Potential diagnostic utility of PRAME and p16 immunohistochemistry in melanocytic nevi and malignant melanoma.

BACKGROUND: PRAME (PReferentially expressed Antigen in MElanoma) is a tumor-associated antigen that has been studied in various cutaneous melanocytic lesions. p16, on the other hand, has been proposed to aid in distinguishing between benign and malignant melanocytic neoplasms. Studies on the diagnostic utility of PRAME and p16 in combination in differentiating nevi from melanoma are limited. We aimed to assess the diagnostic utility of PRAME and p16 in melanocytic tumors and their role in distinguishing between malignant melanomas and melanocytic nevi. METHODS: This is a single-center retrospective cohort analysis over a 4-year period (2017-2020). We used the pathological database of malignant melanomas (77 cases) and melanocytic nevi (51 cases) specimens from patients who underwent shave/punch biopsies or surgical excisions and evaluated immunohistochemical staining percentage positivity and intensity for PRAME and p16. RESULTS: Most malignant melanomas showed positive/diffuse PRAME expression (89.6%); on the other hand, 96.1% of nevi did not express PRAME diffusely. p16 was expressed consistently in nevi (98.0%). However, p16 expression in malignant melanoma was infrequent in our study. PRAME had a sensitivity and specificity of 89.6% and 96.1%, respectively, for melanomas versus nevi; on the other hand, p16 had a sensitivity and specificity of 98.0% and 28.6%, respectively, for nevi versus melanoma. Also, a PRAME+/p16- melanocytic lesion is unlikely to be a nevus where most nevi were PRAME-/p16+. CONCLUSION: In conclusion, we confirm the potential utility of PRAME and p16 for distinguishing melanocytic nevi from malignant melanomas.

PIK3R1, HRAS and AR Gene Alterations Associated with Sclerosing Polycystic Adenoma of the Parotid Gland.

Sclerosing polycystic adenoma (SPA) is a rare neoplasm occurring in the salivary glands, mainly the parotid gland. Although it was originally thought to represent a non-neoplastic process, recent genetic data have proven its monoclonality, supporting its neoplastic origin. We report a case of a 73-year-old woman who presented with left neck swelling and pain. A 3 cm hypoechoic, heterogeneous, solid mass was identified on neck ultrasonography within the left parotid gland. Fine needle aspiration revealed benign acinar cells and lymphocytes. Left partial superficial parotidectomy was performed and a diagnosis of SPA was made. Targeted next-generation sequencing (NGS) revealed three clinically significant alterations in the PIK3R1, HRAS, and AR genes. Alterations in the PIK3R1 gene have been previously reported in cases of SPA; however, this study is the first to report two novel clinically significant genomic alterations in the HRAS and AR genes. AR protein expression by immunohistochemistry was strongly and diffusely positive in the neoplastic epithelial cells compared to the adjacent normal salivary gland tissue, which was dead negative for AR. This molecular profile will enhance our understanding of the molecular pathways underlying the development of this tumor. Although this entity was initially thought to be a reactive process, evidence from our case and similar cases strongly support the notion that it is neoplastic due to the presence of specific genetic alterations linked to it.

CD63 expression in metastatic melanoma and melanocytic nevi in lymph nodes.

Lymph node status remains one of the most important determinants for prognosis in patients with invasive malignant melanoma. Immunohistochemical stains are routinely employed in the histopathologic evaluation of sentinel lymph nodes removed for staging in patients with melanoma. Histologic analysis may reveal the presence of incidental benign melanocytic nevus cell inclusions (BMNCI), which are critical to distinguish from metastatic melanoma (MM). Our study assesses the utility of NK1 C3 (CD63) immunohistochemical staining in distinguishing between MM and BMNCI in sentinel lymph nodes. We found no difference in staining of MM and BMNCI, precluding its usefulness in differentiating between benign and malignant melanocytes. Thus CD63 lacks specificity when facing challenging cases requiring distinction between benign and malignant melanocytic cells; however, in combination with other immunohistochemical antibodies, CD63 may be useful in supporting melanocytic differentiation. Distinguishing MM and BMNCI continues to be a diagnostic challenge at times. Further research is needed to identify potentially useful markers to provide better diagnostic utility when evaluating lymph node biopsies in patients with melanoma.

