Prevalence of Mismatch Repair Deficiency in Advanced Solid Tumors (Colorectal Cancer and Non-Colorectal Cancer) in One Mexican Institution.

: Mismatch repair (MMR) status is an important prognostic and predictive indicator in cancer, distinguishing proficient (pMMR) tumors from deficient (dMMR) ones. This study aimed to determine the prevalence of dMMR in colorectal (CRC) and selected non-CRC solid tumors (gastric, esophageal, and endometrial cancers). : This retrospective study was conducted at a private health institution in Mexico City, analyzing patients diagnosed with colorectal, gastric, esophageal, or endometrial cancer from January 2017 to December 2020.

Replacement of the main bile duct by bioprosthesis in an experimental porcine model (24-month results).

Background: Cholecystectomy for conditions like iatrogenic injury during cholecystectomy can lead to complications such as bile duct injuries, necessitating alternative options like bioprosthesis.

Methods: This study evaluated a bioprosthesis's efficacy in maintaining bile duct continuity over 24 months in 16 male pigs.

Results: The bioprosthesis was implanted in the common bile duct of three-month-old animals, with follow-ups at 1, 6, 12, 18, and 24 months.

Navigating HER2-Low Testing in Invasive Breast Cancer: Update Recommendations for Pathologists.

The article discusses the importance of accurately distinguishing HER2-low from HER2-negative breast cancer, as novel ADCs have demonstrated activity in a large population of patients with HER2-low-expressing BC. While current guidelines recommend a dichotomous classification of HER2 as either positive or negative, the emergence of the HER2-low concept calls for standardization of HER2 testing in breast cancer, using currently available assays to better discriminate HER2 levels. This review covers the evolution and latest updates of the ASCO/CAP guidelines relevant to this important biomarker in breast cancer, including still-evolving concepts such as HER2 low, HER2 heterogeneity, and HER2 evolution.

Molecular Mechanisms Involved in MAFLD in Cholecystectomized Patients: A Cohort Study.

Gallstone disease and metabolic dysfunction-associated fatty liver disease (MAFLD) share numerous common risk factors and progression determinants in that they both manifest as organ-specific consequences of metabolic dysfunction. Nevertheless, the precise molecular mechanisms underlying fibrosis development in cholecystectomized MAFLD patients remain inadequately defined. This study aimed to investigate the involvement of farnesoid X receptor 1 (FXR1) and fibroblast growth factor receptor 4 (FGFR4) in the progression of fibrosis in cholecystectomized MAFLD patients.

Mandibular Metastasis as the First Manifestation of Hepatocellular Carcinoma: A Case Report.

Metastatic malignancies of the oral cavity are rare lesions, accounting for only 1-4% of all oral malignancies, and can occur in the jaw bones, the oral soft tissues, or even both. Although hepatocellular carcinoma is the most common primary hepatic tumor, no more than 1% of the cases show oral involvement. When metastatic tumor involves the oral cavity, the most frequent site is the posterior angle of the mandible.

Expression of Programmed Death Ligand 1 in Breast Cancer in Mexican Women.

Background: Breast cancer is one of the most common malignant forms of neoplasia worldwide; programmed death protein 1 (PD-1), an inhibitory receptor of T lymphocytes, and its ligand programmed death ligand 1 (PD-L1), play an important role in the ability of tumor cells to evade the host's immune system.

Methods: We conducted a descriptive, observational study using retrospective data and an open evaluation using immunohistochemistry to determine the general prevalence of PD-L1 expression in 63 women with breast cancer who underwent a modified radical mastectomy, or quadrantectomy, with axillary lymph node removal.

Results: The prevalence of PD-L1 expression was 32% in patients with breast cancer treated with radical mastectomy.

Identification of Hepatic Dendritic Cells in Liver Biopsies Showing Steatosis in Patients with Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD) Associated with Obesity.

BACKGROUND Metabolic dysfunction-associated fatty liver disease (MAFLD) is now the term used for hepatic steatosis in patients who are overweight or obese, have type 2 diabetes mellitus (T2DM), or evidence of metabolic dysregulation. The prevalence of MAFLD among morbidly obese subjects is 65-93%. Hepatic dendritic cells (hDCs) are antigen-presenting cells that induce T cell-mediated immunity.

Impact of the Discordance Between Scales of Memorial Sloan-Kettering Cancer Center and International Metastatic Renal Cell Carcinoma Database Consortium in Patients' Prognosis With Metastatic Renal Cancer.

Background: In Mexico, about 30% of renal cancer patients are diagnosed in a metastatic state. Despite the recent advances in the treatment of cancer, metastatic renal cancer is still an incurable illness. Thus, identifying prognostic factors helps improve prognosis accuracy and survival prediction for patients.

Neuroendocrine Tumor of the Common Bile Duct: Case Report.

Carcinoma of the extrahepatic biliary tract accounts for <2% of all cancers. Neuroendocrine tumor of the extrahepatic bile duct is very rare, and there are <200 cases reported since 1959. The preoperative diagnosis is infrequent (5.

Epithelial-Cadherin Expression Is Associated With Better Recurrence-Free and Overall Survival in Invasive Lobular Breast Cancer in Mexican Women.

Background: There are different clinicopathological characteristics that are associated with the prognosis in patients with breast cancer. To date, the prognostic valor of for epithelial cadherin (E cadherin) expression in invasive lobular breast cancer remains unknown.

Methods: A retrospective single-center study that included 207 patients with primary invasive lobular breast cancer was conducted.

[An unusual association of malakoplakia and adenocarcinoma of the prostate].

