Search

Granular cell tumors (GCTs) are rare, indolent neoplasms classically characterized by eosinophilic granular cytoplasm, infiltrations of polygonal cells in the collagenous stroma, and pustulo‐ovoid bodies of Milian. We describe a case of a 10‐year‐old female presenting with a GCT of the upper arm, remarkable for positive Melan‐A expression without additional melanocytic features. The differentiation between granular cells versus melanocytic neoplasms carries significant implications for clinical management, and such diagnoses should be considered carefully in the setting of unusual immunophenotypes. [ABSTRACT FROM AUTHOR]

Mohs micrographic surgery using MART-1 immunostain in the treatment of invasive melanoma and melanoma in situ. Keywords: Mohs micrographic surgery; MMS; Melanoma; Lentigo maligna; Immunohistochemistry; MART-1; MELAN-A; HMB-45; MITF; SOX-10; S-100; Ki-67; MC1R; PRAME; pHH3; p16 EN Mohs micrographic surgery MMS Melanoma Lentigo maligna Immunohistochemistry MART-1 MELAN-A HMB-45 MITF SOX-10 S-100 Ki-67 MC1R PRAME pHH3 p16 2769 2772 4 11/02/23 20231201 NES 231201 Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s00403-023-02711-5. Though overall use of S-100 is limited due to low specificity for atypical melanocytes, in cases of MMS for desmoplastic melanoma, S-100 appeared more reliable than both MART-1 and HMB-45. [Extracted from the article]

Introduction: The gastrointestinal neuroectodermal tumor (GNET) is a rare mesenchymal tumor mainly arising in the gastrointestinal tract. Case Presentation: Herein, we describe a case of GNET that had been previously diagnosed as metastatic primitive neuroectodermal tumor (PNET) to the lung and liver and received 30 cycles of adjuvant chemotherapy. The physical exam showed a palpable mass in the lower right quadrant of the abdomen. The tumor mass was composed of diffuse sheets of epithelioid tumor cells, in which osteoclast-like giant cells scattered unevenly. Immunohistochemically, the tumor cells were diffusely positive for SOX10, CD99, and CD56, patchy positive forpan-CK, and negative fordesmin, HMB-45, Melan-A, and chromogranin. Conclusions: Consistent with previous studies that reported a secondary GNET following chemotherapy, we assume that the chemotherapy might trigger the tumorigenesis of GNET in this case. [ABSTRACT FROM AUTHOR]

Malignant melanoma of the rectum is an exceedingly rare type of cancer with an aggressive presentation, comprising up to 4% of all anorectal cancers. Presentation of this cancer tends to occur in individuals in their late 80s, with nonspecific symptoms such as anal pain or rectal bleeding. Diagnosing rectal melanoma, especially in early stages, is difficult due to its amelanotic presentation and lack of pigmentation, which results in poor remission rates and prognosis. Furthermore, surgical treatment is difficult as these types of malignant melanomas tend to spread along submucosal planes; thus, complete resections are impractical, especially if caught later. In this case report, we present the radiological and pathological features as seen in a 76-year-old man diagnosed with rectal melanoma. Based on his presentation of a heterogeneous bulky anorectal mass with extensive local invasion, initial impressions were colorectal carcinoma. However, surgical pathology found the mass to be a c-KIT+ melanoma, with positive SOX10, Melan-A, HMB-45, and CD117 biomarkers. While the patient was treated with imatinib, the melanoma was too widespread and aggressive, leading to progression and ultimately death.

Clear cell tumors of the lung (CCTL), or “sugar tumors” of lung, are very uncommon lesions and are mostly benign perivascular epithelioid cell (PEC) tumors with no specific morphologic features. Fewer than 100 cases have been reported; the aggressive nature demonstrated in sporadic reports has rarely been described in the literature. Although the course is generally described as benign, eight reported cases showed malignant behavior. We report a case of a PEC with a malignant presentation in a young man, correlating the main characteristics of the tumor with other cases reported in the literature to better elucidate this rare presentation. We also performed a literature review of reports on benign and malignant CCTL cases, with a focus on clinical, imaging, and immunohistochemical differentiation. CCTLs are rare tumors that require histopathological and immunohistochemical confirmation; to date, criteria that can predict malignant evolution are lacking. [ABSTRACT FROM AUTHOR]

A 50-year-old lady presented with complaints of a progressively increasing anal mass and occasional bleeding per rectum for the past 4 months. Examination revealed an ulcero-proliferative growth in the anal canal, whose biopsy was suggestive of malignant melanoma. Inguinal lymph nodes, though enlarged, did not show evidence of malignant deposits on FNAC. Radiological investigations revealed a T3 lesion with no evidence of nodal metastasis. She underwent local excision of the mass with uneventful intraoperative and postoperative periods. The purpose of this report is to highlight the formidable challenges encountered in diagnosing this rare tumour, with potential implications for misdiagnosis, particularly within a resource-poor setting. This case highlights the importance of resource-appropriate approaches and surgical options available in a tertiary care hospital in North India. [ABSTRACT FROM AUTHOR]

Clear cell tumors of the lung (CCTL), or “sugar tumors” of lung, are very uncommon lesions and are mostly benign perivascular epithelioid cell (PEC) tumors with no specific morphologic features. Fewer than 100 cases have been reported; the aggressive nature demonstrated in sporadic reports has rarely been described in the literature. Although the course is generally described as benign, eight reported cases showed malignant behavior. We report a case of a PEC with a malignant presentation in a young man, correlating the main characteristics of the tumor with other cases reported in the literature to better elucidate this rare presentation. We also performed a literature review of reports on benign and malignant CCTL cases, with a focus on clinical, imaging, and immunohistochemical differentiation. CCTLs are rare tumors that require histopathological and immunohistochemical confirmation; to date, criteria that can predict malignant evolution are lacking.

