Primary Circumscribed Meningeal Melanoma Involving the Meckel's Cave: A Report of a Rare Case and Review of Literature

Primary intracranial meningeal melanomas are rare. Diagnosing primary meningeal melanomas mostly involves comprehensive assessment through clinical and radiological means. This evaluation should encompass a detailed dermal and ophthalmic examination. Any suspicious lesion must be biopsied and examined microscopically. This is crucial not only to differentiate primary intracranial melanoma from other brain tumors but also to rule out metastases from potential sources of primary cutaneous or non-cutaneous melanomas. Surgery is considered the mainstay of treatment. Despite melanomas being generally considered radio- and chemo-resistant tumors, adjuvant radiotherapy and chemotherapy still play a crucial role in their management. The treatment landscape for primary meningeal melanoma is continually evolving, with ongoing research aiming to improve outcomes for patients with this challenging disease.

Multiple aggregated yellow-white globules are a major dermoscopic sign of basal cell carcinoma regardless of their histological subtype

Multiple aggregated yellow-white globules (MAY globules) have been recently described as dermoscopic structures of high specificity associated with high-risk non-pigmented basal cell carcinoma (BCC). To evaluate the diagnostic accuracy of MAY globules in a cohort of pigmented and non-pigmented BCC of all histological types. This was a retrospective case-control study. Dermoscopic and clinical images were all histopathologically confirmed as BCCs of patients seen consecutively at dermatology consultation. Control cases were benign or malignant tumours randomly selected from the database of 8,250 patients. A total of 389 BCCs were included. MAY globules were present in 192 (49%) cases in the BCC group and in only 25 cases in the control group (6,4%). The odds ratio for the diagnosis of BCC was 14.2 (95% CI: 9.62-20.95]). The presence of MAY globules was significant in three histological subtypes, including superficial BCCs. This study shows that MAY globules are a major dermoscopic sign for the diagnosis of BCC, regardless of their histological subtype and their pigmentation.

Pigmented basal cell carcinoma diagnosed in a dental setup: Report of a case with review of the literature

Pigmented basal cell carcinoma is a rare variant of basal cell carcinoma, with only a limited number of reported cases. Because of its similar clinical presentation, it is often over‐diagnosed as malignant melanoma. Along with case presentation, the clinical, microscopic features, and differential diagnosis are discussed in this case report.

Combination of Non-Ablative Fractional Laser with Q-Switched Laser for the Treatment of Becker's Nevus: Efficacy and Limitations

Becker's nevus (BN) is a benign hamartoma that may present as a distressing cosmetic problem. The treatment of BN poses a significant challenge as current therapeutic modalities are suboptimal and have an increased risk of adverse effects, such as scarring and dyspigmentation. We present the use of non-ablative fractional laser therapy combined with Q-switched Nd:YAG laser as a possible therapeutic option for BN treatment and review relevant literature to discuss its efficacy and limitations.

Hyperpigmented mycosis fungoides: a retrospective and comparative analysis with other subtypes of mycosis fungoides

In this study, the clinicopathologic features and survival outcomes of patients with hyperpigmented MF from a single tertiary referral center database were retrospectively evaluated. Hyperpigmented MF accounted for 10.9% (14/128) of all MF cases. The mean age at diagnosis was 46.9 years, and the female-to-male ratio was 1:1.3. Concurrent hypopigmented, ichthyosiform, and poikilodermatous lesions were detected in 21.4%, 14.3%, and 14.3% of the patients, respectively. Histopathologically, most patients (85.7%) showed interface change with pigment incontinence. Double negative (CD4- and CD8-) immunophenotypes were more frequent in patients with hyperpigmented MF (25%) than in those with other MF subtypes (9.8%). Most patients (85.7%) had early-stage disease at diagnosis. The survival outcomes did not differ significantly between hyperpigmented and other MF subtypes. In conclusion, hyperpigmented MF often accompanies other atypical MF variants and is frequently associated with atypical immunophenotypes. The outcomes of hyperpigmented MF are comparable to those of other MF subtypes.

Pigmented apocrine hamartoma: A distinct and uncommon pigmented lesion with dendritic melanocytes and appraisal of terminology

A 20-year-old female presented to a gynecologist with an irregular, darkly pigmented, vulvar lesion. Histopathologic sections of a biopsy specimen showed cystically dilated glands with apical snouts, pigmented secretion, and numerous dendritic melanocytes. The lesion was diagnosed as a pigmented apocrine hamartoma of the vulva. We report the fifth case of this uncommonly encountered entity and discuss the conflicting terminology in the literature of this rare, pigmented lesion.

Basal cell carcinoma: Histopathological gamut

Introduction

Basal cell carcinoma is the most common cutaneous malignancy which is exclusively observed on sun exposed and hair bearing areas of the face.

