Abstracts

P41. ESTROGEN RECEPTOR AND PROGESTERON RECEPTOR AS POTENTIAL PROGNOSTIC IMMUNOHISTOCHEMICAL MARKERS AND THEIR ASSOCIATION WITH OUTCOME OF THYROID CANCER PATIENTS IN HOSPITAL KUALA LUMPUR

Aizat Aziz¹´² Fauzah Abdul Ghani1, Maizaton Atmadini Abdullah¹.

Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia¹. Pathology Department, Hospital Kuala Lumpur².

 

Introduction:

Recent studies have shown significant correlation between estrogen receptor(ER) and clinicopathological parameters of thyroid cancer. To date, there are no biochemical prognostic indicators available for thyroid cancer. In this study, we evaluated the potential of ER and progesterone receptor (PR) expression as prognostic markers in thyroid cancer and their correlation with clinicopathological parameters which include tumour size, metastasis, nodal involvement and clinical outcome.

Methods: 

This is a cross sectional study of 30 thyroidectomy cases from Hospital Kuala Lumpur   between 2015 and 2018. Archived paraffin-embedded tissue blocks were sectioned and stained with ER and PR antibodies. ER and PR expression were correlated with clinicopathological parameters using Spearman correlation analysis. 5-year survival rate of patients were analysed using Kaplan-Meier curve.

Results and Discussion:

ER and PR were expressed in 40% and 20% of thyroid cancer patients respectively. There was significant correlation between ER expression and larger tumour size, (rho=0.58, p<0.005) but PR expression showed no significant correlation (rho=0.163, p=0.389). The mean tumour size for ER positive was 3.45 cm, and 2.23 cm for ER negative cases. However, both ER and PR expression showed no significant correlation with lymph node involvement (rho=0.208, p0.135 for ER, and rho=0.036, p=0.424 for PR) and metastasis (for ER, rho=0.055, p=0.387, and for PR, rho=0.2, p=0.135). There was no linear association between expression of ER and PR with outcome of patients (p=0.625) and (p=0.064).

Conclusion:

Our findings are in keeping with other studies which reported positive correlation between ER and larger tumour size. Therefore, ER may be a poor prognostic indicator in thyroid cancer.

 

P42. INCIDENCE OF SUSPECTED LYNCH SYNDROME IN COLORECTAL ADENOCARCINOMAS USING A CLINICOPATHOLOGICAL SCREENING APPROACH IN HOSPITAL KUALA LUMPUR (HKL) : PRELIMINARY DATA

Sukanya Banerjee Nair¹, Subasri Armon1, Visalini Sanmugachandran², Mohd Razali bin Ibrahim², Mohd Fadzly Shahruddin¹

¹Department of Pathology, Hospital Kuala Lumpur, ²Department of General Surgery, Hospital Kuala Lumpur

 

Introduction:

Lynch syndrome is an autosomal dominant cause of familial colorectal adenocarcinoma. 15% of colorectal adenocarcinomas are associated with mismatch repair (MMR) deficiencies of which 3-5% are caused by inherited germline mutations while 10-12% are due to sporadic MLH1 promoter hypermethylation. A diagnosis of Lynch Syndrome indicates the need for surveillance of patients and their family members to detect early related malignancies. In view of the low sensitivity and high cost of selective germline testing, we employed National Comprehensive Cancer Network (NCCN) recommendations, reflex testing selective cases of colorectal adenocarcinomas by using clinicopathological criteria and an immunohistochemical (IHC) panel. This study describes the incidence of suspected Lynch syndrome in newly diagnosed colorectal adenocarcinomas using this approach.

Materials and Methods:

Paraffin sections of colorectal adenocarcinomas in HKL patients 60 years or younger or from the right colon or have poorly/undifferentiated/mucinous/signet ring morphology or with presence of marked tumour intraepithelial lymphocytes were reflex tested for MutL homolog 1 gene (MLH1), MutS protein homolog 2 gene (MSH2), MutS protein homolog 6 gene (MSH6) and PMS1 homolog 2 gene (PMS2) simultaneously using IHC. Cases that exhibited abnormal/absent staining for any one or pair of MMR proteins indicate biallelic loss-of-function mutations. Results were interpreted as a panel to determine the likelihood of an inherited Microsatellite Instability-High (MSI-H) cancer. These patients were then referred for confirmatory germline mutation testing and genetic counselling.

Results and Discussion:

22 cases were screened from January to June 2019. One of these cases exhibited absence of staining for both MLH1 and PMS2, however further work up showed presence of a B-Raf proto-oncogene (BRAF) mutation indicating a sporadic cause. The other case showed absence of both MSH2 and MSH6 which is associated with a high likelihood of an inherited MSI-H cancer, requiring confirmation by germline testing.

Conclusions:

An incidence of 4.5% of colorectal adenocarcinomas in Hospital Kuala Lumpur has been found to have loss of IHC staining deemed suggestive of an inherited gene mutation associated with Lynch syndrome.

P43. MALIGNANT GASTROINTESTINAL NEUROECTODERMAL TUMOUR: A RARE ENTITY NOT TO BE MISSED

Fatin Izni Nazri @ Zamri¹, Annatasia Elizabeth Banoon Ningkan²  and Nik Raihan Nik Mustapha³   

¹,²Jabatan Patologi, Hospital Umum Sarawak, Kuching, Sarawak, Malaysia; ³Jabatan Patologi, Hospital Sultanah Bahiyah, Alor Setar, Kedah, Malaysia

Introduction:

Gastrointestinal neuroectodermal tumour (GNET, previously referred to as clear cell sarcoma-like tumour of the gastrointestinal tract) is a rare sarcoma that commonly affects the young to middle age group. It has been reported to arise mostly from the wall of small intestine, followed by stomach and large intestine. Nodal and distant metastases are often seen at the time of presentation. Compared to its nearest counterpart clear cell sarcoma of soft tissue, it also displays similar morphology with evidence of primitive neural phenotype, as well as exhibits EWSR1 gene rearrangement. However GNET lacks melanocytic differentiation, as demonstrated immunohistochemically and on ultrastructural level.