Simple Summary: Oncology in pet rabbits (Oryctolagus cuniculus) has emerged in recent years as medical treatments are required with increasing frequency. In this report, we describe a case of cutaneous malignant melanoma occurring in the scrotum in a wild rabbit, with testicular metastases, as an unusual metastatic site only described in human patients to date. Case presentation and gross, histopathological, and immunohistochemical findings are detailed. Descriptions of the biological behaviour of spontaneous tumours may serve to improve current knowledge in animal species and humans in which the same neoplasm occurs. Furthermore, the increasing popularity of rabbits as pets allows for more data on the spontaneous occurrence of cancer. Melanocytic skin tumours have been rarely described in pet rabbits, and exposure to UV light in sparsely haired areas has been hypothesised to play a cancerogenic role. Here, we describe a case of cutaneous malignant melanoma arising from the skin of the scrotum in an 8-year-old male wild rabbit, with testicular metastases as an unusual metastatic site for melanoma reported in humans to date. The tumour was nearly 5 cm in size, firm, and highly pigmented, with multifocal superficial ulcerations and large areas of intratumoural necrosis. The adjacent testis was 1.5 cm, multinodular, and black, obscuring tissue morphology. Histologically, the dermis was expanded by an infiltrative, densely cellular neoplasm composed of nests and sheets of polygonal to spindle neoplastic melanocytes, supported by scant fibrovascular stroma. Neoplastic cells showed intermediate N/C ratio, moderate basophilic cytoplasm, often obscured by abundant brownish granular pigment, and eccentric nuclei with prominent nucleoli. Cellular pleomorphism and nuclear atypia were severe, and high mitotic activity was observed. Diffuse dermal lymphovascular invasion was also observed. The testis was delimited by a thin tunica albuginea, and the parenchyma was largely obscured in its morphology by densely packed neoplastic cells. Seminiferous tubules, lined with a thin basement membrane and containing neoplastic and scattered spermatogenic cells, were occasionally observed. Neoplastic cells within the skin and the testis were positive for HMB-45, Melan-A, and S-100. The growing popularity of rabbits as pets allows for a greater ability to accumulate data on the spontaneous occurrence of tumours in these animals. Furthermore, descriptions of the biological aspects of spontaneously occurring tumours may serve to improve current knowledge in animal species and humans in which the same neoplasm may occur. [ABSTRACT FROM AUTHOR]

Malignant melanoma of the rectum is an exceedingly rare type of cancer with an aggressive presentation, comprising up to 4% of all anorectal cancers. Presentation of this cancer tends to occur in individuals in their late 80s, with nonspecific symptoms such as anal pain or rectal bleeding. Diagnosing rectal melanoma, especially in early stages, is difficult due to its amelanotic presentation and lack of pigmentation, which results in poor remission rates and prognosis. Furthermore, surgical treatment is difficult as these types of malignant melanomas tend to spread along submucosal planes; thus, complete resections are impractical, especially if caught later. In this case report, we present the radiological and pathological features as seen in a 76-year-old man diagnosed with rectal melanoma. Based on his presentation of a heterogeneous bulky anorectal mass with extensive local invasion, initial impressions were colorectal carcinoma. However, surgical pathology found the mass to be a c-KIT+ melanoma, with positive SOX10, Melan-A, HMB-45, and CD117 biomarkers. While the patient was treated with imatinib, the melanoma was too widespread and aggressive, leading to progression and ultimately death. [ABSTRACT FROM AUTHOR]

Angiomyolipomas are usually found in the kidneys of patients with tuberous sclerosis. They occur less frequently in organs such as the liver, the oral cavity, the nasal cavity, the heart, the large intestines, and the lungs. Angiomyolipomas of the skin are extremely rare, and cutaneous angiomyolipomas generally occur on the elbow, the ends of digits, the ear, and the glabella. Herein we present a rare case of angiomyolipoma occurring on the face--specifically, the right upper eyelid. We propose that upper eyelid angiomyolipoma is a hamartomatous, rather than neoplastic, lesion. Although angiomyolipoma in the periocular area is rare, it should be considered in the differential diagnosis of clinically benign masses. and regular follow-up is warranted. [ABSTRACT FROM AUTHOR]

Background: Perivascular epithelioid cell tumor of the gastrointestinal tract (GI PEComa) is a rare mesenchymal neoplasm. GI PEComa is mostly observed in the colon and has a marked middle-aged female predominance. PEComa has no typical clinical or imaging manifestations or endoscopic characteristics. Therefore, the diagnosis of this disease mostly relies on pathological findings. HMB-45 is a sensitive immune marker of PEComa. Case presentation: We reported a case of a middle-aged female with sigmoid colon PEComa. To exclude carcinogenesis, the large basal polyp in the sigmoid colon was removed by endoscopic mucosal resection (EMR). Immunohistochemistry analysis results showed that this lesion expressed HMB-45, which is a characteristic melanin marker of PEComa. Finally, the lesion was diagnosed as sigmoid colon PEComa. At the time of submission of this report, surgical resection was the primary treatment for PEComa. Though the characteristics of tumor biology and clinical behavior in PEComa are not clear, the boundary is clear, and the tumor can be completely removed. However, close follow-up is required after the surgery because of the lesion's undetermined benign and malignant nature. Conclusion: The present case study emphasizes the importance of pathological diagnosis. Therefore, upon finding gastrointestinal polyps with a mucosal ulcer under endoscopy, the GI PEComa diagnosis should be considered. It is necessary to detect the characteristic melanin markers of PEComa. Due to the rarity of these cases, challenges are faced in diagnosing and treating PEComa. [ABSTRACT FROM AUTHOR]

