Glioma dataset from Rabat: Clinicopathological, immunohistochemical and disease progression features of 32 Moroccan patients with diffuse Glioma

The Moroccan Glioma Dataset contains the clinical data of 32 patients with glioma. The clinical data including demographic data (age, sex), tumor characteristics (tumor location, Glioma type, Karnofsky performance score, mitotic activity, cell density, necrosis, endotheliocapillary vascular proliferation, MRI contrast pick-up, corpus collosum infiltration and Oedema), treatment strategy (subtotal resection, gross resection, biopsy, radiotherapy, chemotherapy), expression pattern of tumor biomarkers (IDH1, HIF-1alpha, P53, Ki-67), and survival data (Kaplan-Meier curves for disease progression). The dataset can be used to relate tumor characteristics to tumor biomarkers and to predict disease progression for a better treatment management. The data were presented, analyzed, and described in the article “Immunohistochemical expression of HIF-1α, IDH1 and TP53: prognostic profile of Moroccan patients with diffuse glioma” published in Journal of Chemical Neuroanatomy [1].


Keywords:
Glioma Hypoxia Immunohistochemistry HIF-1alpha IDH1 TP53 Disease progression of tumor biomarkers (IDH1, HIF-1alpha, P53, Ki-67), and survival data (Kaplan-Meier curves for disease progression). The dataset can be used to relate tumor characteristics to tumor biomarkers and to predict disease progression for a better treatment management. The data were presented, analyzed, and described in the article "Immunohistochemical expression of HIF-1 α, IDH1 and TP53: prognostic profile of Moroccan patients with diffuse glioma" published in Journal of Chemical Neuroanatomy [1] .
© 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

Value of the Data
• This dataset provides clinical, radiological, histological, and immunohistochemical data, and outlined tumors from 32 patients with glioma. Currently, no data that provides all this information for a single Moroccan patient cohort is available. • This data can be used to stratify patients according to their immunohistochemical profile, and to personalize treatment according to hypoxia marker expression, and to predict disease progression. • These data may be used, or reused, in research that involves clinical features of diffuse glioma for comparative reasons, or to incorporate them as part of a larger dataset.

Data Description
The dataset consists of one Excel file, one word file (Patient follow up template) and Immunochemistry images. The Excel file contains the raw data and includes: patient ID, demographic data (age, sex), tumor characteristics (tumor location, glioma type, Karnofsky performance score, mitotic activity, cell density, necrosis, endotheliocapillary vascular proliferation, MRI contrast pick-up, corpus collosum infiltration and Oedema), treatment strategy (subtotal resection, gross resection, biopsy, radiotherapy, chemotherapy), expression pattern of tumor biomarkers (IDH1, HIF-1alpha, P53, Ki-67), and disease progression.

Patients
A total of 71 consecutive patients with a potential diffuse glioma diagnosis on neuroimaging were considered for recruitment between June 2017 and December 2018. After pathologic examination, a total of 32 patients (22 with glioblastoma, and 10 with glioma grade II and III) were included in this study. All the cases underwent either surgical gross or subtotal resection or biopsy. The anatomopathological examination was carried out at the Pathological Anatomy Laboratory of the Specialities Hospital in Rabat, by experienced neuropathologists. Adjuvant chemotherapy and radiotherapy were fully discussed with patients before the start of treatment, and all patients had received adequate chemotherapy and radiotherapy according to the Stupp standard protocol for gliomas [2] .

Inclusion criteria
• Male and female patients with histologically confirmed diffuse glioma WHO 2016.
• Patients of Moroccan nationality.
• Patients from the Hospital of Specialties, and the National Institute of Oncology in Rabat. • Adult patients over the age of 18.

Exclusion Criteria
• Patients with other brain tumors or brain metastasis.
• Patients over the age of 80.
• Patients of other nationalities.
• Patients with grade I glioma WHO 2016.

Histological Evaluation
The histological type and grade of the tumour were examined by a neuropathologist and determined according to the 2016 WHO Classification of Central Nervous System tumours [3] . The tumours tissue sections are stained with H&E (Hemalun Eosin) stains.

Immunohistochemistry for Paraffin Sections
After a dehydration step by immersion in alcohol baths of increasing concentrations (70, 80, 90 and then 100%), all tumor samples from biopsies or surgical specimens were fixed in 10% neutral buffered formalin for 2 to 24 h in room temperature, and after standard anatomopathological examination are embedded in paraffin.

The other steps of the IHC is as follows
-Paraffin sections (4-μm-thick) were cut by microtome and floated in water bath.
-The floating paraffin sections were mounted on chromo-gelatinized glass slides using a brush. -Drying in the oven at 56 °C during 1 h -Dewaxing in 2 baths of Toluene for 10 min each.
-Hydration with decreased concentration of alcohol (100%, 90%, 80%, and then 70%) for 5 min each, and tap water for 5 min. -Antigen retrieval by immersion of the slides in sodium citrate buffer solution (at corresponding antibody pH) and heating in a microwave at 1200W for 5 min. -The buffer and slides must cool down to room temperature before three times washing step in PBS (at corresponding antibody pH) for 5 min each. -Demarcation of the sections by the PAP pen in order to delimit the field of the reactions -Blocking of endogenous peroxidase activity by 3% hydrogen peroxide for 5 min followed by brief rinse in PBS.

Immunostaining Quantification
The expression of HIF-1 α is assessed by counting the percentage of positive cells over the total cells in each slide. The staining of HIF-1 α is evaluated as follows: staining is considered negative/weak staining when ≤10% of cells are positives and positive/strong staining of HIF-1 α when > 10% of cells are positives.
The Ki-67 index was estimated as the percentage of stained cell nuclei among at least 20 0 0 tumor cells in the areas richest in positive cells (number of positive nuclei per 20 0 0 cells). Tumors that express Ki-67 at levels of 2% or above were regarded as positive.
IDH1 immunoreactivity was considered "positive" when a large proportion of tumor cells showed high cytoplasmic reactivity, whereas it was considered "negative" if little or no cytoplasmic reactivity was observed.
The evaluation of p53 expression was performed semi-quantitatively by continuously counting more than 10 0 0 tumor cells in the areas of highest expression. According to the percentage of tumor cells with reactivity, we considered p53 positive if the percentage of cells with positive reactivity over 10%, or low or negative reactivity if the percentage of cells is < 10%.

Evaluation of Mitotic Activity
The estimation of the mitotic activity index was done on glass slides using Leica light microscopy where mitosis is counted in 10 high power fields (40 × magnification). For a mitotic index of 6 mitoses or more per 10 high power fields, mitotic activity was considered present. The differentiation of true mitoses from apoptotic bodies, dark nuclei and tissue artefacts, requires careful work.

Disease Progression
The percentage of patients with disease progression was calculated from the time of surgery to one year, using one of the following criteria: an increase in tumor size of more than 20% in MRI and CT scan, the tumor has spread to healthy tissue, or the patient's condition worsens through paralysis or blindness. All patients were followed up every 3 months.

Declaration of Competing Interest
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.