Diagnosis

We report two rare cases of basal cell carcinoma, which presented as a diagnostic challenge because of rare histopathology.

Findings

Both cases showed pigmentation, while one case resembled adenoid cystic carcinoma because of the glandular and ductal pattern of basaloid cells.

Result

We present these cases because of rare histopathologic presentation.

L3 rootlet recurrent melanocytic schwannoma - case report and literature review

First described by Miller in 1932, melanocytic schwannoma (MS) (melanotic schwannoma, pigmented schwannoma) is a rare variation of peripheral nerve sheet tumours with ectodermal origin occurring predominantly in somatic, but also in the autonomic peripheral system with around two hundred cases in the literature. Predominantly benign tumours, MS are still imaging and pathological challenge and can be easily misdiagnosed with more aggressive peripheral nerve tumours.We report a case of melanocytic schwannoma on L3 sensory rootlet with systematic literature review of nearly 200 cases presented in intracranial, paraspinal region, thoracic, abdominal or pelvic cavities and skin. Two-thirds of cases are part of Carney complex.We present a case of a 61-year-old male with a 3-month history of low back pain, progressive numbness and stiffness in the right thigh, shin and knee, tibial and peroneal paresis causing gait disturbance and neurological claudication. MRI findings present "sand clock" type intradural extramedullary tumour formation with extension to the L3 rootlet through right L3-L4 foramen, hypointense on T2 and hyperintense on T1. Pathological diagnosis of sporadic type melanocytic schwannoma was made via immunohistological and ultrastructural analysis. Thirteen months after total resection there was clinical and MRI evidence of recurrence of the tumour. Total resection and radiosurgery was performed with a recurrence free period of 14 months.A gold standard for melanocytic schwannoma treatment is gross total surgical resection. Despite being considered benign tumours, MS have a local or metastatic recurrence of around 13%. MRI imaging in most of the cases is insufficient and only exhaustive pathological and immunohistological examination is the key to diagnosis. Need of postoperative radiation therapy is still controversial. For the first time, a criterion for postoperative adjuvant therapy was established.

A Transcriptional Analysis of the Genes Involved in the Ascorbic Acid Pathways Based on a Comparison of the Juice and Leaves of Navel and Anthocyanin-Rich Sweet Orange Varieties

Sweet oranges are an important source of ascorbic acid (AsA). In this study, the content of AsA in the juice and leaves of four orange clonal selections, different in terms of maturity time and the presence/absence of anthocyanins, was correlated with the transcription levels of the main genes involved in the biosynthesis, recycling, and degradation pathways. Within each variety, differences in the above pathways and the AsA amount were found between the analysed tissues. Variations were also observed at different stages of fruit development and maturation. At the beginning of fruit development, AsA accumulation was attributable to the synergic action of l-galactose and Myo-inositol, while the l-gulose pathway was predominant between the end of fruit development and the beginning of ripening. In leaves, the l-galactose pathway appeared to play a major role in AsA accumulation, even though higher GalUr isoform expression suggests a synergistic contribution of both pathways in this tissue. In juice, the trend of the AsA content may be related to the decrease in the transcription levels of the GME, GDH, MyoOx, and GalUr12 genes. Newhall was the genotype that accumulated the most AsA. The difference between Newhall and the other varieties seems to be attributable to the GLDH, GalUr12, APX2, and DHAR3 genes.

Pigmented median raphe cyst of the penis that developed after middle age without infection or trauma history

INTRODUCTION

Median raphe cysts are rare benign lesions of the male genitalia that can develop anywhere along the midline from meatus to anus. They are believed to be caused by a defect in closure of median raphe during embryonic development. These cysts commonly appear in childhood or adolescence, although some are diagnosed after middle age, typically triggered by infection or trauma. Pigmented median raphe cysts, or those containing melanin pigment and/or melanocytes, are extremely rare.

CASE PRESENTATION

A 78-year-old man visited our hospital with a complaint of a penile mass that he first noticed in his 50s which slowly grew, eventually causing voiding difficulty. He had no history of infection or trauma. The lesion was excised, and the pathological diagnosis was pigmented median raphe cyst.

CONCLUSION

We successfully treated a rare case of pigmented median raphe cyst of the penis that developed after middle age without infection or trauma history.

