BACKGROUND: The erythroblastosis transformation-specific regulated gene 1 (ERG) is a transcription factor that can be used as an immunohistochemical (IHC) marker in the diagnosis and prognostication of malignancy. ERG was initially used in prostate cancer; however, it is a useful marker in extramedullary myeloid disease. Patients with acute myeloid leukemia (AML), dry bone marrow aspirate, and CD34, CD117-negative blast cells can be in a diagnostic dilemma. This audit aimed to (a) validate ERG IHC in bone marrow trephine samples, (b) quantify ERG IHC positivity in an AML cohort, and correlate concordance with CD34 and CD117 IHC, when available, and (c) to see whether ERG is a useful adjunct in the diagnosis of cases of AML.
METHODS: A retrospective audit was completed of all new and relapsed cases of AML over one year at a single center. For inclusion, patients needed a trephine specimen at presentation, and all had a hematoxylin and eosin(H&E) specimen, ERG IHC, and at least one or both of CD34 and CD117 IHC. Four pathologists independently assessed the stains quantitatively and qualitatively in comparison to the morphology seen on the H&E sample. The kappa value was used to assess agreement.
RESULTS: Seventeen patients with AML met the inclusion criteria. All specimens had H&E, CD34, and ERG stains; 9/17 (53%) had CD117 IHC. ERG demonstrated high concordance with blast cells on H&E morphology, with a high agreement among pathologists. Qualitatively, pathologists recognized that ERG spared lymphoid nodules; however, it also stained granulocytes at various maturation stages.
CONCLUSIONS: ERG is a sensitive marker for the diagnosis of AML. ERG can help visualize blast cells that have been confirmed by ancillary tests. More research into the utility of ERG in AML diagnostics is recommended.

Clinicians diagnosing malignant peritoneal epithelioid mesothelioma (MPM or MPeM) have historically had challenges due to the low incidence of the disease, as well as the often vague symptomatology that patients present with. Newer advances in technology, specifically in immunocytochemistry, have provided a clearer path to diagnosis. Additionally, malignant mesotheliomas must be differentiated from carcinomas. This is done via histology, immunocytochemistry, as well as a careful incorporation of the patient\'s clinical history. In this case, we present an asymptomatic 73-year-old non-smoker female with no past medical history of asbestos exposure. She was diagnosed with MPM following a routine abdominal hernia repair. Subsequent workup revealed a lung infiltrate that was successfully biopsied and resected, evidently found to be adenocarcinoma. A careful review of the resulting pathology, as well as the interpretation of immunocytochemistry, supported the notion that the patient had two independent malignant processes occurring at once. This case underscores the rarity of two similar, yet distinct cancers, as well as epidemiology, symptomatology, histology, immunocytochemistry, and prognosis.

Adult intussusception is an infrequent occurrence typically resulting from an identifiable lead point of a benign or malignant etiology. Here, we present a case of a 19-year-old male who presented to the emergency department with complaints of abdominal pain, intractable nausea, and fluctuations between bloody diarrhea and constipation. These symptoms had begun two months prior and had increased in severity, resulting in significant appetite changes. An abdominal and pelvic computed tomography scan without contrast was obtained, which showed evidence of intussusception of the ileocecum into the transverse colon with resultant small bowel obstruction. The patient underwent an exploratory laparotomy, which resulted in a partial ileocolectomy due to the presence of a 6.8 cm cecal mass with palpable mesenteric lymphadenopathy. The pathologic specimen was identified as Burkitt lymphoma based on a combination of histologic, immunohistochemical, and fluorescence in situ hybridization findings. Currently, the patient is undergoing three cycles of rituximab, cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate, ifosfamide, etoposide, and high-dose cytarabine (R-CODOX-M/IVAC) per Magrath protocol for low-risk Burkitt lymphoma.

