Immunohistochemical Expression of Ki-67, Dopamine D1 and Dopamine D2 Receptors in Meningiomas in a Tertiary Institution in Mexico

Objectives Meningiomas (MNGs) are the most common intracranial tumors found in the adult population. While most intracranial MNGs may be surgically removed, a subset of patients remains ineligible for conventional treatment. This is either because of a lack of surgical access or due to atypical, anaplastic or invasive characteristics of the tumors. These patients may benefit from targeted therapies that focus on cell receptor expression. The aim of this study was to assess dopamine receptor (DR) and Ki-67 expression in the MGNs of patients treated with surgery in the Instituto Nacional de Neurología y Neurocirugía, Mexico. Materials and methods This study analyzed 23 patients with confirmed MNG diagnoses (10 female and 13 male (mean age: 44.5 years)) who had undergone surgical resection between 2010 and 2014 at our institution. In the collected samples, we performed analyses for Ki-67, Dopamine 1 and Dopamine 2 receptors' expression. Results For the markers Ki-67, DR-D1 and DR-D2, the mean percentual expressions were 18.9%, 23.02% and 8.33%. No significant correlation was found between the expressions of these receptors and the studied MNG characteristics. The expression index of Ki-67 showed a significant relation with mean age (p = 0.03) and prolactin levels (p = 0.02). Conclusions Samples showed varied expressions of the studied receptors. Despite the difference in expressions between the markers, more studies are needed to confirm the findings. In contrast to previous studies, we could not find any relationship between D2-R and tumor characteristics.

Anti-Hu-Associated Encephalomyelitis as a Presentation of Primary Extrapulmonary Small Cell Carcinoma of the Small Bowel: A Case Report

Small cell carcinoma (SCC) is a neuroendocrine tumor (NET) commonly found in the lung, known for rapid proliferation and early metastasis. Extrapulmonary small cell carcinomas (ESCC) are rare, with GI tract carcinomas exceedingly so. Due to the lack of clinical data on the treatment of ESCC, the standard regimen is the same as the SCC of the lung. Documented accounts of paraneoplastic encephalomyelitis associated with NETs are also uncommon. We present a patient who suffered from neurologic deficits before being diagnosed with paraneoplastic encephalomyelitis from a duodenal ESCC. The patient presented with ear pain and hematemesis. New symptoms arose after the resolution of initial symptoms, including shortness of breath and numbness. Autoimmune workup was positive for anti-Hu antibodies. A position emission tomography (PET) scan showed increased uptake in the duodenal region. Biopsy results from a duodenal ulcer revealed poorly differentiated neuroendocrine carcinoma with positive synaptophysin and strong positivity of Ki-67, consistent with ESCC. Numerous treatments, including platinum-based chemotherapy, yielded no neurologic improvement for the patient. This case details an atypical presentation of ESCC, which should be considered in patients suspected of paraneoplastic encephalomyelitis.

Gastrointestinal Stromal Tumor and Ki-67 as a Prognostic Indicator

Gastrointestinal stromal tumors (GISTs) albeit rare, are the most common mesenchymal neoplasms of our gastrointestinal (GI) tract. GISTs present with nonspecific symptoms and are found incidentally on endoscopy or imaging. A significant portion of GIST diagnoses expresses KIT/CD117 and DOG-1 tissue markers which are pathognomonic for GIST. More recently, Ki-67 was found to be a significant prognostic marker for determining the risk of recurrence. We present a patient with a mesenchymal mass in the small intestine with pathognomonic features of GIST and expression of Ki-67, an important immunocytochemical marker of proliferation. The patient was a 71-year-old male with a history of hyperlipidemia and hypertension. He presented to the emergency department complaining of bloody diarrhea for two days, with associated nausea, vomiting, and abdominal cramping. Initial blood pressure on presentation was 77/52 mm Hg. Computed tomography (CT) of the abdomen and pelvis revealed a large solid mass with cystic components. The mass was not visualized with esophagogastroduodenoscopy or colonoscopy, and surgical intervention was warranted. A 14 cm x 11.5 cm x 10 cm tumor was found in the ileum. The tumor was excised with small bowel segmental resection and the specimen was sent for pathological evaluation. Immunohistochemical analysis confirmed the diagnosis of GIST with diffuse CD117/c-Kit protein expression. The tumor was high grade with a high mitotic rate at 30 mitoses/50 high-power fields (HPF) and had spindle cell morphology. Of note, 10% of the tumor cells were positive for Ki-67. GISTs have a high risk of recurrence and a more favorable prognosis with advancements in management. Prior to imatinib therapy in the early 2000s, GISTs prognosis was very poor, as they are resistant to most conventional chemotherapeutic agents and radiation. While the prognosis is fair, surgical resection and imatinib therapy have improved outcomes and risk of recurrence. Prognosis and risk of recurrence can be determined by assessing the mitotic rate, tumor size, and recently, expression of Ki-67. Ki-67 provides a reliable and reproducible approach to assess the prognosis of GIST.