Fat‐poor leiomyomatous angiomyolipoma, which is similar to smooth muscle tumors, is positive for smooth muscle markers and melanocytic marker human melanin black 45 (HMB‐45). We report a case of fat‐poor leiomyomatous angiomyolipoma arising from renal parenchyma negative for HMB‐45 diagnosed by combined staining with melanocytic markers HMB‐45 and Melan‐A. [ABSTRACT FROM AUTHOR]

Background: Renal angiomyolipomas (AMLs) are rare, benign mesenchymal tumors of the kidney. Asian data on the prevalence of the subtypes of AMLs and their association with tuberous sclerosis are sparse prompting us to evaluate the clinicopathological characteristics of these tumors. Materials and Methods: We included cases diagnosed from 2001 to 2021 extracting demographic details, clinical presentation, syndromic association with tuberous sclerosis, and preoperative clinicoradiological features from the electronic medical records. Results: Ninety-five cases of adult renal AML were diagnosed among 2402 renal tumors, a prevalence of 3.95%. Forty tumors (42%) were detected incidentally; two patients had life-threatening retroperitoneal hemorrhage. Tuberous sclerosis complex (TSC) was associated with ten cases (10.5%). These patients were a decade younger than those in the non-TSC group (P = 0.008) and had bilateral, multiple, and larger tumors (P = 0.0009, 0.001, and 0.047, respectively). Microscopically, classic and epithelioid subtypes were seen in 87 (91.6%) and 8 cases (8.4%), respectively. Hemorrhage was more common in the epithelioid subtype (P = 0.13). HMB-45, melan-A, and smooth muscle actin immunohistochemistry were useful in cases which lacked the prototypical classic histology and for confirming a diagnosis of epithelioid AML. Conclusions: The prevalence of renal AML in our series was four times higher, and the mean age at diagnosis was a decade earlier than that reported in Western literature but similar to data from two Asian countries. Similar studies from other countries will help ascertain if these differences in prevalence can be attributed to ethnic differences.

Abstract Fat‐poor leiomyomatous angiomyolipoma, which is similar to smooth muscle tumors, is positive for smooth muscle markers and melanocytic marker human melanin black 45 (HMB‐45). We report a case of fat‐poor leiomyomatous angiomyolipoma arising from renal parenchyma negative for HMB‐45 diagnosed by combined staining with melanocytic markers HMB‐45 and Melan‐A.

Background: Renal angiomyolipomas (AMLs) are rare, benign mesenchymal tumors of the kidney. Asian data on the prevalence of the subtypes of AMLs and their association with tuberous sclerosis are sparse prompting us to evaluate the clinicopathological characteristics of these tumors. Materials and Methods: We included cases diagnosed from 2001 to 2021 extracting demographic details, clinical presentation, syndromic association with tuberous sclerosis, and preoperative clinicoradiological features from the electronic medical records. Results: Ninety-five cases of adult renal AML were diagnosed among 2402 renal tumors, a prevalence of 3.95%. Forty tumors (42%) were detected incidentally; two patients had life-threatening retroperitoneal hemorrhage. Tuberous sclerosis complex (TSC) was associated with ten cases (10.5%). These patients were a decade younger than those in the non-TSC group (P = 0.008) and had bilateral, multiple, and larger tumors (P = 0.0009, 0.001, and 0.047, respectively). Microscopically, classic and epithelioid subtypes were seen in 87 (91.6%) and 8 cases (8.4%), respectively. Hemorrhage was more common in the epithelioid subtype (P = 0.13). HMB-45, melan-A, and smooth muscle actin immunohistochemistry were useful in cases which lacked the prototypical classic histology and for confirming a diagnosis of epithelioid AML. Conclusions: The prevalence of renal AML in our series was four times higher, and the mean age at diagnosis was a decade earlier than that reported in Western literature but similar to data from two Asian countries. Similar studies from other countries will help ascertain if these differences in prevalence can be attributed to ethnic differences. [ABSTRACT FROM AUTHOR]

Background: Updates of treatment methods of stable vitiligo are needed to give better outcomes with a shorter duration of treatment. Objective: To test the effect of transdermal 5‐fluorouracil (5‐FU) delivery using fractional CO2 (FrCO2) laser versus intralesional 5‐FU injection, with narrow‐band type ultraviolet B (UVB) (NB‐UVB) therapy after both, in the treatment of stable vitiligo. Patients and methods: The present study comprised 40 patients with nearly symmetrical stable vitiligo lesions. The left side was treated with FrCO2 laser followed by topical 5‐FU (FrCO2 + 5‐FU), while the right side was treated with 5‐FU intradermal injection. Both procedures were done at 2‐week intervals for 3 sessions followed by 24 sessions of narrow‐band UVB for both sides. Results: Repigmentation was demonstrated on the left side of 90% of patients and the right side of 85% of patients. As much as >50% improvement was demonstrated on the left side of 50% of patients, and the right side of 55% of patients. Intralesional 5‐FU showed a statistically significant difference in repigmentation compared to FrCO2 + 5‐FU. Conclusion: Both 5‐FU injection and FrCO2 + 5‐FU were effective therapeutic modalities for vitiligo. Patients were more compliant with FrCO2 + 5‐FU. [ABSTRACT FROM AUTHOR]