Clinical case:

A 49 year old male who presented with symptoms of gastric outlet obstruction due to a pre-pyloric tumour of the stomach. A subtotal gastrectomy was performed. Macroscopically, the tumour (55 mm in widest dimension) was circumferential and exophytic, involving the full thickness of gastric wall. It showed brownish hemorrhagic and necrotic cut surfaces. Microscopically the tumour was lobulated and nonencapsulated, formed by plump spindled to polygonal cells that were arranged in vague short fascicles and sheets. These cells display prominent cytoplasmic clearing with pleomorphic and vesicular nuclei. Mitotic activity was up to 12/5 mm2. There were many osteoclast-like giant cells (CD68+) dispersed throughout the tumour. Metastasis was present in one regional lymph node. This tumour was diffusely positive for vimentin, S-100 protein and SOX10. It was negative for HMB45, CD34, CD117, DOG-1, CD99, CD56, chromogranin, synaptophysin, actin and desmin.

Discussion:

GNET may be clinically confused with gastrointestinal stromal tumour. As such, awareness of this new entity and the recognition of the tumour morphology along with appropriate use of adequate panel of immunohistochemistry testing and molecular testing if necessary, is important as patients often present with metastasis.

P44. ORBITAL DIFFUSE LARGE B-CELL LYMPHOMA ASSOCIATED WITH CHRONIC INFLAMMATION IN A PATIENT WITH ORBITAL IgG4-RELATED DISEASE: A CASE REPORT

Sue Anida Azman¹, Huzlinda Hussin², Norhayati Omar¹

¹Histopathology Unit, Department of Pathology, Hospital Serdang, Jalan Puchong, 43000 Kajang, Selangor Darul Ehsan.

²Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan.

 

Introduction:

IgG4-related disease is a fibroinflammatory condition affecting various organ systems. Recently, association between IgG4-related disease and malignancy has been suggested.

Clinical case:

A 60 year-old man presented with bilateral eyes (BE) proptosis and blurring of vision since 2008. The first two biopsies from the left eye in 2010 and 2013 were reported as reactive fibroinflammatory process. Subsequent biopsy from the right eye in 2016 revealed all histopathological features of IgG4-related disease with abundant IgG4+ plasma cells and high IgG4+:IgG+ ratio, thus reported as ‘highly suggestive of IgG4-related disease’. The patient was started on steroid but later was withheld due to pulmonary tuberculosis.

In 2018, his symptoms became progressively worsened. The left eye biopsy shows nodules of lymphoid tissue with fibrotic stroma. The lymphoid nodules are composed of large lymphoma cells that are CD20+, CD79a+, PAX5+, Bcl6+, CD30+ (few) and EBER+. The cells also display high proliferation rate. Pathological diagnosis of ‘diffuse large B-cell lymphoma (DLBCL) associated with chronic inflammation’ was concurred.

Discussion:

The association between IgG4-related disease and malignancy, including lymphoma is controversial. Most lymphomas that occur in IgG4-related disease were reported in the Asian literature involving the orbit, predominated by low grade lymphomas. Our case is one of the few cases of higher grade DLBCL occurring in orbital IgG4-related disease. The most possible mechanism in this case is orbital lymphoma arising from IgG4-related disease, rather than de novo IgG4 expressing lymphoma.

P45. LOCALLY AGGRESSIVE POROCARCINOMA WITH PROMINENT PLASMACYTOID DIFFERENTIATION: A RARE SKIN ADNEXAL NEOPLASM WITH UNUSUAL HISTOLOGICAL FEATURES

Ikmal Hisyam Bakrin¹, Nadzrin Md. Yusof¹

¹Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Selangor

 

Introduction:

Porocarcinoma is a rare, malignant neoplasm of infundibulum part of sweat glands which represents only 0.005% of epithelial cutaneous neoplasms. It commonly occurs in elderly, with the mean age of 67 years old. Their localisation is unrelated to sweat-gland concentration and occurs mainly on the lower limbs. Here, we present a case of locally aggressive porocarcinoma with prominent plasmacytoid cells.

Clinical Case:

A 44-year-old female presented with a slow-growing left big toe swelling for one year that associated with on and off pain. The nail and nail bed were completely destroyed and replaced by a fungating and ulcerating tumour. Histological examination showed deeply infiltrative squamoid cell proliferation, arising from the ulcerated epidermis. The lesional cells are cuboidal to oval in shape, displaying mildly pleomorphic nuclei with little eosinophilic cytoplasm and appearing smaller than the adjacent non-neoplastic keratinocytes. There is presence of prominent plasmacytoid and occasionaly clear cell changes. Mitotic figures and necrosis en masse are apparent in areas. Perineural invasion is evident with no lymphovascular invasion noted. CEA and EMA decorate intracytoplasmic lumina. The bone and surgical margins are free from tumour.

Discussion:

The prominent plasmacytoid differentiation was never reported before in the English language literature. This feature is more suggestive of cutaneous myoepithelial tumour (CMT), knowing the capabilities of myoepithelial cells to differentiate into many cell types including plasmacytoid. Ductular formation is also another feature that can be seen in CMT. However, markers for CMT namely S100, SMA EMA, and GFAP are negative, making the latter diagnosis unlikely.