Estimating malignancy risk of melanocytic choroidal tumours detected in the Australian National Eye Health Survey

Clinical relevance: The malignant potential of choroidal melanocytic tumours detected incidentally in the community is thought to be low, but this has not been assessed using a validated screening tool. An accurate characterisation of the malignant potential of these lesions has implications for resource allocation, service provision, education, and training.Background: MOLES (Mushroom shape, Orange Pigment, Large size, Enlargement, and Subretinal fluid) categorises tumours as 'common naevus', 'low-risk naevus', 'high-risk naevus', and 'probable melanoma'. The MOLES system recommends that patients with common naevi (score = 0) undergo review by a community optometrist every two years, ideally with sequential colour photography. For the remaining patients (score ≥ 1), specialist imaging and assessment are recommended, with referral triaged as non-urgent for patients with low-risk (score = 1) or high-risk naevi (score = 2) and urgent for patients with probable melanoma (score > 2).Methods: Lesions flagged as choroidal melanocytic tumours on retinal photographs taken during the Australian National Eye Health Survey were retrospectively analysed by an ocular oncologist. Each lesion was assigned a MOLES score and categorised as common, low-risk, high-risk or probable melanoma.Results: Seventy-seven choroidal naevi were identified. Seventy-five (97%) of the choroidal naevi were categorised as common naevi, with a MOLES score of 0. Two (3%) choroidal naevi had a score of 1 and diagnosed as low-risk naevi due to their size. No naevi had a score of 2 or more.Conclusion: All choroidal naevi detected in this nationally representative population survey were innocuous. This suggests that the vast majority of choroidal melanocytic tumours that are incidentally detected in Australia can be managed in primary eye care settings without the need for specialist referral. MOLES provides a simple evidence-based method for choroidal naevi assessment in primary care.

Current Practices in Pediatric Dermatology Laser Therapy: An International Survey

BACKGROUND AND OBJECTIVES

To date, there are no well-established guidelines regarding laser therapy for the treatment of cutaneous lesions in pediatric patients. We aim to ascertain the types of lasers commonly used, types of lesions treated, and factors that affect the selection of specific laser modalities in pediatric patients.

STUDY DESIGN/MATERIALS AND METHODS

An anonymous online survey was distributed to healthcare providers who treat children with lasers through listservs of four major national and international dermatology and laser organizations.

RESULTS

Outpatient office-based procedure rooms are the most common clinical setting for laser procedures (74.4%), and pulsed dye laser is the most commonly used laser (95.4%). Conditions routinely treated with lasers included port wine stains (95.4%), infantile hemangiomas (81.5%), other vascular lesions (81.5%), scars (77.7%), and hair (60.8%). 84.4% of respondents expressed concern about general anesthesia in patients <2 years old. Nevi of Ota is treated with laser more frequently (52.3%) than other pigmented lesions.

LIMITATIONS

Limited generalizability of case examples to general conditions.

CONCLUSIONS

Vascular lesions are the most common lesions treated with lasers in pediatric dermatology patients, and most providers are using these devices in the outpatient setting. Many providers are concerned about the effects of repeated general anesthesia in infants, and there appears to be a trend toward providing laser therapy in the outpatient setting without general anesthesia. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Exposure to Bile Leads to the Emergence of Adaptive Signaling Variants in the Opportunistic Pathogen Pseudomonas aeruginosa

The chronic colonization of the respiratory tract by the opportunistic pathogen Pseudomonas aeruginosa is the primary cause of morbidity and mortality in cystic fibrosis (CF) patients. P. aeruginosa has been shown to undergo extensive genomic adaptation facilitating its persistence within the CF lung allowing it to evade the host immune response and outcompete co-colonizing residents of the lung microbiota. However, whilst several studies have described the various mutations that frequently arise in clinical isolates of P. aeruginosa, the environmental factors governing the emergence of these genetic variants is less well characterized. Gastro-oesophageal reflux has recently emerged as a major co-morbidity in CF and is often associated with the presence of bile acids in the lungs most likely by (micro) aspiration. In order to investigate whether bile may select for genetic variants, P. aeruginosa was experimentally evolved in artificial sputum medium, a synthetic media resembling environmental conditions found within the CF lung. Pigmented derivatives of P. aeruginosa emerged exclusively in the presence of bile. Genome sequencing analysis identified single nucleotide polymorphisms (SNPs) in quorum sensing (lasR) and both the pyocyanin (phzS) and pyomelanin (hmgA) biosynthetic pathways. Phenotypic analysis revealed an altered bile response when compared to the ancestral P. aeruginosa progenitor strain. While the recovered pigmented derivatives retained the bile mediated suppression of swarming motility and enhanced antibiotic tolerance, the biofilm, and redox responses to bile were abolished in the adapted mutants. Though loss of pseudomonas quinolone signal (PQS) production in the pigmented isolates was not linked to the altered biofilm response, the loss of redox repression could be explained by defective alkyl-quinolone (AQ) production in the presence of bile. Collectively, these findings suggest that the adaptive variants of P. aeruginosa that arise following long term bile exposure enables the emergence of ecologically competitive sub-populations. Altered pigmentation and AQ signaling may contribute to an enhancement in fitness facilitating population survival within a bile positive environment.

