Esophageal blue nevus: An isolated endoscopic finding

Esophageal melanosis: Two case reports and review of literature

BACKGROUND

Esophageal melanosis (EM) is a rare condition characterized by melanin pigmentation in the esophageal mucosa. It is not well understood and has been documented in less than 100 cases worldwide.

CASE SUMMARY

We report two cases of African American patients who complained of significant weight loss (over 20 pounds in approximately six months) and abdominal pain during their first visit. The first case involves a 54-year female with a history of hepatic steatosis and polysubstance abuse, who also experiences nausea and vomiting. The second case is a 59-year-old male with hypertension and gastroesophageal reflux disease (GERD), who was diagnosed with esophageal squamous cell carcinoma. Both cases show benign melanocytes in the basal layer on the esophagus biopsy and are diagnosed as EM.

CONCLUSION

It is important to note that EM has been associated with malignancies such as carcinoma and melanoma. Therefore, accurate diagnosis and appropriate management are crucial. Patients with EM, especially those with concurrent risk factors (e.g., GERD, smoking), should be carefully monitored for any signs of malignancy.

Melanoma arising in extracutaneous cellular blue nevus: report of two cases with comparison to cutaneous counterparts and uveal melanoma

AIMS

Blue nevi are benign melanocytic lesions that typically occur in the dermis. Melanoma arising in blue nevus is rare and shows a molecular profile distinct from conventional forms of cutaneous melanoma and more similar to uveal melanoma and central nervous system (CNS) melanocytomas. In contrast to conventional cutaneous melanoma, these tumor types typically show activating driver mutations in GNAQ or GNA11, a low mutational burden without evidence of a UV signature, and a reproducible pattern of chromosomal copy number changes. Blue nevi can also occur at extracutaneous sites. Here we report two cases of melanoma arising in extracutaneous blue nevus and compare their molecular features to cohorts of melanoma arising in cutaneous blue nevus (5 patients) and uveal melanoma (6 patients).

METHODS AND RESULTS

We describe the clinical, histomorphologic, immunohistochemical, and molecular findings in these two cases of melanoma arising in extracutaneous blue nevus. We compare their molecular profiles to melanomas arising in cutaneous blue nevus and uveal melanoma using a targeted next-generation DNA sequencing platform and find striking similarities between all three groups.

CONCLUSIONS

The close relationship between blue nevus-associated melanomas, regardless of their anatomic site, supports and validates the concept of melanoma arising in extracutaneous blue nevus and suggests that the two groups share common pathogenic mechanisms. The similarity of both groups to uveal melanoma in turn supports the close relationship between blue nevus-associated melanoma, uveal melanoma, and CNS melanocytoma, and their distinction from conventional UV-associated melanoma. These findings have important implications for prognosis and therapy.

Esophageal Melanocytosis: report of two cases and review of a rare and misunderstood entity

Esophageal melanocytosis (EM) is a rare entity, which is characterized by a non-atypical melanocytic proliferation and melanin deposits in the esophageal mucosa. The confusion between the terms of melanosis and melanocytosis in the literature, the rarity of this lesion (less than 50 cases reported in the literature), its uncertain pathobiological course and the lack of experience of pathologists and gastroenterologists prompt us to draw the attention to this particular entity by reporting two cases and reviewing the literature. Magnifying endoscopy to observe intensive melanin accumulation followed by a biopsy are key for the diagnosis.

Large Plaque-type Blue Nevus with GNAQ Q209P Mutation, Involving Mammary Gland Tissue: Under-Recognized Mammary Condition as an Origin of Primary Mammary Melanocytic Tumors

ABSTRACT

Plaque-type blue nevus is a rare variant of blue nevi that was first described in 1954. This article presents clinical, macroscopic, histopathological, and genetic findings for a case of large plaque-type blue nevus expanding into the mammary gland tissue as well as the skin of the right breast. A 63-year-old woman presented with a congenital, large, blue-colored macule limited to the hypochondriac area of the right breast. A nodule 8 mm in diameter was also present in the mammary gland tissue. Magnetic resonance imaging was unable to detect diffuse melanin deposition in the mammary gland tissue, but pigmentation in the whole mammary parenchyma was observed in the cut surfaces of the mastectomy specimen. Histopathology revealed a sparse distribution of dendritic melanocytes in whole sections of the mammary fibrous tissue and partial sections of the dermis. The histopathological criteria for atypical cellular blue nevus were fulfilled for the mammary tumor. Nodal blue nevus was diagnosed in the sentinel lymph node. Sanger sequencing confirmed the GNAQ Q209P mutation, which was also identified in all 4 literature cases of plaque-type blue nevus, but rarely in conventional blue nevi and uveal melanoma. It should be noted that plaque-type blue nevus can expand into the mammary gland tissue, even if the pigmented lesion does not exist on the overlying breast skin. The mammary condition can be the origin of primary mammary melanocytic tumors. Mosaicism of the GNAQ Q209P mutation can be a characteristic genetic alteration to extensive blue nevi, including plaque-type blue nevus.