OBJECTIVE: To determine the role of geminin as a tool for differentiating various types of cervical intraepithelial neoplasia (CIN) and cervical carcinoma (CC).
METHODS: Seventy women newly diagnosed with CIN or CC undergoing cervical biopsy were included; their clinical profile, human papilloma virus (HPV) positivity, and colposcopy findings were noted, and biopsy tissue was analyzed for geminin content.
RESULTS: On geminin immunohistochemistry, 100% of women with CIN3 and 96.29% of women with CC had geminin two plus or more. When analyzed as ordinal variables, there was a significant correlation (spearman\'s rho 0.35, p 0.01) between geminin and biopsy results (CIN1, CIN2, CIN3, and CC).
CONCLUSIONS: Screening tests for cervical cancer, like conventional pap smears, liquid-based pap smears, and triaging with HPV, have limitations. It is important to be able to differentiate between high-grade lesions, invasive cancer, and low-grade lesions. The detection of geminin in these cells may aid in the confirmation of the diagnosis and ensure adequate treatment. Cervical intraepithelial lesions and carcinoma cervix demonstrated a correlation between increased geminin expression in CIN1 vs. CC and CIN2 vs. CC. Geminin may be a potential surrogate marker for higher-grade cervical lesions, and further research is needed to corroborate evidence in this direction.

Epithelioid sarcoma (ES) is an uncommon soft tissue sarcoma. It is usually located in the extremities and exceptionally in the neck. Its diagnosis constitutes a real challenge which is based on histology and immunohistochemistry staining that must be interpreted with caution given the anatomopathological similarities to other tumors. In this article, we report a case of a 37-year-old man admitted for a locally advanced ES of the neck. There were suspicions of lymph node metastases of nasopharyngeal carcinoma at the first pathological examination. The patient received palliative chemotherapy and was referred to the supportive care department. Through this case, we will discuss the clinical and anatomopathological characteristics and therapeutic options of this extremely rare tumor which poses a diagnostic challenge.

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in the gastrointestinal tract and is most commonly seen in the stomach. The standard treatment for patients with advanced GISTs include both surgical resection and imatinib therapy. There have been cases that document the alterations of patients\' GIST histomorphology both with primary GIST prior to imatinib therapy and with recurrent GIST after imatinib therapy. However, there has been no documented case of a patient who has recurrent GIST with chondroid differentiation at the primary site after imatinib therapy. In this article, we report an incidental finding of a 58-year-old patient who had two treatments of imatinib therapy prior to surgical resection of her recurrent GIST in her stomach. We also explore through a mini-literature review the various cases of GIST with chondroid differentiation that have been reported to compare the histomorphology, immunophenotype, and patient demographic of these cases. This article is significant for reporting a rare finding of GIST after imatinib therapy and highlights the various presentations that GIST could acquire after imatinib therapy that exclude another malignant process, such as chondrosarcoma.

Basal cell carcinoma (BCC) is one of the most common skin malignancies worldwide. Morpheaform basal cell carcinoma (MBCC) is a rare aggressive subtype of BCC that presents with unique histologic features. Both are treated surgically and have an excellent survival rate. Metastatic breast carcinoma, on the other hand, has a poor survival rate along with a more burdensome therapeutic route including chemotherapy. Due to an overlap in common immunohistochemistry stains, there is a possibility of confusing the diagnosis of BCC with metastatic breast carcinoma resulting in potential patient harm. Therefore, a timely and accurate diagnosis distinguishing these malignancies is essential. We report a near-miss event in which a 77-year-old female with MBCC was mistakenly diagnosed with metastatic breast carcinoma. We discuss the details of these stains, characteristic features of MBCC, and treatment options and emphasize the importance of combining laboratory medicine with clinical expertise to improve patient outcomes.