Pigmented primary epithelial tumor of the sella: A report of an intriguing case

This is a report of an uncommon primary pigmented papillary epithelial tumor of the sella in a 38-year-old man, who presented with clinicoradiological features of pituitary adenoma. Histologically, the tumor showed features reminiscent of choroid plexus papilloma, that is, conspicuous papillary epithelial morphology with presence of intacytoplasmic melanin and no mitotic activity. Immunohistochemically, the tumor was positive for pancytokeratin (AE1/AE3), S-100 protein and CD56, while it was negative for glial fibrillary acid protein, thyroid transcription factor-1, epithelial membrane antigen, other cytokeratins and pituitary hormones. These findings were not typical of any WHO-defined entity and is thus best regarded as a pigmented papillary epithelial tumor of sella of uncertain histogenesis. The present case is a valuable addition to the spectrum of primary pigmented papillary epithelial tumors originating at an unusual location.

Pigmented Actinic Keratosis: Case Report and Review of an Uncommon Actinic Keratosis Variant that can Mimic Melanoma

Pigmented actinic keratosis is an uncommon variant of actinic keratosis that can mimic melanocytic lesions. A 54-year-old man who presented with a dark lesion on his nasal tip is described; biopsy of the lesion revealed a pigmented actinic keratosis that was treated with cryotherapy using liquid nitrogen. Pigmented actinic keratoses typically appear on sun-exposed areas of the skin as flat hyperpigmented lesions that grow in a centrifugal pattern. Dermoscopy reveals one or more pseudonetworks with hyperpigmented dots or globules. Histopathology shows atypical keratinocytes in the epidermal basal layer and increased melanin content in the epidermis and dermis. Treatment options include liquid nitrogen cryotherapy for solitary lesions and curettage, 5-fluorouracil, imiquimod, ingenol mebutate, photodynamic therapy, or superficial peels for extensive lesions.

Pilar Cyst Pigmented Epithelial Remnants: A Potential Diagnostic Pitfall

Pilar cysts are common cutaneous cysts of follicular origin. They are easy to diagnose clinically and pathologically. Histologic diagnostic difficulties might arise in certain situations, however. Acute inflammation with total destruction of the cyst wall due to rupture with replacement by an abscess formation, foreign body giant cell reaction, and fibrosis could obscure their recognition. Cysts with hybrid lining epithelium could be confused with other cutaneous cysts. Epithelial remnants of the basal layer with loss of the squamous epithelium and shelled out cyst contents might mimic other epithelial cysts and vascular lesions. Few studies focused on the phenomenon of epithelial remnants or epithelial separation of pilar cysts. We report a case of a scalp cyst composed of a single layer of pigmented cuboidal lining epithelium. The initial differential diagnosis was hidrocystoma, solid-cystic hidradenoma, arteriovenous malformation, and lymphangioma. The intraepithelial pigment was melanin. The lining epithelium was positive for cytokeratin cocktail, CK5/6, CK8, CK19, p63, and D2-40 with scattered S-100 protein and melan-A positive melanocytes. Being unaware of the phenomenon of epithelial split in pilar cysts, it was mislabeled as a melanin-pigmented eccrine hidrocystoma. Surgical pathologists should be aware of pilar cysts' epithelial remnants to avoid potential diagnostic pitfalls. An attention to certain histologic hints and knowledge of the immunoprofile of the basal layer should help pathologists avoid this pitfall.

Pigmented Basal Cell Carcinoma Masquerading as a Melanoma

Basal cell carcinoma is the most common skin cancer. Pigmented basal cell carcinoma is an uncommon clinical presentation that can resemble a melanoma. We present the clinical and pathologic features of three individuals whose pigmented basal cell carcinomas masqueraded as melanomas. All of the patients were Hispanic and ranged in age from 63 years to 77 years. They presented with a pigmented lesion that was ultimately diagnosed as a pigmented basal cell carcinoma; one woman had a collision tumor consisting of a pigmented basal cell carcinoma and a seborrheic keratosis. All of the patients had their tumors removed using Mohs micrographic surgery, without recurrence. The clinical differential diagnosis of a black tumor―particularly in patients with darker skin types―should include pigmented basal cell carcinoma in addition to melanoma; a biopsy of the lesion will establish the diagnosis.