Nanotherapeutic approach to treat diabetic foot ulcers using tissue-engineered nanofiber skin substitutes: A review.

BACKGROUND AND AIMS: Diabetes mellitus (DM) is a chronic metabolic disease associated with long-term multisystem complications, among which nonhealing diabetic foot ulcers (DFUs) are recognized as major cause of morbidity and mortality. Treating DFUs with surgical procedures such as synthetic or biological skin grafts or skin substitutes has several limitations, where none of the currently available skin substitutes is ideal. METHODS: OVID/Medline and PubMed databases were searched using the Medical Subject Heading (MeSH) or Title/Abstract words ("diabetic foot ulcers", "skin substitutes", and "nanofibers"), to identify published research studies on DFUs and nanofibers. RESULTS: Electrospinning nanotechnology is being used in the biomedical field to produce polymeric nanofibers impregnated with drugs for wound healing, burns and diabetic ulcers. Those nanofibers also enable seeding of cells into them and culturing them in vitro to synthesize tissue-like structures. Knowing the advantages of generating patient-specific induced pluripotent stem cells (iPSCs) and organoids in three-dimension (3D), including skin organoids, it is worth mingling these technologies to develop tissue-engineered biological skin substitutes. CONCLUSION: Nanofiber-skin substitutes hold promise for treatment of patients suffering from DFUs and inspire novel strategies that could be applied to other organ systems as well, introducing a new era of "regenerative and personalized medicine".

Normal Expression of SRY-related HMG-BOX Gene 10 (SOX-10) in Recent and Old Cutaneous Scars is a Potential Mimicker of Desmoplastic Malignant Melanoma.

Desmoplastic malignant melanoma (DMM) is an amelanotic spindle cell proliferation that can be mistaken for a cutaneous scar. The distinction can be difficult in reexcisions because DMM is negative for conventional melanoma markers such as HMB-45 and Melan-A, and scars may be positive for S-100 protein and SOX-10. We compare a total of 12 DMM cases with 8 reexcision and 35 old non-reexcision cutaneous scars using SOX-10 immunohistochemical stains. Cell quantification was performed on captured images using ImageJ 1.51t. SOX-10 was expressed in DMM (100%, 12/12), and reexcision (75%, 6/8), atrophic (88%, 22/25), hypertrophic (100%, 8/8), and keloid-type (100%, 2/2) scars. The cellular density of SOX-10 positive cells in DMM (822.9±116.9 cells/mm, mean±SEM) was significantly higher than in any scar subgroup (hypertrophic: 188.4±20.40 cells/mm, atrophic: 83.78±11.13 cells/mm, reexcision: 96.72±30.13 cells/mm, P<0.0001). Hypercellular areas in reexcision scars showed dense positivity as hypocellular areas in DMM (upper limit for scars: 258.42 positive cells/mm vs. lower limit for DMM: 292.42 positive cells/mm). SOX-10 positive cells in scars are predominantly monomorphic and small following the overall directionality of the tissue. In contrast, DMM cells exhibited enlarged atypical nuclei with a haphazard distribution, invasion as single cells or in clusters, and tropism for adnexal structures (58%) and neurovascular bundles (67%). In conclusion, cutaneous scars contain SOX-10 positive cells. The evaluation of residual DMM needs careful attention to morphologic characteristics to avoid over-interpretation of SOX-10 immunostains.

A Case of Isolated Primary Pleural Neurofibroma in a 39-Year-Old Woman.

