Chromosome-1 abnormalities in Childhood B-Lymphoblastic Leukemia - An analysis with reference to clinical variables and survival outcome.

Background: Chromosome-1 abnormalities (C1As) are common genetic aberrations in hematological malignancies. We sought to evaluate significance of these abnormalities with reference to clinical characteristics and survival outcome in a pediatric B-Lymphoblastic Leukemia (B-ALL) cohort. Methods: This is a retrospective study conducted in cytogenetic section of Indus Hospital and Health Network. Data was retrieved from October 2020 to July 2022 for childhood B-ALL cases exhibiting C1As. Chromosome analysis was performed on Cytovision MB8 using G-banded metaphases derived from unstimulated bone marrow culture. Results were recorded according to the International System for Human Cytogenetic Nomenclature (ISCN-2020). Data analyzed using SPSS, version 24.0. Results: C1As were observed in 60/450 (13.3%) cases of B-ALL. Among C1As, 29 (48%) cases had t(1;19). There were 13 (45%) balanced and 16 (55%) unbalanced translocations. The aberrations without t(1;19) were seen in 31 (52%) cases including 1q duplication with hyperdiploidy in 14 (45%) cases. The median age for C1As with and without t(1;19) was eight years and six years while the median leukocyte count was 32 x 109/L vs. 17 x 109/L. Event-free survival (EFS) for cases with and without t(1;19) was 69% and 74.2% respectively. Conclusion: Despite the fact that the t(1;19) positive group had a higher median age, a higher white cell count and more CNS positives, the difference in EFS is statistically insignificant when compared to the t(1;19) negative cases. Furthermore, we found a survival difference between balanced and unbalanced t(1;19) groups, which is statistically insignificant but warrants large-scale prospective studies for further understanding.

Plasmablastic Lymphoma in a Human Immunodeficiency Virus-positive Child With a Suspicion of Concomitant Primary Immunodeficiency Disorder.

Plasmablastic lymphoma (PBL) occurs in the setting of immunodeficiency, in association with human immunodeficiency virus (HIV) infection, in elderly patients, and in the posttransplantation state. It is exceptionally rare in children. PBL is an aggressive lymphoma with a poor prognosis. We present a case of pediatric PBL in an HIV-positive child with suspicion of a concomitant underlying immune deficiency state other than HIV. A 7-year-old girl presented to the pediatric emergency department with complaints of fever and painful swelling on the left side of her face for 15 days, associated with headache, snoring, and difficulty in breathing. She had a history of watery diarrhea, oral thrush, recurrent fever, and hospitalizations for skin infections since the age of 1 year. Histopathological findings were consistent with PBL. Her HIV RNA polymerase chain reaction was positive. She was offered chemotherapy based on the FAB/LMB 96 protocol. This case demonstrates an aggressive presentation of a rare entity, HIV-associated PBL, in a child, with underlying immunodeficiency and highlights the issues which caused a significant challenge in making the diagnosis. The presence of HIV infection and contradicting other immunologic investigations posed a dilemma in establishing an association of PBL in this child. The outcome of patients with this tumor is associated with high mortality.

Cytogenetic Profiling In Paediatric Acute Leukaemia; A Report On 746 Newly Diagnosed Paediatric Cases Analyzing The Spectrum Of Recurring Chromosomal Rearrangements In B Cell Lymphoblastic And Acute Myeloid Leukaemia.

