North American Journal of Medicine and Science
Not a member yet
440 research outputs found
Sort by
An Unusual Case of Invasive Carcinoma with Squamous and Low-Grade Glandular Features Arising in a Giant Condyloma Acuminatum
Get PDFWe report an unusual case of invasive carcinoma with both squamous and glandular features arising in a giant anorectal condyloma acuminatum (GCA). The challenging part in rendering a definite diagnosis was the presence of a glandular component, its differentiation from other entities with similar histomorphology and low-grade human papilloma virus (HPV) expression in tumor cells. A 70-year-old woman presented with long standing symptoms of rectovaginal bleeding and recurrent perianal fistulas. She underwent an end-colostomy and later, an abdominoperineal resection. A large anorectal tumor was identified with associated invasive carcinoma showing both squamous and low-grade glandular features. The tumor recurred as pelvic mass within 6 months requiring chemoradiation therapy. The abdominoperineal resection specimen showed a large (> 5cm) verrucous mass at anorectal junction with an endophytic component invading vaginal fistulas and adjacent soft tissue. Histologically, the exophytic tumor had condylomatous proliferation with koilocytosis. The endophytic part showed invasive carcinoma with both squamous and low-grade glandular features. The glandular component was positive for CK7 and negative for CK20 and CDX-2, suggesting anal gland origin rather than a colorectal primary. High-risk HPV and p16 were both negative. In-situ hybridization (ISH) demonstrated low-grade HPV in tumor cells. GCA, also known as Buschke-Lowenstein tumor, occurs mostly in men and rarely transforms to invasive squamous cell carcinoma. Our female patient presented with recurring perianal fistulas and bleeding without detection of a condylomatous mass until after radical surgery. In addition, GCA associated with this particular pattern of squamous cell carcinoma (one with a glandular component) is exceedingly rare. The differential diagnoses included mucoepidermoid carcinoma, adenosquamous carcinoma and squamous cell carcinoma with mucinous microcystic pattern. The presence of low-risk HPV on ISH test, not only in the condyloma but also in the squamous and glandular cells of the invasive carcinoma, raises a question of its impact in tumor progression from condyloma to squamous as well as glandular invasive carcinoma. Besides being a diagnostic challenge, the clinical implication of this finding remains to be determined.
[N A J Med Sci. 2025;18(1):013-017. DOI: 10.7156/najms.2025.1801013
Sclerosing Mucoepidermoid Carcinoma with Eosinophilia of the Parotid Gland: A Case Report and Review of the Literature
Get PDFSclerosing mucoepidermoid carcinoma with eosinophilia (SMECE) is an extremely rare malignant tumor in the salivary gland. In this case, the patient is a 41-year-old male with no significant history who presented a slowly growing right neck mass. The ultrasound revealed a 3.7 cm complex cystic mass in the right parotid. The surgery was pursued after a non-diagnostic fine needle aspiration. Grossly, the tumor was a 3 cm tan nodule with minimal attached soft tissue. Microscopically, the tumor is relatively well demarcated with anastomosing lobules of neoplastic cells with fibrotic stroma rich in lymphoplasmacytosis and eosinophils. Focal glandular differentiation was highlighted by mucicarmine stain. Immunohistochemically, the tumor cells are diffuse positive for pancytokeratin and p40, while negative for S100, CD45, CD3 and CD20. The tumor is negative for MAML2, EWSR1, and FUS rearrangements. The diagnosis of this case is challenging because the tumor is obscured by the marked fibroinflammatory background. Our findings indicated an exceptionally rare malignant tumor in the parotid that may be clinically and pathologically misdiagnosed as other conditions.
[N A J Med Sci. 2025;18(1):021-023. DOI: 10.7156/najms.2025.1801021]
Key Words: sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE), parotid gland carcinom
Extranodal Rosai-Dorfman Disease in the Left Bulbar Conjunctiva: A Rare Case Report
Get PDFRosai-Dorfman disease (RDD) is a non-Langerhans histiocytosis characterized by accumulation of S100-positive foamy histiocytes, frequently demonstrating emperipolesis within lymph nodes or extranodal tissues. Extranodal disease is reported in 43% of cases. We present a case of a healthy 11-year-old male with a non-mobile, rapidly enlarging 1.5 cm mass in the medial canthal area of his left superonasal bulbar conjunctiva, and a 3.5 cm firm rubbery left neck mass. The patient denied any eye, neck, or weight loss symptoms. CMV, EBV, and bartonella antibody tested negative. Imaging report was noncontributory. Flow cytometry showed no evidence of lymphoproliferative neoplasm. The left conjunctival excision revealed histiocytic disorder of non-Langerhans cell type with xanthomatous changes. Immunostains showed positive CD20, PAX5, CD3, S100, CD68, CD163, FXIIIA, lysozyme, and fascin. Immunostains for CD1a, BRAF V600E, and ALK-1 were negative. It was clinically indeterminate whether the two masses involved an intraorbital malignant process with metastatic disease to the cervical lymph nodes, Hodgkin lymphoma, or an infectious etiology. In addition, S100 positivity is nonreactive in most cases of juvenile xanthogranuloma and does not rule out the diagnosis. Lymph node resection confirmed sinus histiocytosis with massive lymphadenopathy favoring RDD, histologically consistent with the conjunctival mass.