Primary benign neurogenic neoplasms of the pleura are exceedingly rare. Neurofibromas rarely involve the pleura. A review of the literarture reveals only a single reported case of isolated pleural neurofibroma. Herein the authors describe another case of isolated primary pleural neurofibroma. A 39-year-old nonsmoker woman presented to the emergency room with complaints of progressively worsening chest pain of one month duration. A computed tomography of the chest revealed a crescent shaped, pleural based mass suspicious for a neurogenic tumor such as an intercostal schwannoma. A PET-CT skull base to midthigh failed to reveal any other masses or abnormalities. A surgical excision of the mass was performed due to the patient's intractable pain. The resected specimen consisted of an ovoid fragment of soft tissue with pale yellow, smooth and glistening cut surface. Microscopic examination revealed the tumor to be composed of spindle cells with wavy nuclei arranged haphazardly in loose collagenous and pale myxoid stroma with rare interspersed mast cells. The spindle cells were diffusely positive for S100 protein and SOX-10, and focally positive for neurofilament. In the absence of any other masses in the patient and no pertinent history, a diagnosis of primary pleural neurofibroma was made. This case emphasizes the need to consider neurofibroma in any spindle cell neoplasm of the pleura irrespective of age or singularity.

Spontaneous perforation of small intestine followed by rupture of the cystic artery: the natural history of Vascular Ehlers-Danlos Syndrome.

Vascular Ehlers-Danlos Syndrome (VEDS) is a rare autosomal dominant disorder caused by mutations in the COL3A1 or COL1A1 genes. Its mortality is secondary to sudden and spontaneous rupture of arteries or hollow organs. The genotype influences the distribution of arterial pathology with aneurysms of intra-abdominal visceral arteries being relatively uncommon. We describe the case of a young man with probable VEDS who died of a spontaneous rupture and dissection of the cystic artery. The patient initially presented with abdominal pain due to an unrecognized spontaneous perforation of the small intestine complicated by sepsis. We postulate that inflammatory mediators may have triggered the arterial rupture due to remodeling and weakening of vessel walls. The phenotype of the patient's vascular damage included bilateral spontaneous carotid-cavernous sinus fistulae and dissection with pseudoaneurysm formation of large- and medium-sized arteries, predominantly the abdominal aorta and its branches. The autopsy uncovered a long history of vascular events that may have been asymptomatic. These findings along with a positive family history supported the VEDS diagnosis. Loeys-Dietz, Marfan, and familial thoracic aortic aneurysm and dissection syndromes were ruled out based on the absence of arterial tortuosity, eye abnormalities, bone overgrowth, and the distribution of vascular damage among other features. Interestingly, microscopic examination of the hippocampus revealed a focus of neuronal heterotopia, commonly associated with epilepsy; however, the patient had no history of seizures. The natural course of VEDS involves the rupture and dissection of arteries that, if unrecognized, can lead to a rapid death after bleeding into free spaces.

Spontaneous perforation of small intestine followed by rupture of the cystic artery: the natural history of Vascular Ehlers-Danlos Syndrome

Vascular Ehlers-Danlos Syndrome (VEDS) is a rare autosomal dominant disorder caused by mutations in the COL3A1 or COL1A1 genes. Its mortality is secondary to sudden and spontaneous rupture of arteries or hollow organs. The genotype influences the distribution of arterial pathology with aneurysms of intra-abdominal visceral arteries being relatively uncommon. We describe the case of a young man with probable VEDS who died of a spontaneous rupture and dissection of the cystic artery. The patient initially presented with abdominal pain due to an unrecognized spontaneous perforation of the small intestine complicated by sepsis. We postulate that inflammatory mediators may have triggered the arterial rupture due to remodeling and weakening of vessel walls. The phenotype of the patient's vascular damage included bilateral spontaneous carotid-cavernous sinus fistulae and dissection with pseudoaneurysm formation of large- and medium-sized arteries, predominantly the abdominal aorta and its branches. The autopsy uncovered a long history of vascular events that may have been asymptomatic. These findings along with a positive family history supported the VEDS diagnosis. Loeys-Dietz, Marfan, and familial thoracic aortic aneurysm and dissection syndromes were ruled out based on the absence of arterial tortuosity, eye abnormalities, bone overgrowth, and the distribution of vascular damage among other features. Interestingly, microscopic examination of the hippocampus revealed a focus of neuronal heterotopia, commonly associated with epilepsy; however, the patient had no history of seizures. The natural course of VEDS involves the rupture and dissection of arteries that, if unrecognized, can lead to a rapid death after bleeding into free spaces.