Malakoplakia is a chronic inflammatory process caused by a lysosomal defect in bacterial digestion. Although rare, it occurs more frequently in the genitourinary tract and in patients with immune dysfunction. The bladder is the most commonly affected site, although cases have been reported in other organs, including the prostate gland.

Impact of Testicular Germ Cell Tumor Laterality on Recurrence-Free Survival in the Mexican Population.

Background: To date, the prognostic value of laterality for testicular germ cell tumors remains unknown. Herein, we describe this prognostic factor in the Mexican population.

Methods: A retrospective single-center study that included 37 patients with primary testicular germ cell tumors was conducted.

Prevalence and Molecular Profile of Breast Carcinoma Using Immunohistochemistry Markers in Mexican Women.

Background: In Mexico, breast cancer is the leading cause of death by malignant tumors in women aged 20 and older. The World Health Organization estimates that 69% of deaths caused by breast cancer occur in developing countries. Little is known about the prevalence of breast carcinoma in Mexico and its molecular subclassification.

Myoepithelial Carcinoma Arising in a Plasmacytoid Myoepithelioma of the Parotid Gland Synchronized with Melanoma: A Case Report and Review of the Literature.

Myoepithelial carcinoma, also known as malignant myoepithelioma, is considered an extremely rare (0.45-1%) malignant salivary gland neoplasm. Approximately 100 cases have been reported in the English-language literature on myoepithelial carcinoma.

Impact of the Type of Analgesic Therapy on Postsurgical Complications of Patients with Kidney Cancer Undergoing Nephrectomy.

Background: The treatment of kidney cancer usually involves surgery, and in some cases systemic therapy. Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to control postsurgical pain in patients undergoing nephrectomy for renal cancer. Nevertheless, the association between these drugs and adverse postsurgical outcomes, including deterioration of renal function, is not fully established.

Epidemiological Profile of Patients of Aged 65 Years and Over in a University Private Hospital.

Objectives: An increase in life expectancy is predicted for the general population and, by 2050, about one billion people will be older than 65 years. The Global Cancer Incidence, Mortality and Prevalence database estimates that 1.2 million people of this age will have cancer; this number represents 58% of new cases in the American population.

Risk of Pneumonitis with the Use of Different Immune Checkpoint Inhibitors in a Mexican Population.

Purpose: The incidence of pneumonitis reported in previous trials in patients with advanced cancer and use of programmed cell death protein 1 (PD-1) immunotherapy inhibitors was 2.7-3.6%.

Spontaneous regression as a 'burned-out' non-seminomatous testicular germ cell tumor: a case report and literature review.

Testicular germ cell tumors (TGCTs) are the most frequent type of cancer in young adults. An exceptional event is the spontaneous regression (SR) of the primary tumor. Herein, we describe a burned-out non-seminomatous TGCT case and relevant literature review.

Searching for the Culprit: Metastases from a Cancer of Unknown Primary.

We report a case of metastases from a cancer of unknown primary whose primary site could not be identified during the appropriate pretreatment evaluation. The patient was a 58-year-old woman with a history of passive smoking and with no history of cancer in the family. Her current condition started with asthenia, adynamia, and pallor, followed by palpitations.

Reproducibility of the EGFR immunohistochemistry scores for tumor samples from patients with advanced non-small cell lung cancer.

Epidermal growth factor receptor (EGFR) is overexpressed in >60% of non-small cell lung cancer (NSCLC) cases. In combination with radiotherapy or chemotherapy, first-line treatments with antibodies against EGFR, including cetuximab and necitumumab, have demonstrated benefits by increasing overall survival (OS), particularly in patients who overexpress EGFR. The present study evaluated the interobserver agreement among three senior pathologists, who were blinded to the clinical outcomes and assessed tumor samples from 85 patients with NSCLC using the H-score method.

Histopathological transformation to small-cell lung carcinoma in non-small cell lung carcinoma tumors.

Lung cancer is the principal cause of cancer-related death worldwide. The use of targeted therapies, especially tyrosine kinase inhibitors (TKIs), in specific groups of patients has dramatically improved the prognosis of this disease, although inevitably some patients will develop resistance to these drugs during active treatment. The most common cancer-associated acquired mutation is the epidermal growth factor receptor (EGFR) Thr790Met (T790M) mutation.

Cystadenomas of the liver and extrahepatic bile ducts: Morphologic and immunohistochemical characterization of the biliary and intestinal variants.

Cystadenomas of the liver and extrahepatic bile ducts (EHBD) are uncommon but distinctive neoplasms whose terminology and epithelial phenotype have been a source of controversy. We reviewed 20 cases, 16 arising in the liver and 4 in the EHBD. Eighteen patients were women, with a mean age of 36.

Neutrophil gelatinase-associated lipocalin (NGAL) and matrix metalloproteinase-9 (MMP-9) prognostic value in lung adenocarcinoma.

Prognosis in patients with lung cancer is poor. Neutrophil gelatinase-associated lipocalin (NGAL) and matrix metalloproteinase-9 (MMP-9) are proteins involved in the invasion and metastases of cancer. The objective of this study is to determine if there is a relationship between tumor expression of NGAL and MMP-9 in lung adenocarcinoma patients with prognosis and overall survival.

Bone metastases as the initial presentation of hepatocellular carcinoma. Two case reports and a literature review.

Hepatocellular carcinoma (HCC) is the most common primary tumor of the liver and is the fifth most common cancer in the world; its incidence has been increasing in recent years. Extrahepatic spread is present at the time of diagnosis in only about 5 to 15% of patients. Skeletal metastasis of HCC occurs less frequently compared with other cancers and is considered a rare primary form of presentation.