BACKGROUND: The aim of this study was to detect the possible endothelial expression of embryonic-type cancer stem cells (CSC) marker SOX2 and the stemness-type CSC marker CD147 in oral potential malignant disorders (OPMDs), oral leukoplakia (OL) in particular, and oral squamous cell carcinoma (OSCC).
METHODS: This study focuses on the immunohistochemical pattern of expression of CSC protein-biomarkers SOX2 and CD147 in paraffin-embedded samples of 21 OSCCs of different grades of differentiation and 30 cases of OLs with different grades of dysplasia, compared to normal oral mucosa.
RESULTS: The protein biomarker SOX2 was expressed in the endothelial cells, but without establishing any statistically significant correlation among OSCC, OL, and normal tissue specimens. However, SOX endothelial staining was noticed in 7/30 (23.3%) cases of OL (one non-dysplastic, one mildly dysplastic, one moderately dysplastic, and four severely dysplastic cases) and 5/21 (23.8%) cases of OSCC (two well-differentiated, one moderately differentiated, and two poorly differentiated cases). Although CD147 is expressed in normal oral epithelium, OL, and OSCC neoplastic cells, its vascular-endothelial expression was noticed in only 2/5 (40%) cases of normal oral epithelium, 1/30 (3.3%) cases of OL (one severely dysplastic case), and 4/21 (19%) cases of OSCC (two well-differentiated, one moderately differentiated, and one poorly differentiated case). Therefore, no statistically significant correlation among OSCC, OL, and normal tissue specimens was established.
CONCLUSIONS: The endothelial presence of SOX2 both in oral potentially malignant and malignant lesions suggests that SOX2 may be implicated in the microvascularization process and associated with the degree of dysplasia in OL. The expression of CD147 may be attributed both to local inflammation and tumorigenesis. The implementation of CD147 in larger groups of tissue samples will shed some light on its role in cancer and inflammation. The evidence so far supports the need for more studies, which may support the clinical significance of these novel cancer stem cell biomarkers.

A fibrosarcoma is a neoplastic growth originating from malignant, fibroblast-like mesenchymal cells. This malignant tumor shows an increased tendency for expansion and recurrence and a propensity to metastasize, especially to the lungs. Despite their rarity, fibrosarcomas have the potential to manifest in any anatomical location. An oncologist referred their patient due to reported mandibular discomfort, ache, and swelling. The biopsy revealed a fibrosarcoma resembling a periapical lesion of endodontic origin. The timely intervention and the collaboration among different but complementary medical and dental specialties ensure that the patient may enjoy a prolonged life expectancy as symptom-free as possible.

Demographic features, suggestive gynaecological symptoms, and immunohistochemical expression of endometrial β-catenin have a prognostic capacity for endometrial hyperplasia and carcinoma. This study assessed the interaction of all variables and developed risk stratification for endometrial hyperplasia and carcinoma.
This cross-sectional study was conducted from January 2023 to July 2023 at two teaching hospitals in Makassar Indonesia. Patients (< 70 years old) with suggestive symptoms of endometrial hyperplasia or carcinoma or being referred with disease code N.85 who underwent curettage and/or surgery for pathology assessment except those receiving radiotherapy, or chemotherapy, presence of another carcinoma, coagulation disorder, and history of anti-inflammatory drug use and unreadable samples. Demographic, and clinical symptoms were collected from medical records. Immunohistochemistry staining using mouse-monoclonal antibodies determined the β-catenin expression (percentage, intensity, and H-score) in endometrial tissues. Ordinal and Binary Logistic regression identified the potential predictors to be included in neural networks and decision tree models of histopathological grading according to the World Health Organization/WHO grading classification.
Abdominal enlargement was associated with worse pathological grading (adjusted odds ratio/aOR 6.7 95% CI 1.8-24.8). Increasing age (aOR 1.1 95% CI 1.03-1.2) and uterus bleeding (aOR 5.3 95% CI 1.3-21.6) were associated with carcinoma but not with %β-catenin and H-Score. However, adjusted by vaginal bleeding and body mass index, lower %β-catenin (aOR 1.03 95% 1.01-1.05) was associated with non-atypical hyperplasia, as well as H-Score (aOR 1.01 95% CI 1.01-1.02). Neural networks and Decision tree risk stratification showed a sensitivity of 80-94.8% and a specificity of 40.6-60% in differentiating non-atypical from atypical and carcinoma. A cutoff of 55% β-catenin area and H-Score of 110, along with other predictors could distinguish non-atypical samples from atypical and carcinoma.
Risk stratification based on demographics, clinical symptoms, and β-catenin possesses a good performance in differentiating non-atypical hyperplasia with later stages.