Massive Lipomatosis of the Small Intestine Causing Intussusception.

Lipomatosis is a rare condition characterized by diffuse, unencapsulted adipose tissue deposition. Intestinal involvement is rare, and presentation as intussusception is rarer still. We report a 40-year-old man who presented with abdominal pain and fecal urgency. Abdominal CT scan showed a protuberant ileo-cecal valve, with intussusception of the ileum into the cecum. The mucosal surface of the resected bowel was bulbous and protuberant, showing loss of mucosal folds, and there was an 8 × 5 × 5 cm mass prolapsing into the ileo-cecal valve. Microscopically there was abundant adipose tissue in the submucosa with an unremarkable mucosa. The patient recovered uneventfully with only occasional cramping in the left abdomen.

Liposarcoma in the Inguinal Canal: Challenges in Preoperative Diagnosis and Importance of Routine Pathological Examination of "Hernia Sacs".

Liposarcoma is the most common histologic subtype of soft tissue sarcoma in the retroperitoneum. The distinction of primary cord liposarcomas, which arise in and are confined to the inguinal canal, from inguinoscrotal extension of a retroperitoneal tumor is mandatory. Both can be found incidentally in inguinal hernia sac specimens. Preoperative diagnosis is essential for adequate surgery with clear margins. We present a clinicopathological correlation of two men with slowly growing right para-testicular masses diagnosed as inguinal hernias. Pathological examination revealed well-differentiated lipoma-like liposarcoma and well-differentiated liposarcoma mixed type (lipoma-like and sclerosing types), respectively. The first tumor was considered a primary cord liposarcoma with no recurrence on follow-up. The second tumor showed an unusual growth pattern of discontinuous nodules that gave the false impression of complete resection. This growth pattern may explain why inguinal liposarcomas have a high recurrence rate despite apparently negative surgical margins. A follow-up CT scan exposed a fatty tumor in the retroperitoneum of the second patient. Careful interpretation of imaging studies in patients with fatty inguinal masses is mandatory to rule out a retroperitoneal or intraperitoneal component. Although the two cases herein discussed represent less than 0.1% of the total inguinal hernia sacs examined over the past five years in our pathology department, we recommend routine examination of all "mass-containing" hernia sacs as missing the diagnosis of liposarcoma can lead to substantial morbidity and mortality.

Disseminated Kaposi sarcoma with epithelioid morphology in an HIV/AIDS patient: A previously unreported variant.

Kaposi sarcoma is an oligoclonal HHV-8-driven vascular proliferation that was first described by a Viennese dermatologist Dr Moritz Kaposi. The disease has been seen in different clinical-epidemiological settings with a wide morphologic spectrum. We report a 52-year-old Caucasian man with HIV/AIDS and Kaposi sarcoma who presented with dyspnea and pleural effusion. He reported numerous tender subcutaneous nodules developing over the past few months on his chest, back and abdomen. An excisional biopsy of one of the nodules was performed. Touch preps revealed malignant cells in clusters. Microscopically, the neoplasm appeared undifferentiated with an epithelioid morphology, and involved the dermis and subcutaneous fat. Despite the medical history, Kaposi sarcoma was not considered foremost in the differential diagnosis. The malignant cells were positive for vimentin and negative for S100 protein, keratin AE1/3, CK7, CK20, napsin A, TTF-1 and synaptophysin. Additional stains revealed positivity for HHV-8, CD31 and D2-40, supporting the diagnosis of Kaposi sarcoma. Kaposi sarcoma has been well described with many variants that may cause diagnostic difficulty. An epithelioid variant has not been reported and consequently, may cause misinterpretation of an otherwise well-known entity that may become life threatening if appropriate treatment is not initiated in a timely manner.

Is the routine microscopic examination of proximal and distal resection margins in colorectal cancer surgery justified?