Melanocytic skin tumours have been rarely described in pet rabbits, and exposure to UV light in sparsely haired areas has been hypothesised to play a cancerogenic role. Here, we describe a case of cutaneous malignant melanoma arising from the skin of the scrotum in an 8-year-old male wild rabbit, with testicular metastases as an unusual metastatic site for melanoma reported in humans to date. The tumour was nearly 5 cm in size, firm, and highly pigmented, with multifocal superficial ulcerations and large areas of intratumoural necrosis. The adjacent testis was 1.5 cm, multinodular, and black, obscuring tissue morphology. Histologically, the dermis was expanded by an infiltrative, densely cellular neoplasm composed of nests and sheets of polygonal to spindle neoplastic melanocytes, supported by scant fibrovascular stroma. Neoplastic cells showed intermediate N/C ratio, moderate basophilic cytoplasm, often obscured by abundant brownish granular pigment, and eccentric nuclei with prominent nucleoli. Cellular pleomorphism and nuclear atypia were severe, and high mitotic activity was observed. Diffuse dermal lymphovascular invasion was also observed. The testis was delimited by a thin tunica albuginea, and the parenchyma was largely obscured in its morphology by densely packed neoplastic cells. Seminiferous tubules, lined with a thin basement membrane and containing neoplastic and scattered spermatogenic cells, were occasionally observed. Neoplastic cells within the skin and the testis were positive for HMB-45, Melan-A, and S-100. The growing popularity of rabbits as pets allows for a greater ability to accumulate data on the spontaneous occurrence of tumours in these animals. Furthermore, descriptions of the biological aspects of spontaneously occurring tumours may serve to improve current knowledge in animal species and humans in which the same neoplasm may occur.

Background: Anorectal melanoma is a rare disease with a poor prognosis. Symptoms are often nonspe- cific, which complicates preoperative diagnosis. Here, we describe the establishment of MELS, a new anorectal melanoma cell line derived from resection of a rectal tumor in a 40-year-old Japanese man. Methods: Histological, electron microscopic, and immunohistochemical features of S-100, HMB-45, Melan-A, and NSE positivity of the tumor were typical of surgically resected anorectal melanoma. Results: MELS cells are round or oval and have sharp thorn-like protrusions on some or all cell membranes. The cells form irregular attached colonies with numerous floating cells in two-dimensional culture. Transmission electron microscopy revealed that some MELS cells have cytoplasmic melanosomes. Immunocytochemically, MELS cells and surgical tissues had the same staining pattern. MELS cells had lower growth rates than Caco-2 (a colon adenocarcinoma cell line) and A375 (a cutaneous melanoma cell line) cells. Oxaliplatin and irinotecan were more effective in MELS cells than in Caco-2 and A375 cells. Conclusions: No previous report provided detailed clinical information on an anorectal melanoma cell line. Thus, MELS cells should improve our understanding of the biological characteristics of anorectal melanoma and provide a novel platform for examining the effects of therapies for anorectal melanoma. [ABSTRACT FROM AUTHOR]

Background: Reptiles have been suggested to be a suitable model for the histological and histochemical aspects even better than other used experimental mammals. Melanomacrophage centers (MMCs) are aggregations of macrophage-like cells and pigments including melanin, hemosiderin, and lipofuscin. MMCs found mainly in different tissues of nonmammalian vertebrates. MMCs are helpful biomarkers for a variety of stresses as environmental pollutants. Aim: This study was designed to elucidate the histological, morphometric, histochemical and immunohistochemical characterization of hepatic MMCs in three reptilian species; Uromastyx ornata (Ornate Dabb lizard), Uromastyx aegyptiaca (Egyptian Dabb lizard), and Varanus griseus (Desert Monitor lizard). Methods: Fifteen adult male reptilian animals were divided into; i. Five adult males Ornate Dabb lizard, ii. Five adult males Egyptian Dabb lizard, iii. Five adult males Desert Monitor lizard. Liver paraffin sections of all animals were processed and stained with Hematoxylin and Eosin stain, Masson Trichrome stain for collagen fibres and Perl's Prussian Blue histochemical stain for hemosiderin pigments. Immunohistochemical demonstration of melanin pigments via HMB-45 and macrophage lineage via CD68 immunostains were applied. Histomorphometric assessments of MMCs were also performed. Results: Histomorphometric examinations revealed significant differences between the histomorphometric structures of MMCs among the experimented species. MMCs in Desert Monitor lizard were fewer in number and smaller in size; with decreased melanin pigment contents and macrophage lineages, and increased hemosiderin contents. Conclusion: The significant differences in MMCs among the three reptiles may indicate considerable differences between the immune system of the Desert Monitor lizard and each of the Ornate and Egyptian Dabb Lizards. [ABSTRACT FROM AUTHOR]

Perivascular Epithelioid Cell tumors (PEComas) are rare mesenchymal tumors composed of epithelioid and spindle cells that can be found almost anywhere in the body with predominance for abdominopelvic locations. They are usually diagnosed in middle-aged females and are associated with tuberous sclerosis complex. This report describes an unusual presentation of a malignant retroperitoneal PEComa in an otherwise healthy, young male. Treatment included radical nephrectomy and adrenalectomy followed by medical oncology evaluation.