Background: Cytogenetics is evolving and different molecular mechanisms we know now have proved to be of diagnostic and prognostic significance in both acute lymphoid (ALL) and myeloid leukaemia (AML). This study aims to find out and compare the occurrence of different cytogenetics in paediatric acute leukaemia. Methods: This is a cross-sectional study of diagnosed B-ALL and AML patients presenting at The Indus Hospital. We studied FISH and karyotype in BALL and FISH in AML patients. FISH analysis shows a total of 69 (12.8%) of B ALL patients had cytogenetic abnormalities. BCR-ABL1 was positive in 5.1%, ETV6/RUNX1T1 in 8.6% and KMT2A in 2.3% individuals. Karyotype reveals hyper diploidy in 24.3%, Monosomy in 1.94%, and t (1:19) and t (17:19) were observed in 5.8% and 0.24% cases respectively. FISH analysis in AML cases reveal positivity of t (8:21) in 26.4%, INV (16) in 6.1% while PML-RARA t(15:17) was done on morphological suspicion in 17 cases; all of which showed positivity; making 7.9% of the total AMLs. The study demonstrated a wide spectrum of heterogeneity in paediatric acute leukaemia. Conclusion: Hyperdiploidy was the most common cytogenetic abnormality. We report a lower incidence of t (12:21), compared to the world. We showed a higher prevalence of RUNX1/RUNX1T1 in young children. The prevalence of core binding factor AML was 32.5%.

Extramedullary hematopoiesis in an inguinal lymph node: an unusual presentation of primary myelofibrosis.

BACKGROUND: Extramedullary hematopoiesis (EMH) is a proliferation of hematopoietic tissue outside of the bone marrow medullary space. It is a pathophysiologic response, more often associated with either a benign reactive hematological disease or a myeloproliferative neoplasm (MPN). Identification of EMH in adults is always pathologic. It is highly unlikely for a myeloproliferative neoplasm to present with inguinal lymphadenopathy. An unusual and complex case can be precisely diagnosed via a multidisciplinary approach involving experts from various modalities of laboratory. In this regard, the present case highlights the importance of an integrated approach in establishing the diagnosis. CASE PRESENTATION: We report a case of a 61-year-old male patient of primary myelofibrosis who presented with extramedullary hematopoiesis in an inguinal lymph node. The patient initially presented with generalized symptoms including anemia, fatigue, abdominal pain, and weight loss. On examination, massive splenomegaly. Chest X-ray revealed consolidation which was secondary to right-sided pleural effusion. Therefore, he was suspected to have a lung carcinoma. However, lymph node biopsy revealed extensive fibrosis, consequently effacing the nodal architecture. An abnormal blood picture raised the possibility of bone marrow infiltration. Extensive panel of markers is tested on lymph node and bone trephine. Cytogenetic studies with G-banding analysis and fluorescence in situ hybridization (FISH) played a significant role in deriving clinical decision. Translocations identified in conventional cytogenetic workup led to the diagnosis of primary myelofibrosis. The case is being reported due to unusual presentation of PMF. CONCLUSION: In conclusion, it is a distinctive case of myeloproliferative disorder initially presented with extramedullary hematopoiesis and through multidisciplinary workup successfully diagnosed as primary myelofibrosis. Awareness of unique clinical presentations and integrated approach towards diagnosis is the key to such challenging cases.

Frequency, Distribution Of Subtypes And Immunohistochemical Profile Of Non-Hodgkin Lymphoma In Paediatric And Adolescent Patients.

BACKGROUND: Non-Hodgkin lymphoma is a common malignant disorder in paediatric and adolescent age group. There is a need of large-scale studies to understand the disease pattern in Pakistan as no official registry exist in most of the developing countries. This study comprised a large cohort of 223 patients, spanned over a decade from January 2008-December 2019 and aimed to report the prevalence of subtypes, demographics and immunohistochemical profile from this region. METHODS: Retrospective study, conducted at Indus hospital and health network and Ziauddin university hospital, Karachi, Pakistan. Sequential data analysis was carried out on all consecutive samples including both needle and excisional biopsies of patients below 18 years of age. Morphological examination of H&E stained sections along with immunohistochemistry is performed in order to identify subtypes and immunophenotypic patterns using an extensive panel of markers. RESULTS: Our results demonstrate 66% B-cell lymphomas while 34% T-cell lymphomas. Overall male to female ratio was 3.3:1 with median age 8 years (1.1-17 years). Among B-cell lymphoma, Burkitt lymphoma is most common while in T-cell, T-lymphoblastic lymphoma is the most common subtype. In anaplastic large cell lymphoma category, null cell phenotype was predominant, i.e., 65%. T-NHL frequency is found to be higher in our population. However, results of immunohistochemistry are similar to published literature. CONCLUSIONS: The study will help to identify disease patterns in terms of subtypes of NHL and its immunohistochemical profile that plays a vital role in diagnostic, prognostic and therapeutic implications.