Microscopic examination of the proximal and distal resection margins is part of the routine pathologic evaluation of colorectal surgical specimens removed for adenocarcinoma. Anastomotic donuts are frequently received and microscopically examined. We examined 594 specimens received over a period of 10 years and found only 3 cases of definitive direct involvement of a longitudinal margin by carcinoma. All 3 cases also showed tumor at the margin grossly. One case of margin involvement by adenocarcinoma was found in which the tumor was grossly 1.7 cm away; however, this finding was likely a tumor deposit, as the patient had diffuse metastatic disease. All 242 anastomotic donuts examined were free of carcinoma. Our study suggests that the proximal and distal margins of colorectal cancer specimens need not be examined microscopically in order to accurately assess margin status in cases where the tumor is at least 2 cm away from the margin of resection. Also, in cases in which anastomotic donuts are included with the case, these should be considered the true margins of resection and may be microscopically examined in place of the bowel specimen margins when margin examination is needed. Anastomotic donuts need not be examined if the tumor is more than 2 cm away from the margin. An exception to this rule would be cases of rectal adenocarcinoma where neoadjuvant therapy is given prior to surgery. In these cases, mucosal evidence of malignancy may be absent and microscopic examination of the margins is the only way to assure complete excision.

Can SOX-10 or KBA.62 Replace S100 Protein in Immunohistochemical Evaluation of Sentinel Lymph Nodes for Metastatic Melanoma?

BACKGROUND: Microscopic evaluation of sentinel lymph nodes for metastatic melanoma relies, in part, on the use of immunohistochemical analysis to identify minute metastatic deposits that may be overlooked on routine microscopy. At present S100 protein is widely used in this role, in large part for its superior sensitivity; however, interpretation is hampered by the presence of benign S100 protein-positive cellular elements present in every lymph node, leading to reduced specificity and consequent difficulties in interpretation. In recent years, multiple melanocytic markers have emerged that promise superior sensitivity and specificity, including KBA.62 and SOX-10. SOX-10 shows a nuclear pattern of staining. In normal tissue it is expressed in Schwann cells, melanocytes, and myoepithelial cells of salivary, bronchial, and mammary glands. KBA.62 is also specific except for staining of endothelial cells and shows a membranous staining pattern. This study was undertaken to determine whether KBA.62 or SOX-10 could equal (or surpass) the sensitivity of S100 protein while offering superior specificity in the immunohistochemical evaluation of sentinel lymph nodes for metastatic melanoma. DESIGN: In this study we performed immunohistochemical stains for S100 protein, Sox-10, and KBA.62 on 50 lymph nodes with proven metastatic melanoma. RESULTS: SOX-10 detected all cases of metastatic melanoma (50 of 50 cases; 100%) compared with S100 protein (48 of 50 cases; 96%) and KBA.62 (37 of 50 cases; 74%). There was no "background" staining of normal cellular elements with SOX-10 or KBA.62. In contrast, S100 protein was expressed in scattered dendritic interdigitating reticulum cells in the paracortex of lymph nodes, showing cytoplasmic and nuclear positivity, sometimes posing significant difficulty in differentiating benign reticulum cells from single cell metastatic melanoma. CONCLUSIONS: Our findings suggest that SOX-10 may be superior to S100 protein for identifying metastatic melanoma in a lymph node. KBA.62 was less sensitive than either marker, although more specific than S100 protein.

Pityriasis rosea-like cutaneous eruption as the presenting symptom of Hodgkin lymphoma. Case report and review of the literature.

BACKGROUND: Cutaneous involvement by Hodgkin lymphoma is extremely rare and usually follows extensive involvement of the lymph nodes. Cutaneous manifestations of Hodgkin lymphoma may be divided into specific and non-specific. Generalized pruritus is one of the most common non-specific presentations of Hodgkin lymphoma as is cutaneous granulomas. Such signs and symptoms should prompt thorough physical exam, including evaluation of lymph nodes, especially in a young patient. MAIN OBSERVATION: We report a case of a 22-year-old man who presented with night sweats, weight loss, dry cough, and generalized maculopapular eruption that started with a large patch in the center of the chest and spread to the extremities. Biopsy of the rash revealed pityriasis rosea-like findings. A computerized tomography scan of the chest revealed a mediastinal mass. Biopsy of the mediastinal mass revealed Reed-Sternberg cells in a fibrotic background, diagnostic of Hodgkin lymphoma, nodular sclerosis type. CONCLUSION: In conclusion, the presentation of Hodgkin lymphoma as a pityriasis rosea-like cutaneous eruption is rare and clinicians should be aware of this presentation. In this paper we review the non-specific cutaneous manifestations of Hodgkin lymphoma in an effort to raise awareness of the diversity of early cutaneous signs of Hodgkin lymphoma.