Cutaneous granular cell tumors (GCTs) are rare tumors that typically exhibit benign clinical behavior and are likely of Schwann cell origin. Some histologic and immunohistochemical variants of GCTs may present challenges due to infiltrative growth patterns, perineural invasion, and expression of Melan-A. In this case report, we present a 27-year-old male who had previously been diagnosed with a typical GCT on the back a few years ago. The current biopsy from the proximal palm demonstrated a cytologically similar tumor with extensive perineural spread and notable positivity for Melan-A. Although uncommon, these features are consistent with the histological appearances of GCTs. The current views on the histogenesis of GCTs, clinical associations, differential diagnosis with melanoma, and histological criteria for malignant GCTs are discussed. A panel of immunohistochemical stains, including Inhibin-α and preferentially expressed antigen in melanoma (PRAME), is proposed for use in rare instances of Melan-A-positive GCTs., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Bobkova et al.)

Angiomyolipoma (AML) is a mesenchymal tumor commonly found in the kidneys. Extra-renal AML is uncommon and especially rare in the nasal cavity. To our knowledge, fewer than five cases of nasal AML are reported in the United States. We present a case of nasal AML in a 65-year-old man with a history of rhinosinusitis and obstruction of the left nasal cavity. The lesion comprised of admixed spindled smooth muscle cells, mature adipose tissue, and thick-walled blood vessels. Smooth muscle differentiation of the spindled cells was confirmed by expression of smooth muscle actin. Surprisingly, melanocytic markers, such as HMB45, were negative. The histologic features and immunoprofile suggest that nasal AML is pathologically distinct from neoplastic AMLs/perivascular epithelioid cell tumors (PEComas) that typically occur in the kidney. We propose that nasal AML is a hamartomatous lesion rather than neoplastic. Although AML is rare in the nasal cavity, it should be considered in the differential diagnosis of clinically benign nasal masses. [ABSTRACT FROM AUTHOR]

Primary gallbladder melanoma (PGM) is a rare malignancy with only sporadic cases reported in the English literature. We performed a systematic review of the cases published in the PubMed, Science Direct and Google Scholar databases with the aim of describing the reported clinicopathologic features of PGM. Thirty-six articles reporting on 39 patients were reviewed. There was a male predominance, with 23 (64 %) of 36 patients being males. The mean age at presentation was 55 ±16 years. Pain in the right upper quadrant was reported in 20/27 (74 %). The average size of the tumor was 3.5 × 1.9 × 1.4 cm. Gallbladder calculi were reported in 7/27 (26 %). A cholecystectomy was performed in 34/38 (89.5 %). Grossly, the tumor mostly (96.5 %) had polypoid appearances and on microscopic examination, the tumor were predominantly comprised of epithelioid cells 12/17 (70.6 %). Mitotic figures and prominent nucleoli were reportedly found in 8/8 (100 %) and 3/3 (100 %) respectively. Junctional melanocytic components were present in 13/21 (61.9 %). Tumor cells were reportedly immunoreactive for S-100 and HMB-45 in all tested cases. Metastasis were reported in 25/36 (69.4 %), with lymph nodes being the most common site (n = 8), followed by brain (n = 6) and liver (n = 4) for metastasis. At a mean follow-up period of 19 +/− 3 months, 16 (48.5 %) of the 33 patients with available survival data were alive and 17/33 (51.5 %) were dead of disease. There is a lack of unified criteria for the diagnosis of PGM, and future studies should aim to resolve this. • Primary Gallbladder Melanoma appears to be more prevalent in elderly males. • Prognosis is poor, with a mortality of 51.5 % at a mean follow-up of 19 ±3 months. • Chemotherapy and cholecystectomy are the mainstay of treatment. • Unified criteria for the diagnosis of PGM are needed. [ABSTRACT FROM AUTHOR]

Melan-A is one of the most commonly used immunohistochemical assays (IHC) in dermatopathology laboratories to detect the presence and outline the distribution of melanocytes. It is a cytoplasmic stain that detects a melanocyte-specific cytoplasmic protein involved in the formation of stage II melanosomes. Clinically, Melan-A is primarily used to detect and confirm melanocytic tumors although it is also positively expressed in adrenal cortical tumors and sex cord stromal tumors. We found that Melan-A also detected and highlighted Henderson–Patterson bodies of molluscum poxvirus. To determine if other melanocytic markers detect molluscum contagiosum bodies, S-100, HMB-45, MITF, and SOX-10 were also tested. In 15 tested molluscum cases, Melan-A stains were positive in all cases, whereas the other tested melanocytic markers were negative. Our results confirm that Melan-A is very sensitive in detecting molluscum contagiosum bodies and could be clinically useful to supplement the hematoxylin and eosin (H&E) in cases that are very inflamed or only have limited biopsy material. [ABSTRACT FROM AUTHOR]

Introduction: Although malignant melanomas (MM) are common in the head and neck region; primary malignant melanoma of the external auditory canal (EAC) is rare. Case Report: We present the case of a 50-year-old symptomatic man with a malignant melanoma of the external auditory canal, which clinically masqueraded as a haemangioma. The patient subsequently developed extensive loco-regional metastasis, requiring extensive surgery. We describe the clinical presentation, differential diagnosis, both clinical and pathological in terms of other pigmented lesions in the external auditory canal, detailed histopathology, and literature review. Conclusion: We want to emphasize the importance of immediate and adequate biopsy of any pigmented lesion in the head and neck region to rule out MM. Also, we emphasize the importance of deep biopsy for proper histopathological assessment in addition to distinguishing it from benign melanocytic nevi, in order to initiate treatment.