Histopathological Features Of Denosumab Treated Giant Cell Tumours Of Bone "A Single Institutional Experience" At A Tertiary Care Center, Karachi.

BACKGROUND: Giant cell tumour (GCT) is a primary benign, locally aggressive bone tumour. Treatment is surgical however, denosumab has been increasingly used as a treatment in recurrent or unresectable locally advanced GCT because of its effect in reducing tumour size. Denosumab treated GCT can exhibit a wide array of histopathological features resulting in diagnostic problems for pathologists. Our study aimed at identifying these histopathological features to aid pathologists in reaching a correct diagnosis. METHODS: Our study included 20 patients of biopsy-proven GCT cases treated with denosumab. We received specimens for histopathological examination in our institution from January 2018 to March 2020. The demographic and clinical data of these patients were retrieved from the Health Management Information System (HMIS). The slides were retrieved and studied for histopathological changes. RESULTS: The mean age of patients in our study was 29.5 years. There were 11 males and 9 females. Distal radius was most commonly involved bone. On histopathological examination, ovoid to spindle mononuclear stromal cells were seen. Total absence of osteoclast like giant cells was seen in 10 (50%) cases, whereas 3 (15%) cases showed a marked reduction in osteoclast like giant cells. CONCLUSIONS: Denosumab treated GCT of bone can exhibit a wide spectrum of histopathological features. Pathologists need to be mindful of these features. Correlation of histopathological findings with clinical history and radiological features is important to prevent erroneous diagnosis. Treatment history of patients with denosumab is essential as incorrect diagnosis can be made if the history of denosumab treatment is not provided.

High risk histopathological factors in retinoblastoma in upfront enucleated eyes: An experience from a tertiary care centre of Pakistan.

Background & Objectives: The assessment of histopathological risk factors (HRFs) in retinoblastoma in upfront enucleated eyes is important in deciding treatment protocols. Limited data is available from the developing countries as very few studies were conducted on retinoblastoma. The study aims to report this data from Pakistan. Methods: This cross-sectional study included treatment naïve retinoblastoma patients who underwent upfront enucleation between 2017 to 2021. Various tumor characteristics i.e. laterality, size, histologic grade, anaplasia grade, growth pattern, extent and length of optic nerve invasion, pathologic staging, tumor involvement of ocular structures were assessed. High-risk factors such as involvement of anterior chamber, choroidal, scleral, extrascleral, and optic nerve were also noted. Results: A total number of 54 patients were enrolled, out of which 53.7% were females while remaining were males. Median age at presentation was 24 months. Unilateral tumor was seen in 92.6% cases. Most frequent histologic grade was G2 (64.7%) and moderate anaplasia was observed in 59.2% cases. Vitreous involvement was seen in (86.5%). Pathologic staging of most of the tumors was pT1 (39.2%). Assessment of high-risk factors revealed that optic nerve involvement (35.1%) was the most common finding with retrolaminar tumor invasion seen in 75% cases. Choroidal invasion (≤3mm) was seen in 55.6% of patients. Limited involvement of anterior chamber (3.8%), sclera (7.4%), and extrascleral (3.8%) tissue was also observed. Conclusion: The presence of high risk histopathological factors in enucleated eyes diagnosed with retinoblastoma are known to have a profound impact on the risk stratification as well as decision of future treatment plan.

Chemotherapy induced histopathological changes in retinoblastoma, assessment of high risk predictive factors & its correlation with comorbid conditions.