Allantoic, vitelline, and "hybrid" embryonic vestiges of the umbilical cord: an immunohistochemical study.

The embryonic origin of umbilical cord vestiges is well documented; however, their immunophenotype is unknown. This study was conducted to determine whether vitelline and allantoic remnants can be differentiated using immunohistochemical markers. All allantoic remnants were stained with p63 and were negative for CDX2, whereas the vitelline remnants stained with CDX2 and were negative for p63. An unexpected finding was a small number of morphologically ambiguous cases that stained with both markers in a complimentary manner. The term "hybrid" remnant is proposed for these remnants.

IMP3 expression in serous tumors of the ovary.

Insulin-like growth factor II mRNA-binding protein (IMP3) is an oncofetal protein involved in embryogenesis, which is expressed in a variety of malignant neoplasms. It is rarely expressed in normal adult tissue and benign tumors. The aim of this study was to evaluate the expression of IMP3 in benign and malignant serous tumors of the ovary. Seventy-nine ovarian tumors were examined for IMP3 expression by immunohistochemical analysis, comprising 16 benign serous tumors, 19 borderline serous tumors, and 44 serous carcinomas. Positive staining was defined as brown staining in the cytoplasm. Negative staining was defined as absent staining or staining of <5% of tumor cells. The intensity of staining (weak, moderate, and strong) and percentage (0% to 100%) of neoplastic cells staining positive for cytoplasmic IMP3 staining were recorded in each case. Moderate to strong cytoplasmic staining for IMP3 was observed in 30 of 44 (68%) serous carcinomas of the ovary; in contrast, <5% of the borderline and benign serous tumors expressed IMP3 ranging from weak to strong cytoplasmic staining. Statistically, the difference in IMP3 expression between these groups of tumors was highly significant (P<0.0001). Our findings demonstrate moderate to strong expression of IMP3 in the majority of ovarian serous carcinomas as compared with benign/borderline serous tumors, which demonstrated weak to strong expression in a small minority (<5%) of the tumors. Thus, IMP3 may be a useful adjunctive tool in the pathologic evaluation of ovarian serous tumors.

Cutaneous drug eruptions: a 5-year experience.

BACKGROUND: The diversity of cutaneous drug eruptions encompasses many clinicopathologic entities. METHODS: Cases with a pathologic diagnosis of drug eruption from 2000 to 2005 were retrieved from our institution. The histologic slides were reviewed, the patterns of inflammatory changes were recorded, and a chart review was performed. RESULTS: The majority of the cases (94%) were "morbilliform"-type rashes. Eighty-two percent of cases exhibited an inflammatory infiltrate confined to the superficial dermis. Eighty percent exhibited a perivascular and interstitial pattern of dermal infiltrate. The infiltrate was composed of lymphocytes and eosinophils in approximately 29% of cases, lymphocytes and neutrophils in approximately 10% of cases, and lymphocytes, eosinophils, and neutrophils in approximately 21% of cases. Eosinophils were present in only 50% of cases. Approximately half (53%) of the cases exhibited epidermal-dermal interface changes. LIMITATIONS: The cases were limited to those with a pathologic diagnosis of cutaneous drug reaction, thereby excluding any cases with drug-induced disease not specifically diagnosed (histologically) as such. CONCLUSIONS: While the histologic features of most drug eruptions are not entirely specific, the finding of superficial infiltrates composed variably of lymphocytes, neutrophils, and eosinophils, either with or without interface changes, should suggest the possibility of a morbilliform drug eruption. Clinical correlation is very helpful to confirm the diagnosis. To our knowledge, this study is the most extensive documenting the histologic findings in morbilliform drug eruptions.