Introduction: Diffuse large B-cell lymphoma (DLBCL) is the most common aggressive type of non-Hodgkin lymphoma with variable clinical outcomes. The immunogenotypic features of this heterogeneous disease in Malaysia were not well characterized. Materials & Methods: In total 141 local series of DLBCL cases from UKM Medical Centre were retrospectively studied. Results: Of these cases, we classified our patients into two subtypes: 32.7% (37/113) GCB and non-GCB 67.3% (76/113) by Hans algorithm and the results showed strong agreement with the results by Choi algorithm (κ = 0.828, P<0.001). Survival analysis indicated significant difference in between GCB and non-GCB subtypes (P=0.01), elevated serum LDH (P=0.016), age more than 60-year-old (P=0.021) and the presence of B symptoms (P=0.04). We observed 12% DLBCL cases were CD5 positive and 81.8% of them died of the disease (P=0.076). Analysis on the dual expression of MYC/ BCL2 revealed that there is no significant difference in DE and non-DE groups (P=0.916). FISH study reported there were 9.22% (13/141) rearranged cases observed in our population at which highest frequency of BCL6 gene rearrangement (76.9%), followed by MYC (15.4%) and BCL2 (7.7%); no BCL10 and MALT-1 gene rearrangement found regardless of using TMAs or whole tissue samples. More cases of MYC protein overexpression observed compared to MYC translocation. Conclusion: Relatively lower frequency of GCB tumours and low gene rearrangement rates were observed in Malaysian population. A national study is therefore warranted to know better the immunogenotypic characteristics of DLBCL in Malaysia and their implications on the survival.
immunohistochemistry

Introduction: Placental metastasis from maternal malignancies is a rare occurrence with a significantly adverse prognosis on the mother with no known effect or established risk factors for the newborn. As such, characterization of these lesions is necessary to serve as a stepping stone for more exhaustive studies regarding this presentation. Case Summary : This is a case of a metastatic breast carcinoma in a mature singleton placenta in a 39 year old woman diagnosed with invasive breast carcinoma of no special type/invasive ductal carcinoma, not otherwise specified, during the second trimester of pregnancy. Also discussed are the immunohistochemistry studies done to confirm the origin of the tumor. A comparison of the ER, PR, and HER2/neu receptor status between the primary lesion and the placental metastasis was also done. Conclusion Pregnancy-associated breast cancer is a lesion that carries adverse prognosis for the mother because of the delay in diagnosis attributable to confusion of symptomatology. The pertinent problem in pregnancy-associated breast cancer with placental metastasis is the deficiency of the placenta to induce tumor metastasis away from itself.
Immunohistochemistry

Solid pseudopapillary neoplasm (SPN) is a rare pancreatic neoplasm. This case reports a 63-year-old female previously diagnosed with bilateral adrenocortical carcinoma post resection who presents with persistent epigastric pain. Suspicions for recurrence prompted diagnostics revealing retropancreatic and left suprarenal foci, both suspicious for malignancy. Resection of both tumors yielded a moderately to poorly differentiated retropancreatic carcinoma with differentials not limited to recurrence and pancreatic neuroendocrine tumor with a left suprarenal lymph node. Immunohistochemistry was then done and was consistent with SPN having a strong expression for b-catenin, vimentin, pancytokeratin. It was non-specific to melan-A and negative for chromogranin A, synaptophysin, inhibin-a and CD10. At 6 months’ follow up, patient is clinically well and abdominal CT scan showed no recurrence. SPNs can masquerade as other neoplasms having similar clinical, radiologic and histopathologic features. Immunohistochemistry thus plays a crucial role for accurate diagnosis and management. Surgical resection still remains the treatment of choice and can provide a 95% overall survival rate, while limited evidence supports the use of adjuvant chemotherapy or radiation.
Immunohistochemistry