Melanotic neuroectodermal tumor of infancy: A rare entity

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare neoplasm with a predilection for the head-and-neck region. Approximately 472 cases reported in literature till date. We report an unusual case of MNTI in a 1-month old child. A 10 cm × 5 cm × 5 cm nontender, firm, deep-seated swelling was seen involving the right zygomatic and maxillary region. Magnetic resonance imaging was suggestive of rhabdomyosarcoma and immunomorphological assessment of the excision specimen revealed the final diagnosis of MNTI. On follow-up, the patient developed recurrence 4 months after surgery and was reoperated. The present case emphasizes that albeit rare, pediatric surgeons and pathologists must always keep in mind the possibility of MNTI while dealing with maxillofacial tumors in infants. Owing to rather nonspecific clinicoradiological features, histopathology supplemented with immunohistochemistry remains the gold standard for diagnosis. Although considered to be a benign tumor, close clinicoradiological follow-up is strongly recommended given the significant risk of recurrence as highlighted by our case.

Acral and Multicentric Pigmented Bowen's Disease in HIV-Positive Patients: Report on Two Unusual Cases

In situ squamous cell carcinoma of the skin (SCCis or Bowen's disease) is a common intraepidermal cutaneous malignancy with a low invasive potential. Acral Bowen's disease is usually solitary, but multiple acral SCCis have been reported. Pigmented Bowen's disease is typically unilesional and characterized by a hyperpigmented plaque with a velvety of keratotic surface, which can eventually simulate melanoma clinically. We describe two HIV-positive patients who presented with multiple pigmented SCCis involving the distal extremities. In patients with immunosuppression, the presence of multiple and hyperpigmented verrucae that clinically do not respond to adequate treatment should raise the differential diagnosis of SCC in situ.

Pigmented transverse nasal band: A distinct presentation

Pigmented transverse nasal band (PTNB) is an interesting morphological entity mainly of cosmetic concern. It is believed to be related to a defect in the development of the nasal cartilages and bones from childhood to adolescence. Some patients may have genetic predisposition. It is asymptomatic in nature and may be associated with certain dermatological conditions such as seborrheic diathesis, dermatosis papulosa nigra, ichthyosis, atopic dermatitis, acne vulgaris, psoriasis, and seborrheic melanosis.

Melanotic intracranial epidermoid: Case report and description of a new subtype

Intracranial epidermoids are generally seen as hypodense nonenhancing lesions on computed tomography scans; and, as T1 hypointense and T2 hyperintense lesions on magnetic resonance imaging (MRI). Unusual radiological findings have been reported earlier. The authors present the case of a 54-year old male patient who had prior intracranial surgery. On MRI, there was a thick peripheral mantle of diffusion restriction with a central core of brilliant T1 hyperintensity and very black T2 hypointensity. The peripheral mantle showing diffusion restriction was heterogeneously T1 hypointense and T2 hyperintense. At surgery, there was a typical pearly white epidermoid peripherally with a greenish-brown centre. Pathology showed abundant extracellular melanin which was also found in the basal layer. The authors present the first case of a melanin pigmented intracranial epidermoid in literature, describing a new histological subtype.

Clinical and Dermoscopic Features of Pigmented Disseminated Superficial Actinic Porokeratosis: Case Report and Literature Review

INTRODUCTION

Porokeratosis is a benign hyperkeratotic skin tumour due to a clonal proliferation of keratinocytes and is characterised by a telltale annular threadlike configuration along the border of a skin-colored to erythematous papule that can expand centrifugally.

CASE PRESENTATION

We are presenting a clinical and dermoscopic case of pigmented disseminated superficial actinic porokeratosis (DSAP) limited to the upper trunk of a white man with sun-damaged skin. Literature Review and Conclusion: A thorough review of PubMed failed to identify any previous reports on the dermoscopic appearance of pigmented porokeratosis. On dermoscopy, the presence of black dots limited to the periphery of the lesions is due to pigment incontinence and melanophages within the superficial papillary dermis limited to the area below the cornoid lamella. Pigmented DSAP is a unique morphological presentation of porokeratosis, and it is essential to be familiar with its clinical and dermoscopic presentation.

Tumors and Related Lesions of the Pigmented Epithelium

Several tumors and pseudotumors can arise from the iris pigment epithelium (IPE), ciliary pigment epithelium (CPE), and retinal pigment epithelium (RPE), including cysts of the IPE, solitary congenital hypertrophy of the RPE (CHRPE), multifocal CHRPE ("bear tracks"), congenital simple hamartoma of the RPE, combined hamartoma of the retina and RPE, and acquired epithelioma of IPE, CPE, and RPE. This article describes examples of pigment epithelial tumors and pseudotumors by reviewing the literature and cases on file in the Oncology Service at Wills Eye Hospital. Solitary CHRPE, traditionally believed to be stationary, can show growth in diameter in 83% and can spawn elevated nodular tumors that can progressively enlarge, cause complications, and even evolve into malignant epithelioma (adenocarcinoma). Multifocal CHRPE (congenital grouped pigmentation) has no relationship to familial adenomatous polyposis or Gardner syndrome, despite its similarity to the pigmented fundus lesions seen with those conditions. Congenital simple hamartoma of the RPE is a specific lesion that involves the fovea and does not tend to cause complications. Combined hamartoma, an idiopathic proliferation of RPE cells, blood vessels, and glial cells, is also believed to be a relatively stable lesion but can cause vision loss due to traction. Acquired tumors (adenoma, adenocarcinoma) have features distinct from melanoma clinically and histopathologically. Torpedo maculopathy is a small stable lesion with typical features, resembling a torpedo. There are several intriguing tumors and pseudotumors of the pigmented epithelium that have major clinical and histopathologic importance.