[N A J Med Sci. 2025;18(1):049-051. DOI: 10.7156/najms.2025.1801049]
Key Words: Rosai-Dorfman Disease, non-Langerhans cell histiocytosis, sinus histiocytosis
with massive lymphadenopathy, lymph node, ophthalmic, conjunctiva, pediatric
A Case Report of BAP1-inactivated Melanocytoma with Discussion of Possible Dual Roles of BAP1 Loss in Tumorigenesis
Get PDFBRCA1-associated protein (BAP1) is a tumor suppressor involved in a myriad of cellular processes. BAP1-inactivated melanocytomas (BIMs) are rare melanocytic tumors characterized by the loss of nuclear expression of BAP1. Here, we report a case of a 33-year-old female presenting with a cutaneous macule on the left lateral nasal wall. Histopathological examination revealed a dermal-based melanocytic neoplasm comprised of large epithelioid melanocytes with pleomorphic nuclei, some with multinucleation. Due to the morphology atypia, melanoma was suspected. However, PRAME (PReferentially expressed Antigen in MElanoma) immunohistochemical staining was negative, and further BAP1 staining showed loss of nucleus expression. Chromosomal microarray confirmed the loss of chromosome 3 (including BAP1) and chromosome X. Compared with malignant melanoma, most BIMs follow indolent courses. We further discussed the possible molecular pathogenesis of BIMs and propose that although the loss of BAP1 predisposes melanocytes to form tumor, it may hinder the development of more malignant forms. Hence, BAP1 may emerge as an interesting target for exploring synthetic lethality to better understand melanoma pathogenesis. [N A J Med Sci. 2025;18(1):009-012. DOI: 10.7156/najms.2025.1801009]
Key Words: BRCA1-associated protein (BAP1), BAP1-inactivated melanocytomas (BIMs), tumorigenesi
Impact of Culture and Traditional Dietary Habits on Gastric Cancer Carcinogenesis in East Asia
Get PDFGastric cancer is one of the most common and deadly malignant neoplasms. Its incidence significantly varies by region. Most cases of newly diagnosed gastric cancer were reported in East Asian countries where there are unique cultures and traditional dietary habits. Culture affects eating habits and influences dietary choices. People in East Asia traditionally have high salt consumption rates and eat many salt-preserved foods/pickled foods, which have been well described as important risk factors in the carcinogenesis of gastric cancer. High dietary salt intake directly damages gastric tissue, facilitates colonization by Helicobacter pylori (H. pylori) infection, and amplifies the activity of bacterial virulence factors such as CagA, thereby accelerating carcinogenesis. In East Asian countries, the incidence of H. pylori infection is significantly higher. Studies demonstrated that dietary habits correlated significantly with H. pylori infection. Recent molecular evidence suggests that H. pylori plays a significant role in the initiation and development of gastric cancer. The roles of miRNA dysregulation and signaling pathway alterations has also played a role in the carcinogenesis of gastric cancer. The interplay of diet, culture, and microbial infection underscores the importance of modifiable risk factors in shaping gastric caner outcomes. Recognizing these patterns provides a foundation for prevention strategies and public health policies tailored to the particularly high-risk populations of East Asia. [N A J Med Sci. 2025;18(1):032-037. DOI: 10.7156/najms.2025.1801032]
Key Words: Culture, Tradition, Dietary habit, East Asia, Gastric cance
Establishing the First Diagnosis of Hepatocellular Carcinoma in Lung Biopsy in a 47-Year-Old Man: A Case Report
Get PDFHepatocellular carcinoma (HCC) is a primary tumor of the liver. The most common metastatic sites include lung, lymph node, and bone. The diagnosis of HCC is usually through radiological examination and liver biopsy. The first diagnosis of HCC through a metastatic site is very rare. Here, we report a case that the first diagnosis of HCC was not through liver biopsy, but rather by a lung biopsy. The patient was a 47-year-old man with elevated AFP level. Abdominal CT and MRI showed liver nodules and lung nodules. A liver biopsy was performed, showing cirrhotic liver with extensive fibrosis. No malignancy can be identified. A lung biopsy was performed. Microscopic examination showed abundant polygonal cells with eosinophilic cytoplasm forming trabecular pattern with endothelial wrapping. These cells are positive for HepPar-1, and focally positive for Glypican-3, and negative for CK7, CK20, TTF-1, Napsin A, synaptophysin and chromogranin, consistent with metastatic hepatocellular carcinoma. The negative staining results of PAX-8, CD10, and EMA do not support differential diagnosis of metastatic renal cell carcinoma. This case raises the awareness that the first diagnosis of HCC can be through a metastatic site, especially when well-differentiated HCC is difficult to distinguish from benign hepatic masses, such as macroregenerative nodules, adenoma, or focal nodular hyperplasia. [N A J Med Sci. 2025;18(1):005-008. DOI: 10.7156/najms.2025.1801005]
