa, and enlarged lymph nodes (groups 1, 3, 7, and 9) fused into a mass, surrounding the peripheral artery and inseparable. Postoperative immunohistochemistry suggested gastric malignant melanoma. Positron emission tomography-computed tomography confirmed PGM. Treatment with programmed cell death protein 1 antagonist (toripalimab) plus chemotherapy (paclitaxel) was initiated but discontinued upon tumor bleeding. At the last telephone follow-up, the patient reported poor general condition but was alive.

CONCLUSION

Although unresolved and ongoing, this rare case of PGM expands the overall knowledge about this rare tumor’s diagnosis and management.

Primary Gastric Malignant Melanoma

Primary gastric malignant melanoma (PGMM) is an extremely rare clinical entity, and few cases have been described in the literature. Here, we report a histologically confirmed PGMM case of a 74-year-old man with a mass in the stomach found by gastroscopy. The patient had no history of melanoma. This rare disease may be misdiagnosed for another gastric malignant tumor type when there is no known primary lesion. Early detection and surgical intervention are critical for long term survival or cure, though the tumor is often advanced at the time of diagnosis and is associated with a dismal outcome.

The challenge of primary gastric melanoma: a systematic review

AIM

Primary gastric melanoma is a rare clinical presentation. The purpose of this review was to compare the 1-year survival in patients who underwent surgery with patients who did not receive treatment.

PATIENTS & METHODS

A systematic search of databases for case reports and case series of primary gastric melanoma was conducted.

RESULTS

The mean survival of patients was 22 months. One-year survival was 56.5% with surgery, rising to 66% with adjuvant therapy. Mean survival of the surgical group was 21.05 months (±20.2) versus 4.5 months (±3.61) in the nonsurgical group.

CONCLUSION

Primary gastric melanoma has a poor prognosis but early surgical intervention can have a significant impact on patient outcome. We reviewed the biology and clinical diagnosis of gastrointestinal melanoma and the current management options available.

Primary gastric melanoma in adult population: a systematic review of the literature

BACKGROUND

Primary gastric melanoma (PGM) is a rare malignant tumour of the stomach with poor prognosis. The aim of this systematic review was to assess the available literature on this entity and to highlight its biological behaviour and preferred treatment approach.

METHODS

PubMed and Cochrane bibliographical databases were independently searched (last search: 2 February 2020) by two investigators for articles reporting on PGM in the adult population.

RESULTS

Twenty-five studies met the inclusion criteria and concerned collectively 25 patients (18 males and seven females) with an age of 63.4 ± 8.97 years (mean ± standard deviation). Main symptoms included abdominal pain (64%), weight loss (48%) and hematemesis or melena (32%). The most frequent tumour location was the body of the stomach (54.2%). All tumours were surgically resected and the majority of the patients had a partial gastrectomy (52%). Median recurrence time was 5 months and 12% of patients reached 5-year survival landmark.

CONCLUSION

PGM is a rare disease characterized by an aggressive malignant behaviour. Its differential diagnosis from a metastatic lesion is crucial. A prompt diagnosis and therapeutic approach are needed. Further studies are required to elucidate the optimal management of this clinical entity.

Primary gastric melanoma: A case report with imaging findings and 5-year follow-up

BACKGROUND

Most melanomas identified in the stomach are metastatic; primary gastric melanoma (PGM) is extremely rare, and the relevant studies are relatively scarce. PGM may be incorrectly diagnosed as other gastric malignant tumor types.

CASE SUMMARY

We describe a rare case of PGM confirmed through long-term clinical observation and pathological diagnosis. A 67-year-old woman presented to our hospital with recurrent chest tightness and chest pain. Digital gastrointestinal radiography revealed a circular shadow in the gastric cardia. Computed tomography (CT) revealed a heterogeneous tumor with uneven enhancement. Enlarged lymph nodes were noted in the lesser curvature of the stomach. On magnetic resonance imaging (MRI), T1- and T2-weighted imaging revealed hyperintensity in and hypointensity in the tumor, respectively, both of which increased substantially after uneven enhancement. Near total gastrectomy was performed, and the tumor was pathologically confirmed to be a gastric melanoma. Because no other possible primary site of malignant melanoma was suspected, a clinical diagnosis of PGM was made. The patient was followed for nearly 5 years, during which she received CT reexamination, but no recurrence or metastasis was observed.

CONCLUSION

Certain imaging characteristics could be revealed in PGM. Imaging examination can be of great value in preoperative diagnosis, differential diagnosis, and follow-up of patients with PGM.

Intraepithelial Melanoma in the Stomach After Treatment With Immune Checkpoint Blockade Therapy

Melanoma is the most common tumor to metastasize to the gastrointestinal tract, commonly affecting the small intestine, colon, and anorectum. Primary mucosal melanoma can arise in any gastrointestinal site, most frequently affecting anorectal mucosa. Melanoma involving the gastric mucosa, specifically, is exceedingly rare and carries a poor prognosis with a median survival of 5 months. The presence of atypical melanocytes exclusively within gastric epithelium has not been previously described. We report a case of a 52-year-old man with widespread BRAFV600E mutant metastatic melanoma who was referred to our institution for immune checkpoint antibody-blockade therapy. The patient had previously been treated with BRAF inhibitors, and despite initial response to therapy, developed resistance leading to disease progression and multiorgan involvement including the liver, spleen, and axial skeleton. Immune checkpoint antibody blockade with ipilimumab and pembrolizumab has been shown to induce significant tumor regression in patients with melanoma by upregulating T-cell activity and removing the natural check on the host immune response. After his first dose of combination therapy, the patient underwent an upper gastrointestinal tract endoscopy for severe nausea and was found to have 2 pigmented lesions within the gastric body, one of which was biopsied. The biopsy showed gastric body-fundic type mucosa with melanophages and scattered atypical intraepithelial melanocytes within the lamina propria, which were strongly positive for S100, HMB45, SOX10, and MITF. A Fontana-Masson silver stain was performed for confirmation. The finding of predominantly atypical intraepithelial melanocytes associated with melanin pigment was interpreted as metastatic melanoma to the stomach with some regression in response to immune checkpoint blockade therapy.