Primary intra-abdominal melanoma arising in association with extracutaneous blue naevus: a report of two cases

AIMS

Blue naevi are uncommon dermal melanocytic neoplasms characterised by GNAQ/GNA11 mutations, which very rarely progress to melanoma. Such melanomas also often have BAP1 mutations, and lack genetic events associated with conventional melanoma. Exceptionally, blue naevi arise in extracutaneous locations; one melanoma arising in this setting has been reported. We report the clinicopathological, immunohistochemical and molecular genetic features of two cases of melanoma arising in extracutaneous blue naevus.

METHODS AND RESULTS

Both arose in males, aged 25 and 63 years, with no history of other melanocytic lesions, and presented as large, painful intra-abdominal masses. The tumours were dark-brown/black, multilobulated, involved small intestinal mesentery and consisted of a predominantly fascicular and spindled, but occasionally nested and epithelioid, proliferation of variably pigmented, relatively monotonous cells with pale cytoplasm and ovoid nuclei with mild to moderate atypia. Mitotic activity was variable but generally low. Both cases showed areas of conventional and cellular blue naevus. Recurrent tumour in one case showed predominantly epithelioid morphology and greater cytological atypia and mitotic activity. One case expressed Melan-A, SOX10 and CD117, with absent expression of S100 protein and DOG1; the other expressed Melan-A, HMB45 and S100 protein. Next-generation sequencing identified GNAQ and BAP1 mutations in one case and GNA11 mutation in the other. Both patients developed widespread metastatic disease.

CONCLUSION

Exceptionally rare, aggressive melanomas arising in extracutaneous blue naevi should be distinguished from metastatic melanoma, gastrointestinal stromal tumour and malignant melanotic nerve sheath tumour, especially given the significant therapeutic and prognostic differences between these different entities.

Clinicopathological study of blue nevi of the gastrointestinal (GI) tract: first case series

AIM

Blue nevus (BN) is a benign melanocytic proliferation that is typically cutaneous. Extracutaneous BN is infrequent and is reported in the mucosa of various organs. Gastrointestinal (GI) tract BN is rare. Here, we describe the clinicopathological findings of the largest series of GI tract BNs.

METHODS

A search of our Pathology Data System (1984-2019) identified six GI tract blue nevi. Clinical information, pathology reports and available H&E-stained section slides were reviewed.

RESULTS

Lesions predominated in the middle-aged adults (mean 54, range 27-80) with a slight female predominance (66%). Most cases arose in the rectum and colon (83%), with one gastric lesion (17%). Four cases were identified during endoscopic examination performed either for screening or for unrelated symptoms (66%). Two patients presented with rectal bleeding (33%) unassociated with the BN. Endoscopically, most lesions appeared as superficial hyperpigmented areas (83%). One case was described as abnormal mucosa (17%). Microscopically, the mucosa was involved in all of the cases (100%). One case showed submucosal extension in addition to the mucosal component (17%). Lesions showed a proliferation of bland spindle cells with abundant granular pigment. No nuclear atypia or mitoses were identified. Immunostains showed immunoreactivity for melanocytic markers. Follow-up information available for five patients showed no recurrences to date (mean follow-up 1 year).

CONCLUSIONS

BN is a benign melanocytic proliferation. It is important to be aware of the occurrence of such lesions outside of the skin and consider the possibility of BN when pigmented lesions are encountered in the GI tract.

Blue Nevi of the Ocular Surface: Clinical Characteristics, Pathologic Features, and Clinical Course

PURPOSE

Blue nevus is a melanocytic tumor that is commonly found in the skin. Extracutaneous presentations, including the ocular surface, are rare. As such, the purpose of this study was to characterize the clinical features and clinical course of congenital melanocytic tumor (blue nevus) of the conjunctiva.

DESIGN

Retrospective, noncomparative case series.

PARTICIPANTS

Twenty-one patients with 23 blue nevi of the ocular surface that were excised surgically between 2000 and 2016.

METHODS

Chart review of patients identified from a database search of the Florida Lions Ocular Pathology Laboratory records. Pathologic diagnoses were confirmed by 2 pathologists (S.R.D. and G.E.). All specimens were bleached and, tissue permitting, stained using SOX10 (MilliporeSigma, Darmstadt, Germany) and CD68 (Leica Biosystems, Nussloch, Germany).

MAIN OUTCOME MEASURES

Clinical characteristics, pathologic features, and clinical course.