No abstract available.
Immunohistochemistry ; Keratins

No abstract available.
Adenocarcinoma* ; Immunohistochemistry*

No abstract available.
Immunohistochemistry* ; Sciuridae*

Introduction: Extramammary Paget’s disease (EMPD) is a rare cutaneous slow growing tumor seen in areas rich in apocrine glands such as the anogenital region while ectopic EMPD is defined as EMPD arising on non-apocrine areas. The pigmented variant of EMPD is a very rare finding, with only a few reported cases, and can be misdiagnosed as melanoma. Case report: We report a case of a 74-year-old woman who presented with a four-year history of pruritic, non- healing erythematous plaques located on the right axilla and left lower abdomen. Histopathology revealed acanthotic epidermis with atypical keratinocytes that was negative for anti S-100 and Melan-A and was positive for carcinoembryonic antigen (CEA), cytokeratin (CK), CK 7 and epithelial membrane antigen (EMA). Patient was managed as pigmented and ectopic variant of extramammary Paget’s disease. Several tests and imaging were done to rule out malignancy. Wide excision with axillary node dissection, bilateral inguinal node dissection, frozen section biopsy and reconstruction using right pectoralis major musculocutaneous flap, split thickness skin graft with left inguinohypogastric drain were done by reconstructive surgery. Frozen section biopsy was negative for S-100, MELAN-A and HMB-45, ruling out malignant melanoma. Patient followed up every month for 6 months after the procedure with no recurrence and lymphadenopathy. Conclusion This case emphasizes that extramammary Paget’s disease is not a preventable disease and early diagnosis is the key to a favorable diagnosis. Any unilateral eczematous lesion that does not respond to an appropriate course of topical treatment warrants a skin biopsy.
Melanoma ; Immunohistochemistry

Dedifferentiated liposarcoma is a soft tissue sarcoma of adipocytic lineage. Histopathology and immunohistochemistry are essential for diagnosis. A 51-year-old Filipino woman presented with a rapidly enlarging left gluteal tumor. Histopathology revealed a multilobulated tumor having prominent myxoid stroma with numerous stellate-shaped, atypical cells bearing atypical mitotic figures. Other lobules were composed of sheets of pleomorphic cells, with atypical mitotic figures. The tumor stained positively with alcian blue, vimentin, MDM2 and p16 stains. Other immunohistochemical (IHC) studies done (pancytokeratin, CK7, CK 20, CD 34, CEA, desmin, EMA, SMA, S100) showed negative results. After a 2 cm wide excision of the sarcoma, patient was free from local tumor recurrence for 2 months, after which she was lost to follow-up. We report this case and a brief review of the current literature on dedifferentiated liposarcoma.
Liposarcoma ; Immunohistochemistry

Mutation of the p53 tumor-suppressor gene in exons 4 through 9 was examined in 34 cases of primary advanced gastric cancer using PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) and the results were compared with p53 protein expression as determined by immunohistochemistry (IHC) using a monoclonal antibody(DO-1). p53 protein detected by IHC was observed in 14 cases (41.2%) and genotypic mutation detected by PCR-SSCP in exons 4-9 was observed in 13 cases (38.2%) One case showed an aberrant band on PCR-SSCP both in Exon 7 and Exon 8/9. p53 alteration detected by either IHC or PCR-SSCP was observed in 19 cases (55.9%), but only 8 cases (23.5%) showed both p53 mutation and protein expression. We also tried to obtain the correlation between relative intensity of the shifted bands on PCR-SSCP and percentage of positive cells by IHC, but a significant correlation was not seen between relative intensity of shifted bands on PCR-SSCP and positve cell ratio. A discrepancy between p53 protein expression and p53 mutation is observed in primary gastric carcinomas. The reason for this discrepancy are not apparent. However, examination of gastric carcinomas for mutations in other exons may identify a better correlation with protein overexpression. The results obtained in this study suggest that the negative reaction for p53 immunohistochemistry may not necessarily mean no genetic alteration of the p53 locus.
Exons ; Immunohistochemistry* ; Stomach Neoplasms

No abstract available.
Female* ; Humans ; Immunohistochemistry*