Key Words: Hepatocellular carcinoma (HCC), well-differentiated HCC, immunohistochemistry, Glypican-3, HepPar-
Clear Cell Carcinoma Arising from Endometriosis in a C-section Scar: A Case Report with Literature Review
Get PDFEndometriosis is a frequent benign disorder. Malignancy arising in association with endometriosis mainly includes endometrioid carcinoma (70%), sarcoma (25%) and clear cell carcinoma (5%). The incidence rate of abdominal surgical scar endometriosis is between 0.03% and 1.08% of women undergoing pelvic surgery. Malignant transformation arising on the background of scar endometriosis is extremely rare.
Here, we report a case of clear cell carcinoma arising from endometriosis in a cesarean section scar in a 48-year-old woman. The patient presented to the emergency department with a palpable abdominal mass and constipation. A CT scan revealed a mass in the infraumbilical suprapubic rectus abdominis muscle region at the site of a cesarean section scar. A biopsy of this mass revealed an epithelioid neoplasm with papillary features, which is positive for AE1/AE3, PAX-8, and Napsin, suspicious for malignancy of gynecologic or upper urinary tract origin. The patient underwent an exploratory laparotomy, abdominal wall resection and reconstruction, and total abdominal hysterectomy with bilateral salpingo-oophorectomy. The resulting specimen included a 13.7 x 10.0 x 7.0 cm portion of red-yellow muscle and adipose tissue from the abdominal wall. Microscopic examination showed clear cell carcinoma arising from endometriosis in a cesarean section scar. ER, PR, and FOLR1 are all negative, compatible with the diagnosis. There was also metastasis to 6 out of 14 total lymph nodes submitted. The omentum, appendix, uterus, ovaries, fallopian tubes, and cervix were all benign, with the uterus containing a disordered and proliferative endometrium.
Although clear cell carcinoma arising from malignant transformation of endometriosis in the abdominal wall after cesarean section is extremely rare, for a female patient with a history of gynecologic or obstetric surgery, developing an abdominal wall mass, the possibility of a primary malignancy arising from endometriosis should be considered in the differential diagnosis. A tissue biopsy with histological evaluation and ancillary studies should be performed to ensure early detection of malignancy with proper next step treatment. [N A J Med Sci. 2025;18(1):018-020. DOI: 10.7156/najms.2025.1801018]
Key Words: Endometriosis, Malignant Transformation, Clear Cell Carcinoma, Abdominal Wall Sca
A Rare Case of Lingual Cryptococcosis Presented as An Tongue Nodule in A HIV-Positive Patient
Get PDFCryptococcus is an opportunistic fungal infection that primarily affects those with advanced HIV/AIDS. Oral manifestations are rare, and involvement of the tongue is exceptionally uncommon. Here, we present a rare case of lingual cryptococcosis in a 30-year-old male, who underwent treatment for cryptococcal meningitis presented with a papillary-like mass on the tongue. Given his history of advanced HIV and former smoking, oral malignancy or infection was initially considered. A subsequent biopsy of the tongue nodule collected firm tan soft tissue fragments. Histologic evaluation of the mass on H&E staining revealed squamous epithelium with subepithelial tissue containing round to oval yeasts with thick mucoid capsules, amidst mild inflammation. Focal ulceration and bacterial colonies were present on the epithelial surface. No evidence of malignancy can be identified. Periodic Acid-Schiff (PAS) and Grocott Methenamine Silver (GMS) stains highlighted abundant fungal organisms. Mucicarmine decorated the highly characteristic gelatinous capsules with bright pink color, consistent with cryptococcosis. This rare case of disseminated cryptococcosis involving the tongue in an HIV-positive patient highlights the need to consider fungal infections in atypical oral lesions. Oral cryptococcosis is uncommon and can easily be mistaken for more common conditions, such as neoplasms or bacterial infections. Our findings underscore the importance of considering fungal infections in the differential diagnosis of atypical oral lesions in immunocompromised patients and reinforce the role of biopsy in guiding timely diagnosis and management.