Background: Combination therapies have reported to augment the repigmentation in vitiligo. Microneedling (Mn) facilitates drug delivery across the skin barrier. Objective: To evaluate and compare the efficacy and safety of Mn combined with tacrolimus vs Mn alone or tacrolimus 0.1% ointment for treatment of localized and stable vitiligo. Patients and Method: Ninety patients with vitiligo were randomized into three groups: group I received microneedling with tacrolimus, group II microneedling only both at 2 weeks interval for twelve sessions, and group III applied tacrolimus ointment 0.1% twice daily for 6 months. Skin biopsies were taken at baseline and after treatment. Results: The overall improvement (76.6%) was significantly higher in the combined group compared with other groups. Repigmentation was excellent in 66.6 of group I vs 33.3% in the other two groups (P.03). A highly significant improvement of the extremities was observed in the combined group than in the other groups (P <.001). A fewer number of sessions have reported in the combined group (I) than in the microneedling group (II; P <.001). Immunohistochemical results showed a significantly higher expression of HMB‐45 in group I than in other two groups (P.04). Side effects were mild and tolerable in all groups. Conclusion: The combination group has shown promising results over the other two groups. [ABSTRACT FROM AUTHOR]

Pathologists face ongoing challenges distinguishing between benign and malignant melanocytic tumors. PRAME (PReferentially expressed Antigen in Melanoma) has a demonstrated value distinguishing between these types of lesions. However, the sensitivity of single immunohistochemistry is variable. HMB-45 is another valuable marker, but on its own, has a limited ability in setting of primary melanocytic tumors. This study sought to evaluate the diagnostic potential of a dual panel combining PRAME and HMB-45 in the assessment of primary melanocytic tumors. 259 tumors, of which 141 were benign nevi, 31 dysplastic nevi (either low- or high grade dysplasia), and further 87 malignant melanomas, were retrieved from the department's archives and assessed by two experienced dermatopathologists. New sections were stained with PRAME and HMB-45, respectively. For PRAME, a nuclear, and for HMB-45, a cytoplasmic staining, was considered positive and scored as described in the literature on a scale from 0 to 4+. Only dermal component was assessed on HMB-45 stain. PRAME was diffusely expressed in only 1 benign nevus, with focal expression in further 28 compared to 22 diffusely and 103 focally HMB-45-positive benign nevi. 5 high-grade dysplastic nevi showed diffuse PRAME expression in epidermal component, with varying degree of positivity in adjacent dermal compartment, and further 8 dysplastic nevi showed only focal expression. HMB-45 was diffusely expressed in only 2, with focal expression in 23, and no apparent positivity in remaining 6 dysplastic nevi. In invasive melanoma group, PRAME stained >75 % cells in 64/87 tumors, however, 10/87 melanomas were completely negative. HMB-45 was captured diffusely in 49/87 melanomas, 32 showed patchy expression, and 6 tumors were blank negative. Diffuse 4+ PRAME positivity showed superior sensitivity and specificity of 73,6 % and 96,5 %, respectively, compared to HMB-45, 56,3 % and 86,0 %, respectively. No nevi showed double 4+ positivity, however, the sensitivity for double positivity was only 49,4 %. Our results confirm the superiority of PRAME over HMB-45 in the differential diagnosis of melanocytic tumors. However, combined staining can significantly increase specificity, rendering a benign diagnosis more unlikely in a double 4+ diffuse positivity setting. • PRAME is superior to HMB-45 in diagnostic of melanocytic tumors. • Benign melanocytic tumors are rarely or not at all diffusely positive in both PRAME and HMB-45. • Dysplastic nevi are more often PRAME-positive than common nevi. [ABSTRACT FROM AUTHOR]

Primary melanocytic neoplasms in the central nervous system are rare lesions arising from leptomeningeal melanocytes. These lesions produce neural deficits that resemble those of a meningioma or a schwannoma radiologically. A tumor around the left S1 root with an extension into the left paraspinal compartment was identified in a 32-year-old female with persistent left leg pain for 6 months. The tumor was hyperintense on T1-weighted image and hypointense on T2-weighted image with a homogeneous enhancement. The clinical features, radiologic presentations, treatment choice, and pathologic characteristic were illustrated. The treatment outcome was compared with those reported in the previous literature. The tumor was en-bloc resected with the S1 nerve root reserved. Grossly, the tumor was a soft, capsulated, well-circumscribed, black pigmented lesion. Immunohistochemistry revealed that the tumor cells were positive for HMB-45, S-100 protein, and vimentin. The patient's symptoms were greatly relieved postoperatively. No signs of local recurrence were observed. Spinal meningeal melanocytoma inside the nerve root is rare and benign. It is difficult to diagnose and often misdiagnosed as schwannoma or meningioma. HMB-45 has been suggested as a significant marker for the diagnosis of meningeal melanocytoma. Complete surgical resection is recommended as the primary treatment. Radiotherapy, chemotherapy, and other treatments can be selected as adjuvant therapies, but their effects are controversial. The recurrence and metastasis rates also remain unclear. [ABSTRACT FROM AUTHOR]

Cutaneous melanomas are malignant neoplasms whose incidence has increased markedly in the last five decades. Among the primary cutaneous melanomas, the head and neck location represent 17%. Of these, 7 to 16% settle in the outer ear, of which about 60% occur in the helix and anti-helix. External auditory canal involvement is rarely reported and when it occurs, it occurs in the meatus. We report the case of a peasant patient with long-term exposure to sunlight. He presented a lesion of approximately 1×1.5 cm in the dark brown external audi-tory canal with otalgia, otorrhea with the presence of pus, blood accompanied by hearing loss and preatrial and cervical adenopathy, whose diagnosis was confirmed by fine aspiration puncture (PAFF) of the tumor in addition to the study of the postoperative piece that confirmed the result of the PAFF. [ABSTRACT FROM AUTHOR]

An 81-year-old woman with a history of malignant melanoma who presented with dyspnea and fatigue was found to have metastases to the stomach detected on endoscopy. Primary cutaneous malignant melanoma with gastric metastases is a rare occurrence, and it is often not detected until autopsy because of its non-specific manifestations.