RESULTS

Mean age of the population was 55±15 years; 71.4% (n = 15) were white and 57.1% (n = 12) were men. One patient had 3 lesions, for a total of 23 lesions examined. Clinically, 13 lesions were on the bulbar conjunctiva, 3 were on the tarsal conjunctiva, 3 were in the fornix, 2 were caruncular, 1 was episcleral, and 1 was at the limbus. Before excision, 8 patients were thought to have primary acquired melanosis, 4 with concern for primary conjunctival melanoma, and 1 thought to have metastatic disease from a plantar melanoma. Five lesions were thought to be benign, and in 8 patients, the lesions were identified incidentally after other ocular surgeries, with no diagnosis of the lesions before excision. Pathologic features were consistent with simple blue nevi in 21 lesions and cellular blue nevus in 2 lesions. No malignant transformations were noted in any patient over the mean 20.2-month follow-up period (range, 2 weeks-103 months).

CONCLUSIONS

Blue nevus is a rare deeply pigmented congenital melanocytic lesion with a benign clinical course that can appear clinically similar to primary acquired melanosis or melanoma.

An unusual localization; esophageal melanocytosis

Esophageal melanocytosis is a rare clinical and pathological condition characterized by non-atypical melanocytic proliferation and increased melanin in the esophageal mucosa, which is normally histologically non-melanocytic. Intensive melanin accumulation and hyperpigmentation are necessary for endoscopic recognition. Due to the fact that it is a rare gastrointestinal system pathology, experience and knowledge about its diagnosis, treatment and course are also limited. Although it is argued that chronic stimulating factors have an influence, there is no clear information about its etiology and pathogenesis. Malignant melanomas and melanocytic nevus in particular come to the fore in the differential diagnosis. Opinions and findings indicating that melanocytosis may be a precursor for malignant melanoma make the recognition and follow-up of this clinical and pathological entity more important. In this article, a patient with esophageal melanocytosis diagnosed by endoscopic evaluation is presented, with the aim of increasing the awareness of clinicians, especially endoscopists and pathologists, on this subject.

A Rare Disease of the Digestive Tract: Esophageal Melanosis

Esophageal melanosis which is characterized by melanocytic proliferation in the squamous epithelium of the esophagus and melanin accumulatin of esophageal mucosa (EM) is a rare disease of the digestive system. Although esophageal melanosis is considered to be a benign disease, its etiology is not cleared and has been reported to be the precursor lesion of esophageal primary melanomas. In this report, we aimed to note esophageal melanosis in a 55-year-old female case who applied to our clinic with difficulty in swallowing, burning behind the breastbone in the stomach, heartburn, indigestion, and pain in the upper abdomen after endoscopic and pathologic evaluation. Complaints dropped with anti-acid therapy and case was followed by intermittent endoscopic procedures because of precursor melanocytic lesions.

Blue nevi and related lesions: a review highlighting atypical and newly described variants, distinguishing features and diagnostic pitfalls

Blue nevi and related entities are a heterogenous group of congenital and acquired melanocytic tumors that includes established entities such as dendritic ("common") blue nevus and cellular blue nevus, and their numerous clinical and pathologic variants, such as deep penetrating nevus. They share several clinical and morphologic features including their blue tinctorial properties, the presence of a dermal proliferation of spindle, fusiform or ovoid cells, associated melanin pigment (both within the melanocytic tumor cells and also within macrophages) and stromal sclerosis and, at least focal positivity for HMB-45 (Gp100). Some variants, such as deep penetrating nevus, often show considerable variation in nuclear size and shape, and, as a consequence, are at risk of being misdiagnosed as melanoma by those unfamiliar with their characteristic morphologic features. The so-called malignant blue nevus is a controversial term denoting melanomas arising in association with or exhibiting some morphologic similarities to blue nevus. There are also lesions that are probably related to blue nevi, such as the recently described pigmented epithelioid melanocytoma and the neurocristic hamartomas, whose nature, biologic behavior, and relationship to the better established entities remains to be clearly established. This review aims to present a brief overview of these lesions, highlighting their pathologic characteristics, distinguishing features and potential diagnostic pitfalls, with particular emphasis on recently described entities, molecular findings, controversial areas, and approaches to diagnosis.

Esophageal melanocytosis morphologic features and review of the literature

Endoscopic or macroscopic esophageal melanocytosis is a benign clinicopathologic entity characterized by melanocytic proliferation in esophageal squamous epithelium and melanin deposition in the mucosa. Little is known about the etiology and natural course of this condition, although it has been suggested to be a precursor of primary esophageal melanoma by some authors. Following a search of the bibliographic databases (PubMed and Medline) regarding esophageal melanocytosis and melanosis, thirty-four cases of isolated esophageal melanocytosis (including one unpublished case from us) were found. The histopathologic features of esophageal melanocytosis are reviewed and its differential diagnosis with other pigmented esophageal lesions is discussed.