Background & Objectives: Retinoblastoma is a malignant intraocular tumor and its treatment requires a multidisciplinary approach. Chemotherapy is an important modality in treatment of retinoblastoma. The purpose of this study was to assess the histopathological changes in retinoblastomas treated with chemotherapy along with correlation of comorbid conditions with high risk histopathological factors (HRF). Methods: All post-chemotherapy enucleated eye specimens received in the pathology department between 2017 to 2021 were included in the study. Slides were retrieved and reviewed for chemotherapeutic effects, tumor regression, and for assessment of HRF. Patient demographic data, information regarding chemotherapy and co-morbid conditions were retrieved through the hospital database. Chi-square was used to analyze the relation between comorbid conditions and HRF. Results: Chemotherapeutic effects were seen in all eyes with varying degrees of responses. Necrosis, calcification, and gliosis were the most common findings. The majority of eyes showed tumor occupying less than 50% of the eye whereas complete regression was noted in one eye only. Retinal detachment, glaucoma, and buphthalmos were the most common comorbid conditions at the time of diagnosis. Patients with glaucoma were more likely to have ciliary body invasion. Kaplan Meier analysis showed that patients with more than two HRF had decreased survival rates in comparison to those with one or no HRF. Conclusion: Histopathological evaluation of chemotherapy-treated eyes shows varying degrees of response to chemotherapy. Post enucleation histopathological evaluation of the globe plays an important role in assessing disease activity and guiding further treatment to prevent metastasis.

Correlation of clinical and radiological predictors of retinoblastoma with high-risk histopathological features.

INTRODUCTION: Retinoblastoma (RB) tumors having high-risk histopathologic features (HRFs) have an increased risk of metastasis and disease relapse. However, RB has not been studied widely in Pakistan. Therefore, we evaluated the association of clinical, histopathologic, and radiological findings with HRFs in patients with RB who were treated at the Indus Health & Hospital Network in Karachi, Pakistan. METHODS: We enrolled treatment-naïve patients with RB who received upfront enucleation from September 2017 to February 2021. We evaluated enucleated eyes with the Intraocular Classification of Retinoblastoma system and classified HRFs as invasion of the anterior chamber, including the iris and ciliary body, or massive invasion of the choroid, sclera, or optic nerve (postlaminar and/or up to the transection line). RESULTS: Of 117 patients with RB treated at our institution during the study period, 54 received upfront enucleation. Unilateral disease was present in 92.6% of cases. The most frequent disease signs and symptoms included the presence of vitreous seeds (30.6%) and leukocoria (100%), respectively. The most frequent HRFs and radiological findings comprised massive choroidal invasion (15.1%) and anterior chamber enhancement (66.7%), respectively. The majority (62.9%) of patients did not exhibit any HRFs. Female sex, pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma had significant predictive ability for HRF occurrence. CONCLUSION: Pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma are important clinical factors that should be taken into consideration before the management of RB. Early recognition of high-risk histopathological and radiological features is essential for appropriate treatment of RB.

Myoepithelial Carcinoma arising in a background of pleomorphic adenoma.

Carcinoma ex pleomorphic adenoma is a neoplasm of the salivary gland that causes 3.6% of salivary gland tumours and 12% of salivary gland malignancies. It is a myoepithelial or epithelial neoplasm that arises from pleomorphic adenoma, whether primary or recurrent. Historically carcinoma ex pleomorphic adenoma is considered a high-grade malignancy. Salivary duct carcinoma and high-grade adenocarcinoma are the histologic types that most commonly arise in the background of Pleomorphic adenoma. However, 15% of tumours arising in Pleomorphic adenoma are considered low grade and have sluggish growth. Low-grade carcinoma ex pleomorphic adenoma can be difficult to differentiate from cellular pleomorphic adenoma. The case of a 56-year-old female patient who had neck swelling is being presented. The biopsy showed spindle cell component with mild atypia, invasion into surrounding tissue, and increased mitotic activity on the basis of which a diagnosis of Low-grade carcinoma ex pleomorphic adenoma developing in a background of pleomorphic adenoma was made. The morphological and immunohistochemical features confirmed the carcinoma component to be myoepithelial.

Distribution of subtypes and immunophenotypic characterization of 1379 cases of paediatric acute leukaemia.