The rarity of Clear Cell Sarcoma (CCS) and its overlapping morphology with other soft tissue tumours brings diagnosis under suspicion. Several series have described histopathologic features however, only few series have described cytological features. This series represents cytohistopathological correlation with emphasis on diagnostic difficulties and the role of ancillary studies. This series concerns six patients who presented at our hospital between 2002-2012. FNAC smears showed epithelioid to spindle cells, scattered or in focal clusters or pseudoacinar pattern. Most cells (n=5) had round to oval eccentrically placed nuclei. Multinucleated tumour giant cells and binucleated cells were (n=2) present. The cell clusters (n=2) demonstrated three dimensional clustering and pseudoacinar structures. Necrosis (n=1) was noted. The histopathological pattern showed variable sized nests of uniform plump to spindle cells with clear to pale cytoplasm separated by fine to coarse fibrous septae. Cells were epithelioid (n=2), with nuclear pleomorphism (n=2), prominent nucleoli (n=3), cytoplasmic vacuoles (n=1) and multinucleated giant cells (n=1). The mitotic rate varied from 3 to 11/HPF. Tumour necrosis and bone involvement were seen (n=2). A microcystic growth pattern (n=1) was seen in the locally recurrent tumour. Melanin and Masson-Fontana were negative. All cases were positive for HMB-45 antibodies. Accurate pathologic recognition could aid in the institution of prompt surgery and could delay or avoid recurrences.

We are reporting a case of superficial spreading melanoma (SSM) on left palm of a 37-year-old pregnant housewife. She had a small acquired melanocytic nevus on her left palm since childhood, which changed its consistency and color in the last 4 months. Dermoscopy of the lesion indicated malignant changes. The lesion was managed surgically using split-thickness skin graft. The histopathology report was suggestive of SSM with positive HMB-45 cells. SSM is very rare on the acral site, and it is very difficult to differentiate it from acral lentiginous melanoma. The rarity of the site (acral nonchronic sun damage) with evolution during pregnancy and importance of management approach are reasons for publishing this case.

Oral melanocytic nevi are localized developmental tissue malformations of nevus cells in the oral mucosa. Relatively rare in occurrence compared to their dermal counterparts, considerable debate exists in the literature related to their origin, development and maturation, and their relationship to oral melanocytes.We report two cases of oral melanocytic nevi with classical clinical presentation. The histopathology was consistent with the known patterns of oral melanocytic nevi. Special stains such as Masson Fontana, further substantiated the observation. S-100 and HMB-45 were applied to immunohistochemically elaborate the cell population. Interestingly two distinct cell populations were detected in the lesions. "Type A" cells in the center of the lesion were S-100 positive, indicating a neural origin and immaturity in development, while peripheral "type B" cells stained positive with HMB-45, indicating melanocytic origin and mature development.

Lymphangioleiomyomatosis (LAM) is a rare, slow-growing metastasizing neoplasm in which smooth muscle-like cells infiltrate the lung parenchyma and cause cystic lung damage. The common early symptoms include shortness of breath, pneumothorax, and chest pain. Lymphangioleiomyomatosis mainly involves the lungs, kidneys, and lymph nodes. This study reviews the characteristics of lymphangioleiomyomatosis to identify any possible changes in the prevalence of symptoms of the disease. We conducted a literature review of case reports on lymphangioleiomyomatosis from PubMed and Google Scholar. Variables of interest were age, gender, symptoms, vitals, immunostaining, and radiological findings. Data were transferred to an Excel spreadsheet (Microsoft Corporation, Redmond, WA), and mean, median, standard deviation, frequencies, and proportions were calculated using R version 1.1.456 (RStudio: Integrated Development for R. RStudio, PBC, Boston, MA). Lymphangioleiomyomatosis is a rare case and so not much of the literature could be found online. Thirty-three case reports were included in this study, and females accounted for 78.78% of the presentations. The average age was 38 years, SD 14.41 years. Shortness of breath was the most frequent symptom (60.6%), followed by pneumothorax (57.57%), chest pain (42.42%), cough (24.24%), and pleural effusion (1.25%)., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Shah et al.)

Melanotic schwannomas (MS) are rare variants of schwannomas the occurrence of which is described in case reports only. They usually arise from posterior spinal nerve roots and less commonly from other cells of neural crest origin. Although they are relatively benign tumors in young, aggressive behavior is reported. They occur as isolated tumors or as part of a syndrome named Carney complex. We try to describe the pathology, diagnosis, management, and prognosis of MSs in two different cases: one cervical intramedullary with no recurrence on 5-year follow-up and the other one extramedullary in lumbar region with early recurrence and aggressive course. A brief review of literature is done. [ABSTRACT FROM AUTHOR]