Screening of pigmented Bacillus aquimaris SH6 from the intestinal tracts of shrimp to develop a novel feed supplement for shrimp

AIMS

To develop a novel feed supplement for shrimp using pigmented spore-forming bacterial strains isolated from their gastrointestinal tracts.

METHODS AND RESULTS

Eight pigmented Bacillus strains were selected from the isolates based on high production of heat-stable spores, typical UV-Vis spectra of produced carotenoids (400-550 nm), and free radical scavenging activity of their extracts. Of the eight strains, the red-orange pigmented Bacillus aquimaris SH6 was selected because it showed the highest abundance in shrimp guts (70% population). Whiteleg shrimp (n = 30 per group) fed with SH6 spores, at >3 × 10⁶  CFU g^-1  pellet for 4 weeks had redder colour (score of 21-23 vs 20-22), 2·7-fold higher astaxanthin level (0·69 vs 0·25 μg g^-1 shrimp), 34% higher weight gain (7·18 vs 5·32 g shrimp^-1 ), and 85% higher phenoloxidase activity (OD490  = 0·265 vs 0·143) than shrimp in the control group.

CONCLUSIONS

The result supports the potential use of B. aquimaris SH6 as a feed supplement for promoting the colourization and weight gain, and for enhancing innate immunity of whiteleg shrimp.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates that carotenoids produced by B. aquimaris SH6 can be successfully absorbed and converted to astaxanthin in whiteleg shrimp.

Primary malignant melanoma of oral cavity: A tertiary care center experience

Background:

Primary mucosal malignant melanoma is an extremely rare, aggressive neoplasm accounting for 0.5% of all oral malignancies. Any pigmented lesion in oral cavity should have an index of suspicion, which should be investigated to detect the disease at an early stage and managed appropriately. Melanomas tend to invade locally into the tissue or metastasize more commonly than other malignant tumors of the oral cavity.

Materials and Methods:

We report a retrospective case series of eight patients suffering from primary oral malignant melanoma treated in our department between 2012 and 2014. The details were recorded from the departmental computerized database and patients on follow-up.

Results:

There were six male and two female patients with a mean age of 46.8 years. Hard palate was the most common affected site in oral cavity. Pigmented lesion\ulcer was the most common presenting symptom. Majority of patients (5 patients) were diagnosed with Stage III (distant metastasis), two patients in Stage II, and one patient in Stage I. Three patients were treated with definitive surgery and five patients with palliative chemotherapy in view of distant disease. Following surgery, two of them required adjuvant chemoradiotherapy in view of nodal spread. Patients had a mean follow-up of 10.5 months (range: 8–26 months). Patients treated with definitive surgery had a mean survival rate of 16 months (range: 10–26 months), with local recurrence in one patient. Metastatic melanoma patients treated with palliative chemotherapy had a mean disease control rate of 5 months (range 5–9 months).

Conclusion:

Oral melanoma carries dismal prognosis with a 5-year survival rate of 5–20%. Early detection of the lesion, proper evaluation, and appropriate treatment are very important to cure the disease.

Two adjacent individual fibroepithelioma of Pinkus of the umbilicus-one pink, one pigmented-a case report and review of the literature

We present a unique case of separate and independent adjacent fibroepitheliomas of Pinkus (FeP) arising from the umbilicus in an 83-year-old man. Of further interest, one is pigmented and the other nonpigmented. Clinical, dermatoscopic and histopathological images are provided.

A review of the published literature is undertaken to attempt to assess the incidence of pigmented versus nonpigmented FeP. Of 24 published FeP cases, 10 (41.7%) have been pigmented. Thus to date pigmented FeP comprise approaching one-half of all reported cases.

WNT-activated medulloblastoma with melanotic and myogenic differentiation: Report of a rare case

Medulloblastoma (MB) with melanotic and myogenic differentiation, previously known as melanotic medullomyoblastoma, is an extremely rare histological variant of MB showing melanocytic as well as skeletal muscle differentiation. Only 10 cases of this rare tumor have been reported in the literature to date. We report this case of a 2-year-old male child who presented with a midline cerebellar mass, which on histopathological examination showed classic MB intermixed with cells containing melanin pigment, along with rhabdomyoblasts, spindle cells and occasional strap cells, which corresponded to WNT subgroup on molecular classification. The cell of origin of this MB variant is likely to be neural crest-derived stem cells which are capable of multilineage differentiation. Significant findings from previous reports and important differential diagnoses are discussed. Documentation of these tumors is important to characterize the clinical behaviour and to identify distinct genetic features, if any.