OBJECTIVES: Acute leukaemia is the most common and highly curable childhood malignancy; subtyping and identification of antigens via immunophenotyping helps in treatment plan as well as minimal residual disease monitoring. METHODS: This retrospective study was conducted at the Haematology section of the clinical laboratories of Ziauddin University Hospital and The Indus Hospital, Karachi conducted at January 1st, 2012 to December 31st, 2017. The study included 1379 cases of de novo acute leukemia from 2012 to 2017. Among these, 80% were diagnosed by using four color flowcytometry (FACS Calibur), 9% and 11% via immunohistochemistry on bone marrow trephine biopsy samples and morphological examination respectively. RESULTS: The mean age of patients was 7.4 ± 4.3 years while male to female ratio was 1.75:1. Lymphoblastic leukaemia accounted for 77.2% and myeloid leukaemia 21.2%. Amongst lymphoblastic lineage, B-ALL was 80.4% while T-ALL was 19.6%. Among the phenotypic expression of B-ALL, CD79a (99.8%) had the highest positivity. In B-ALL, CD13 (29.8%) was the most common aberrant myeloid marker. Aberrant expression of CD79a observed in 11.1% of T-ALL cases. In non APL AML, aberrant expression of CD79a and CD19 was observed in 6.6% and 5.5% of cases respectively. CONCLUSION: Overall immunophenotypic profile, expression of aberrant phenotypes and subtype distribution in our patients was similar to international literature except for a relatively high frequency of T-ALL which was discordant from the western data.

Burkitt Lymphoma With Aberrant Immunophenotype Imposing Diagnostic Challenge.

BACKGROUND: Burkitt lymphoma (BL) exhibits a characteristic immunophenotype that is positive for pan-B-cell antigens and germinal center markers while negative for immature markers. A deviation from classic immunophenotype can cause diagnostic confusion and might result in false exclusion of BL. In some cases, overlapping clinical, morphological and immunophenotypic features of BL and B lymphoblastic lymphoma (B-LL) can be of diagnostic challenge. However, definitive delineation is of paramount importance due to difference in treatment. We describe a case of BL in a child with atypical features including absence of L3 morphology in diagnostic tissue and aberrant expression of CD34, CD99 and BCL2 on immunohistochemistry. These findings led to the interpretation of B-LL which was later on excluded by detection of t (8;14). This unorthodox case not only highlights the importance of cytogenetic testing but also emphasizes the correlation of all the diagnostic tools before making a definitive diagnosis. Therefore, reporting this case will help in eliciting the high index of suspicion among pathologists for this exceptionally unusual immunophenotype.

Her-2/neu Oncogene Amplification by Fluorescence In Situ Hybridization and Protein Overexpression on Immunohistochemistry in Breast Cancer.

OBJECTIVE: To investigate the concordance and discordance between the test results of Her-2/neu by immunohisto-chemistry (IHC) and flourescence In Situ hybridization (FISH) in breast cancer cases. STUDY DESIGN: Descriptive cross-sectional study. PLACE AND DURATION OF STUDY: Department of Histopathology, Dr. Ziauddin Hospital, Karachi, from 2011 to 2016. METHODOLOGY: Forty-three specimens of invasive ductal carcinoma of breast were evaluated for grade and Her-2/neu status using IHC and FISH methods. Concordance and discordance between their results was determined. RESULTS: There is 100% concordance between FISH and IHC in cases scoring 0, 1+ (negative) and 3+ (positive) immunostaining. Tumour cases scoring 2+ immunostaining showed amplification in 69.2% cases. All grade-I tumours were non-amplified on FISH, while most of the grade-III tumours showed Her-2/neu amplification on FISH. There is significant association of Her-2/neu IHC with tumour grade and FISH (p<0.05). A fairly high proportion i.e. 69.7% of cases showed Her-2/neu gene amplification. There was high concordance between Her-2/neu testing on IHC and FISH, (Kappa co-efficient 0.466, p <0.001). CONCLUSION: Her-2/neu amplification increases with increasing grade of breast cancer. A high proportion of Her-2/neu gene amplified cases indicates aggressive disease in that area and need for FISH testing on large scale, which is the gold standard for equivocal cases on immunohistochemistry.

Invasive Ductal Carcinoma: Correlation of Immunophenotypic Features with Age.