The rarity of Clear Cell Sarcoma (CCS) and its overlapping morphology with other soft tissue tumours brings diagnosis under suspicion. Several series have described histopathologic features however, only few series have described cytological features. This series represents cytohistopathological correlation with emphasis on diagnostic difficulties and the role of ancillary studies. This series concerns six patients who presented at our hospital between 2002-2012. FNAC smears showed epithelioid to spindle cells, scattered or in focal clusters or pseudoacinar pattern. Most cells (n=5) had round to oval eccentrically placed nuclei. Multinucleated tumour giant cells and binucleated cells were (n=2) present. The cell clusters (n=2) demonstrated three dimensional clustering and pseudoacinar structures. Necrosis (n=1) was noted. The histopathological pattern showed variable sized nests of uniform plump to spindle cells with clear to pale cytoplasm separated by fine to coarse fibrous septae. Cells were epithelioid (n=2), with nuclear pleomorphism (n=2), prominent nucleoli (n=3), cytoplasmic vacuoles (n=1) and multinucleated giant cells (n=1). The mitotic rate varied from 3 to 11/HPF. Tumour necrosis and bone involvement were seen (n=2). A microcystic growth pattern (n=1) was seen in the locally recurrent tumour. Melanin and Masson-Fontana were negative. All cases were positive for HMB-45 antibodies. Accurate pathologic recognition could aid in the institution of prompt surgery and could delay or avoid recurrences. [ABSTRACT FROM AUTHOR]

Background: The anorectum is a rare anatomic location for primary melanoma. In many cases the disease is undetected or is misdiagnosed as a benign polyp or hemorrhoids until it reaches an advanced state. The prognosis is poor, due to delayed diagnosis and early distant metastasis. Involvement of the upper gastrointestinal (GI) tract is very rare in anorectal melanoma and has been described in only a few case reports.Case report: An 83-year-old man presented with a 24-hour history of confusion, slurred speech and gait difficulty of abrupt onset. A computed tomography (CT) scan of the brain revealed three hemorrhagic lesions of 18mm, 14mm and 11mm in their greatest dimension in the cerebral hemispheres, specifically the left and the right frontal regions and the left temporal lobe, which were considered to be metastases. Subsequently, upper GI endoscopy revealed multiple small nodules involving the stomach and the duodenum. A non-pigmented anorectal mass 2cm in diameter was found on colonoscopy.Results: Biopsy of the lesions in the stomach and duodenum revealed that they shared the same histopathological and immunohistochemical characteristics as the anorectal tumor. The tumor cells were diffusely positive for S-100 protein, HMB-45, Melan-A and MITF-1 antigens. Based on these findings, the diagnosis was made of primary anorectal melanoma with secondary metastases in the upper GI tract.Conclusion: Primary anorectal melanoma is a rare aggressive malignancy with a tendency to metastasize early, due to its abundant vascular system, although metastasis to the stomach and duodenum is rare. The diagnosis of melanoma is based on the histological features and immunohistochemical stains. [ABSTRACT FROM AUTHOR]

Introduction: Although malignant melanomas (MM) are common in the head and neck region; primary malignant melanoma of the external auditory canal (EAC) is rare. Case Report: We present the case of a 50-year-old symptomatic man with a malignant melanoma of the external auditory canal, which clinically masqueraded as a haemangioma. The patient subsequently developed extensive loco-regional metastasis, requiring extensive surgery. We describe the clinical presentation, differential diagnosis, both clinical and pathological in terms of other pigmented lesions in the external auditory canal, detailed histopathology, and literature review. Conclusion: We want to emphasize the importance of immediate and adequate biopsy of any pigmented lesion in the head and neck region to rule out MM. Also, we emphasize the importance of deep biopsy for proper histopathological assessment in addition to distinguishing it from benign melanocytic nevi, in order to initiate treatment. [ABSTRACT FROM AUTHOR]

Disseminated tumor cells (DTCs) are studied as a prognostic factor in many non-hematopoietic tumors. Melanoma is one of the most aggressive tumors. Forty percent of melanoma patients develop distant metastases at five or more years after curative surgery, and frequent manifestations of melanoma without an identified primary lesion may reflect the tendency of melanoma cells to spread from indolent sites such as bone marrow (BM). The purpose of this work was to evaluate the possibility of detecting melanoma DTCs in BM based on the expression of a cytoplasmatic premelanocytic glycoprotein HMB-45 using flow cytometry, to estimate the influence of DTCs’ persistence in BM on hematopoiesis, to identify the frequency of BM involvement in patients with melanoma, and to analyze DTC subset composition in melanoma. DTCs are found in 57.4% of skin melanoma cases and in as many as 28.6% of stage I cases, which confirms the aggressive course even of localized disease. Significant differences in the groups with the presence of disseminated tumor cells (DTCs+) and the lack thereof (DTC−) are noted for blast cells, the total content of granulocyte cells, and oxyphilic normoblasts of erythroid raw cells.

Background. The malignant melanomas are the most important group of skin cancers. Although less common than the familiar basal and squamous cell tumours of the skin, they are much more frequently fatal, due to their intrinsic tendency to lymphatic and haematogenic metastasis. Objective. The article is devoted to parsing cases melanocytic tumours that were established through immunohistochemical study. Methods. In the study analyzed 236 patient material (150 women and 86 men) aged 28 to 77 years during 2010-2013 turned out to clarify the histological diagnosis of skin tumors or metastases to lymph nodes (rare at other sites). The primary monoclonal antibodies used Сytokeratin, Рan Ab1 (clone AE1/AE3), S100 (clone 4C4.9), Ki-67 (clone SP6), Vimentin (clone V9), Melanoma gp100 (clone HMB-45). Results. Naevus proliferation rate showed a statistically significant difference with respect to proliferation rate of malignant melanomas (p