Effects of type of light on mouse circadian behaviour and stress levels

Light is the principal synchronizing environmental factor for the biological clock. Light quantity (intensity), and light quality (type of light source) can have different effects. The aim of this study was to determine the effects of the type of light experienced from the time of birth on mouse growth, circadian behaviour and stress levels. We raised pigmented and albino mice under 24 h light-dark cycles of either fluorescent or white light-emitting diode (LED) light source during the suckling stage, and the animals were then exposed to various light environments after weaning and their growth rate, locomotor activity and plasma corticosterone concentration were measured. We found that the type of light the animals were exposed to did not affect the animals' growth rates or stress levels. However, we observed significant effects on the expression of the locomotor activity rhythm under low contrast light-dark cycles in pigmented mice, and under constant light in both albino and pigmented mice. These results highlight the importance of environmental light quality (light source) on circadian behavioural rhythms, and the need for close monitoring of light environments in animal facilities.

Pigmented keratocystic odontogenic tumor: A case report with review of the literature

Keratocystic odontogenic tumor (KCOT) is a relatively rare benign neoplasm of odontogenic origin. The squamous epithelium of KCOT usually does not contain melanocytes, however, pigmented KCOT has been documented, albeit extremely rarely. In the present study, we described an additional case of pigmented KCOT and review the clinicopathological features of this extremely rare lesion. A 23-year-old Japanese female presented with a relatively well-circumscribed round unilocular radiolucency that impacted the third molar in her right mandibula. Surgical resection was performed subsequent to a clinical diagnosis of KCOT. Histopathological study of the resected mandibular cyst showed that it was covered by a parakeratinized stratified squamous epithelium, which had slightly enlarged hyperchromatic nuclei. On the luminal surface, a wavy layer of parakeratin was observed. In addition, dendritic melanocytes without atypia were observed in approximately half of the squamous epithelium. Immunohistochemical analyses revealed that these melanocytes were positive for S-100 protein, Melan-A and HMB-45. Therefore, a diagnosis of pigmented KCOT was made. Review of the clinicopathological features of the previously reported cases of pigmented KCOT as well as the present case revealed that: i) this lesion occurs mostly in young persons (average age, 18 years) and shows female predominance; ii) most cases are solitary and involve the mandibula; and iii) the reported incidence is 0.36-10.6% and this difference may be associated with ethnicity. Thus, we described the ninth reported case of pigmented KCOT. The mechanism by which melanocytes appear and the difference in ethnic prevalence remain unclear. Additional clinicopathological studies are needed to clarify these issues.

Pigmented median raphe cyst of the penis with consideration of the possible mechanism of melanocytic colonization: A case report

Median raphe cyst is a rare lesion located on the median raphe. The cyst wall is lined by cuboidal to columnar cells, transitional (urothelial) cells, stratified squamous cells or a mixture of these. The normal urethral mucosa and the median raphe cyst usually lack melanocytes and/or melanin pigment. However, albeit extremely rare, the presence of melanin pigment and/or melanocytes in median raphe cyst, namely pigmented median raphe cyst, has been previously reported. The current case report presents the sixth case of pigmented median raphe cyst and discusses the possible mechanism of melanocytic colonization in this tumor. A 48-year-old male presented with a nodule on the ventral surface of the penis. Histopathological study revealed that the cyst wall was covered by uniform bland cuboidal to urothelial cells. The peculiar observation was the presence of dendritic melanocytes among the epithelial cells. Therefore, a diagnosis of pigmented median raphe cyst was determined. Immunohistochemically, stem cell factor and endothelin-1 were not expressed in the epithelial cells of the cyst wall. It is well-known that melanocytes are rarely found in various non-melanocytic tumors, a phenomenon termed 'colonization'. The mechanism by which melanocytes appear in median raphe cyst remains unclear. The present report is the first to demonstrate that melanocytic proliferation and differentiation factors, such as stem cell factor and endothelin-1, are not involved in the pigmentation of median raphe cyst. In addition, aberrant melanocytic migration may contribute to the development of this type of lesion.