OBJECTIVE: To evaluate the frequency of hormone receptors and Her2neu expression and their correlation with age in patients of carcinoma breast. STUDY DESIGN: Descriptive, cross-sectional study. PLACE AND DURATION OF STUDY: Department of Histopathology, Dr. Ziauddin Hospital, Karachi, between the period 2006 - 2013. METHODOLOGY: Estrogen receptors, progesterone receptors and Her2neu immunohistochemical staining was performed on all specimens of carcinoma breast of female patients. Allred scoring was followed using normal epithelium as internal control. Age was determined in years. Results were described as percentages. RESULTS: Three hundred and forty-six cases of infiltrating ductal carcinoma of breast between the age of 20 - 90 years (mean= 49 ±14 years) were studied. Seventy-nine (23%) cases were below the age of 40 years. ER +ve cases were 210 (61%), PR +ve were 190 (55%), and 78 (23%) were Her2neu +ve. Three were 12 (3%) triple positive cases and 58 (17%) triple negative cases. One hundred and seven (31%) cases were ER/PR+ve and Her2neu -ve. Most of the breast cancer cases were aged between 41 - 50 years. Estrogen receptor positivity was maximum between 41 - 60 years. Fifty percent cases of carcinoma breast below 30-year age were also ER positive. CONCLUSION: A high proportion of breast cancer in young Pakistani females is alarming. Younger age harbours aggressive clinicopathologic characteristics. There is a due need for identifying high risk individuals/families including BRCA1 and BRCA2 testings, biologically driven trials devoted specifically to this group.

Reticular type parotid myoepithelial carcinoma: an intriguing variant and mimicker.

Myoepithelial carcinoma, the malignant counterpart of benign myoepithelioma, is one of the rarest salivary gland neoplasms. It is composed almost exclusively of tumour cells with myoepithelial differentiation, characterized by infiltrative growth and potential for metastasis. We herein, report a case of myoepithelial carcinoma in a 50 years old male with reticular morphology. Reticular variant of myoepithelial carcinoma may be mistaken for a variety of benign and malignant epithelial and mesenchymal tumours including mixed tumour (pleomorphic adenoma), adenoid cystic carcinoma, basal cell adenoma and epithelial myoepithelial carcinoma. Complete surgical excision is the mainstay of therapy. The role of radiation therapy and chemotherapy is not yet established. Awareness of this variant is emphasized to prevent misdiagnosis.

Extraskeletal osteosarcoma.

A 50 years old male presented with ulcer and swelling in left leg for 2 years. X-ray showed soft tissue sarcoma and excision was done. A diagnosis of extraskeletal osteosarcoma was made. Extraskeletal osteosarcomas are rare malignant mesenchymal neoplasms. By definition, these are located in soft tissue without primary involvement of bone or periosteum. Since these tumours mimic other soft tissue tumours and tumour like conditions, radiology and histopathology along with tumour markers studies are important in diagnosis of this tumour.

Anaplastic large cell lymphoma: a flow cytometric analysis of 29 cases.

We report our experience with flow cytometric (FC) analysis of 29 cases of anaplastic large cell lymphoma (ALCL). Morphologic analysis of processed cytocentrifuged preparations demonstrated neoplastic cells in 28 cases. In 25 of these, an aberrant lymphoid population was detected by FC analysis. The majority showed high orthogonal light scatter, similar to monocytes or granulocytes. Of the antigens CD2, CD3, CD4, CD5, and CD7, 5 cases expressed 1, 8 expressed 2, 6 expressed 3, 3 expressed 4, and 3 expressed all 5. CD4 was expressed most commonly (20/25 [80%]), followed by CD2 (18/25 [72%]), CD3 (10/25 [40%]), and CD5 and CD7 (8/25 [32%] each). CD45 was expressed in 23 of 25 cases and CD13 in 7 of 9. Of 21 cases, 13 were anaplastic lymphoma kinase (ALK)+, all of which were CD4+, vs 5 of 8 ALK - cases (P = .042). Most ALCLs can be detected and characterized by multiparameter FC analysis. However, light scatter gating on typical lymphoid regions may yield false-negative results in a substantial number of cases.