The association between Ki-67 expression and the clinical pathological characteristics of colorectal cancer: A protocol for a systematic review and meta-analysis

BACKGROUND

This study will explore the association between Ki-67 expression and clinical pathological characteristics (CPC) of colorectal cancer (CC).

METHODS

We will search relevant studies from electronic databases (Cochrane Library, PUBMED, EMBASE, Scopus, Cumulative Index to Nursing and Allied Health Literature, China Biology Medicine, and China National Knowledge Infrastructure) from beginning to April 1, 2020 without language and publication time limitations. We will consider all case-controlled studies (CCSs) or randomized controlled studies (RCSs) investigating the association between Ki-67 expression and CPC of CC. We will appraise study quality of CCSs by Newcastle-Ottawa Scale, and RCSs by Cochrane risk of bias tool. Statistical analysis will be carried out by Review Manager 5.3 software.

RESULTS

The present study will explore the association between Ki-67 expression and CPC of CC.

CONCLUSION

Its findings may summarize scientific evidence of the association between Ki-67 expression and CPC of CC, and may provide helpful evidence for clinical practice.Systematic review registration: PROSPERO CRD42020173795.

Immunohistochemical Expression of ki-67 and p53 in Colorectal Adenomas: A Clinicopathological Study

OBJECTIVES

To evaluate the significance of P53 and Ki-67 expression as immunohistochemical markers in early detection of premalignant changes in different types of colorectal adenomas. Also, to correlate immunohistochemical expression of the two markers with different clinicopathological parameters including; age, and sex of the patient, type, site, size and grade of dysplasia of colorectal adenomas.

METHODS

Forty-seven polypectomy specimens of colorectal adenomas were retrieved from the archival materials of the Gastrointestinal and Hepatic Diseases Teaching Hospital in Baghdad from 2009 - 2010. Four µm section specimens were stained by immunohistochemical technique with Ki-67 and P53 tumor markers. P-values <0.05 were considered statistically significant.

RESULTS

Immunohistochemical expressions of Ki-67 and P53 had a significant correlation with the size and grade of dysplasia in colorectal adenomas. However, there was no significant correlation among the immunohistochemical expression of Ki-67 and P53 with the age and gender of the patient, and the type and site of colorectal adenomas. There was no significant correlation between Ki-67 and P53 expressions in colorectal adenomas. Villous adenomas of colorectum showed a significant correlation with the grade of dysplasia, while there was no significant correlation between size and site of colorectal adenoma with the grade of dysplasia.

CONCLUSION

High grade dysplasia with significant positive immunohistochemical markers of Ki-67 and P53 could be valuable parameters for selecting from the total colorectal adenoma population, those most deserving of close surveillance in follow-up cancer prevention programs. It is closely linked with increasing age particularly in patients with a large size adenoma of villous component in their histology.

Gallbladder carcinoma: the role of p53 protein overexpression and Ki-67 antigen expression as prognostic markers

BACKGROUND

The overexpression of p53 protein and the expression of Ki-67 antigen may affect the survival of patients with gallbladder carcinoma. This association has been tested in a series of 41 patients with relatively early carcinoma of the gallbladder.

METHODS

Forty-one surgical specimens from patients with a postoperative histological diagnosis of gallbladder carcinoma were studied. All patients were operated by simple cholecystectomy only because the tumours were not advanced and/or their general condition was poor. Patients submitted to radical operations were excluded. p53 expression was calculated from nuclear staining according to the intensity and extent of positive cells, as graded on a scale from 1 to 3; a combined score of >3 was considered as overexpression. Ki-67 expression was calculated by the MIB-I index: the percentage of positively stained tumour cell nuclei out of the total tumour cells counted (n = 1000); >20% of stained cells was considered positive.

RESULTS

Twenty-nine gallbladder carcinomas (71%) overexpressed p53 protein in the cell nuclei. No significant differences were found in relation to cell differentiation on the level of tumour infiltration through the gallbladder wall. Five-year survival of patients with gallbladder carcinoma overexpressing p53 was 17.2%, while survival of patients without p53 overexpression was 30% (not significant). Twenty-four cases (58.5%) were considered positive for the MIB-I index. There were no differences between the grade of cell differentiation and wall infiltration. Five-year survival of the patients with a MIB-I positive index was 9.2% as opposed to 27.7% for those with a negative index (not significant).

CONCLUSIONS

p53 protein nuclear overexpression and Ki-67 protein expression in gallbladder carcinoma were not related to histological differentiation, level of gallbladder wall invasion or patient survival.