[N A J Med Sci. 2025;18(1):024-027. DOI: 10.7156/najms.2025.1801024]
Key Words: Cryptococcus, Cryptococcosis, HIV, tongue, mucicarmine stai
Fumarate Hydratase-deficient Uterine Leiomyoma in a 25-Year-Old Woman
Get PDFFumarate hydratase (FH) is an essential enzyme in the citric acid (Krebs) cycle. Genetic mutations in the FH gene can contribute to tumor development. FH-deficient uterine leiomyoma is a rare subtype of uterine leiomyoma, accounting for approximately 0.4–1.6% of all uterine leiomyomas. It can occur in both syndromic and sporadic settings. Germline mutations in FH are associated with hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome, which presents with cutaneous and uterine leiomyomas and an aggressive form of renal cell carcinoma (RCC). Identifying FH-deficient uterine leiomyomas may facilitate early detection of patients at risk for RCC. Here, we present a case of a 25-year-old woman, gravida 0, had pelvic pain, dyspareunia, and heavy menstrual bleeding, significantly affecting her daily activities. Pelvic MRI revealed a 3.5 cm intramural fibroid in the posterior uterine wall. The patient opted for myomectomy. The surgical specimen consists of multiple tan, nodular, rubbery tissue fragments, including one large 4 cm nodule and several smaller nodules (0.4–1.3 cm). Sectioning shows whorled cut surface without hemorrhage or necrosis. Microscopically, the tumor exhibited spindle and epithelioid cell proliferation, alveolar edema, and staghorn/hemangiopericytoma-like vessels. Tumor cells also displayed ovoid nuclei with eosinophilic nucleoli and bizarre nuclei. Rhabdoid /eosinophilic cytoplasmic inclusions are present. Immunohistochemical analysis showed positivity for smooth muscle actin and desmin, confirming smooth muscle differentiation. The tumor was negative for FH and positive for S-(2-succino) cysteine (2SC). The diagnosis of FH-deficient leiomyoma was rendered based on these histological findings and confirmed by loss of FH expression on immunostaining. The negative FH and positive 2SC indicate biallelic FH inactivation. Genetic counseling was recommended to rule out germline FH mutations and HLRCC syndrome. Through this case report, we want to raise awareness that an early-onset large leiomyoma with bizarre nuclei needs to consider the possibility of FH-deficient uterine leiomyomas to facilitate early detection of patients at risk for RCC. [N A J Med Sci. 2025;18(1):028-031. DOI: 10.7156/najms.2025.1801028]
Key Words: fumarate hydratase-deficient, leiomyoma, hereditary
leiomyomatosis and renal cell carcinoma (HLRCC) syndrom
Molecular Biology of Thyroid Cancer and Their Clinical Applications
Get PDFThyroid cancer is the most common endocrine malignancy, with papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) being the predominant subtypes. Recent advancements in molecular biology have significantly improved our understanding of thyroid carcinogenesis, leading to novel diagnostic and therapeutic strategies. Key genetic alterations, including BRAF, RAS, RET/PTC fusions, and PAX8-PPARγ rearrangements, play crucial roles in tumor initiation and progression. BRAF mutations, particularly BRAFV600E, are strongly associated with aggressive PTC phenotypes, whereas RAS mutations are prevalent in follicular-patterned thyroid tumors. Poorly differentiated and anaplastic thyroid carcinomas harbor mutations in TP53, TERT promoter, and components of the MAPK and PI3K pathways, contributing to their aggressive behavior. Advances in molecular diagnostics, such as next-generation sequencing and gene expression classifiers, have enhanced the accuracy of thyroid nodule evaluation, reducing unnecessary surgeries. This review provides an in-depth analysis of the molecular mechanisms underlying thyroid cancer and their clinical applications, emphasizing the role of molecular testing in risk stratification, prognostication, and personalized treatment approaches.
[N A J Med Sci. 2025;18(1):038-048. DOI: 10.7156/najms.2025.1801038]
Key Words: Molecular biology, thyroid cancer, RET, RAS, BRAF, clinical application