Pigmented pilomatricoma: an underrecognized variant

The presence of melanin pigment and/or melanocytes in pilomatricoma has been rarely documented. In this study, we analyzed the incidence and clinicopathological features of pigmented pilomatricoma. Fifty-seven consecutive pilomatricoma cases from 53 Japanese patients were examined in this study. In fourteen cases (24.6%), pigmentation was observed in pilomatricoma. This variant equally affected in males and females, and the common locations were the upper arm and face. Proliferation of dendritic melanocytes was observed within basaloid cell nests in all cases, and melanin pigment was also present within the cytoplasm of the basaloid cells in 11 cases. Melanin pigment was also present in the shadow cells in 7 cases. The incidence of pigmented pilomatricoma as documented in previous reports is approximately 10%. However, our analysis revealed that pigmented pilomatricoma was found in 24.6% of Japanese cases of pilomatricoma, thus, this variant is not uncommon and may be under-recognized.

Pigmented basal cell carcinoma: Cytological diagnosis and differential diagnoses

Pigmented basal cell carcinoma is a rare cutaneous neoplasm with only a few cases reported so far. Review of the literature yielded only an occasional fine-needle aspiration report of the cytologic features of the tumor.We report a rare case of pigmented basal cell carcinoma occurring on the thigh of a 55-year-old woman. The cytological features are described with discussion over the possible differential diagnoses.

Pigmented adenoid cystic carcinoma of the ear skin arising from the epidermis: a case report with immunohistochemical studies

Adenoid cystic carcinoma (ACC) in the skin is very rare; only about 60 cases have been reported. Herein presented is a case of pigmented ACC arising from epidermis of the ear skin. An 85-year-old man presented black tumor of the right ear. Dermatologists' diagnosis was basal cell carcinoma (BCC). Large biopsy was obtained. The biopsy showed proliferation of atypical basaloid cells arranged in a cribriform pattern. The tumor cells were continuous with epidermis, as if it arose from the epidermis. Focal areas show melanin deposition in the tumor cells. Mucin stains showed that the tumor cells and tubular lumens contained acidic mucin. Immunohistochemically, the tumor cells were positive for cytokeratin (CK) AE1/3, CK34BE12, CK5/6, CK7, CK14, p63, alpha-smooth muscle actin (ASMA), S100 protein, p53, Ki-67 (labeling 85%), KIT, PDGFRA and CD56. The tumor cells were negative for CK CAM5.2, CK8, CK18, CK19, CK20, EMA, desmin, CEA, HMB45, CD10, CD34, neuron-specific enolase, chromogranin, synaptophysin, CDX2, MUC1, MUC2, MUC5AC and MUC6. HMB-positive and S100-positive melanocytes were seen in a very few areas. Since characteristic cribriform pattern was recognized in the tumor and the tumor showed epithelial markers, myoepithelial markers (CD14, p63, ASMA, S100 protein) and KIT, the pathological diagnosis of ACC was made. No distant and lymph node metastasis is now seen. The patient will be treated by complete resection. The present cutaneous ACC was unique in that the ACC arose from the epidermis, had melanin pigment, and occurred in ear skin.

Follicular thyroid adenoma dominated by spindle cells: report of two unusual cases and literature review

Primary spindle cell neoplasms of the thyroid gland are quite rare. They encompass a heterogeneous group of benign and malignant lesions of mesenchymal and epithelial origin. We herein describe two unusual follicular thyroid adenomas dominated by spindle cells with occasional areas of colloid-forming follicular differentiation. The tumors affected a 77-year woman and a 70-year old man; both had a long-history of monoclonal gammopathy of unknown significance (MGUS). One tumor presented as a large cold thyroid nodule and the other was an autopsy finding. The tumors were predominantly composed of fibroblast-like spindled cells. One case showed prominent meningioma-like concentric perivascular arrangement and contained cytoplasmic melanin-like pigment. Stromal hyalinization was a prominent feature of both. By immunohistochemistry, the spindled cells expressed vimentin, pankeratin (KL1), thyroglobulin and TTF1 consistent with a follicular differentiation. They did not stain with calcitonin, CEA and other lineage-specific mesenchymal, neuroendocrine and melanocytic markers. There was no evidence of metastasis at autopsy (case 2) or at last follow-up 2 years after surgery (case 1). These cases demonstrate the diversity of follicular thyroid neoplasms and the unusual occurrence of extensive spindle cell metaplasia. These uncommon lesions need to be distinguished from spindle cell medullary carcinoma, paucicellular spindle cell anaplastic carcinoma, spindle cell foci in papillary and follicular carcinoma, solitary fibrous tumor and other rare benign and malignant mesenchymal lesions.

Pigmented basal cell carcinoma successfully treated with 5% Imiquimod cream

Basal cell carcinoma (BCC) is the most common malignant skin tumor, amongst which the nodular, nodulo ulcerative and superficial types comprise nearly 80% of all BCCs. Topical Imiquimod, an immune response modifier has been found to be effective in superficial and nodular types of BCC with histological clearance rates of up to 100%. We report our experience of treatment a large pigmented BCC on the face with topical Imiquimod 5% cream.