The Frequency of Immunofluorescence Antinuclear Antibody Patterns and Extractable Nuclear Antigen: Experience From a Large Laboratory in Pakistan.

Background Autoimmune disorders have shown an increasing incidence in the last few years. The systemic response to the disorder is characterized by the expression of antinuclear antibody (ANA), which serves as the serological hallmark of autoimmunity. Its presence may indicate either a systemic autoimmune disease such as systemic lupus erythematosus (SLE), scleroderma, and polymyositis/dermatomyositis or an organ-specific condition such as autoimmune thyroiditis and hepatitis. The systemic response may vary from one individual to another in each population. Several specific autoantibodies are also found to be associated with specific rheumatic diseases. Aim We aim to report the frequency of ANA positivity, ANA immunofluorescence patterns, and the presence of extractable nuclear antigen (ENA) among the general Pakistani population from one of the largest laboratories in Pakistan. Material and methods A total of 1,966 blood samples from a random Pakistani population were included, who were referred by their physicians with suspicion of autoimmune disease. These blood samples were subjected to ANA testing by indirect immunofluorescence method, and subsequently, positive samples were further analyzed for ENA detection in the Section of Chemical Pathology, Department of Pathology at Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan. An ANA titer of ≥1:80 was taken as positive. ANA was divided into subgroups based on titer: negative, weakly positive (titer of 1:80 or 1:160), moderately positive (titer of 1:320 or 1:640), and strongly positive (titer of ≥1:1280). Further, the frequency of ANA in male and female participants was studied in different age groups (2 to <10, 10 to <20, 20 to <30, 30 to <40, 40 to <50, 50 to <60, 60 to <70, 70 to <80, and 80+ years). Results This study included 1,966 participants, out of which 1,100 (55%) were ANA-positive at a titer of ≥1:80. Out of these ANA positives, the proportion of weakly positive (titer of 1:80 or 1:160), moderately positive (titer of 1:320 or 1:640), and strongly positive (titer of ≥1:1280) were 48.7%, 2.6%, and 4.2%, respectively. The ages ranged from two to 91 years, with a mean age of 43.64 ± 17.4 years. Females (75.5%) showed predominance over males (24.5%) in all age groups, with a ratio of 3:1. The age group in which most ANA positivity was found was 30 to <40 years. Among 1,100 ANA-positive sera, 383 (34.8%) participants tested positive for at least one out of 15 ENA. The most frequent autoantibodies noticed were anti-recombinant Ro52 (Ro52) (19.8%), anti-Sjogren's syndrome type A (SSA) (17.2%), and anti-ribonucleoprotein (RNP) (13.3%). The most prevalent ANA patterns were nuclear homogeneous (27.7%), followed by nuclear speckled (26.5%). Conclusion The frequency of ANA positivity is high in the Pakistani population and differs in different sex and age groups.

Microsatellite Instability in Near East Sebaceous Neoplasms: Toward Improved Prediction.

Sebaceous neoplasms (SN) comprise a heterogeneous spectrum of tumors with different biological behaviors. In the Near-East Region (NER), microsatellite instability (MSI) in SN's development, and its correlation with the clinicopathologic features of tumors is not well elucidated. A cohort of 225 SN patients (40 benign SNs and 185 sebaceous carcinomas) from the NER was retrospectively reviewed. Clinical variables and available follow-up information were recorded. MSI proteins (MLH1, MSH2, MSH6, and PMS2) as well as P53, P16, EMA, CD8, and PDL-1 expressions were examined by immunohistochemistry. Detection of human papilloma virus was determined by polymerase chain reaction. Microscopic features such as mitotic count and tumor-infiltrating lymphocytes were documented. A minority of SNs from benign (n=2) or malignant (n=3) tumors in the NER exhibit MSI (2.2%). MSI is exclusively found in patients with extraocular lesions (back, n=5) and presented a poor outcome. Among these, PMS2 protein was mostly lost (average=80%, n=4). SN with MSI exhibited a significant increase in p53 expression, (average=62.10%, P=0.002). There was no significant correlation between MSI status and any of the following: PD-L1, CD8, p16, and human papilloma virus infection. Microscopically, SN with MSI show significantly higher mitotic count, cystic changes and increased tumor-infiltrating lymphocytes. MSI is rarely found in NER's SN. When detected, it is exclusively in extraocular SNs with minimal predicative microscopic features and worse outcome.

Utility of folate receptor alpha immunohistochemistry in cytology specimens of metastatic breast carcinoma, metastatic serous carcinoma of Müllerian origin, and primary lung adenocarcinoma.

BACKGROUND: Folate receptor alpha (FRA) overexpression by immunohistochemistry (IHC) has been shown to various degrees in histologic specimens from breast ductal carcinoma (DC), serous carcinoma of Müllerian origin (SCM), and primary lung adenocarcinoma (ADC) among others. Antifolate therapies have recently shown usefulness in FRA overexpressing malignancies. We assessed the feasibility for detecting FRA overexpression by IHC in cytologic cell blocks (CB) from the aforementioned carcinomas. METHOD: Cases of breast DC, SCM and lung ADC were included. The CB were immunostained with FRA employing mAb 26B.3.F2 (Biocare Medical, Concord, CA). FRA staining was scored qualitatively, by intensity, and staining area. RESULTS: 4/20 (20%) triple negative breast cancer (TNBC), 27/29 (93%) SCM, and 20/22 (91%) lung ADC showed positive FRA immunoreactivity. All ER/PR positive (n = 5) and Her2-neu positive (n = 5) DC were negative with FRA IHC. CONCLUSIONS: FRA expression can be detected with a higher degree of confidence in SCM (93%) and lung ADC (91%) in CB, and to a lesser degree in TNBC. Our data also shows that FRA expression by IHC was more frequently associated with TNBC (20%) when compared with ER/PR positive or Her2neu positive breast cancers. FRA overexpression detected by IHC in CB is highly concordant with the published results of surgical specimens from SCM and lung ADC and less so from TNBC. Hence, IHC FRA analysis can be performed in the CB preparation with a high degree of confidence in SCM and lung ADC.

Folate Receptor Alpha Immunohistochemistry in Cytology Specimens of Metastatic Breast Carcinoma.

BACKGROUND: Folate receptor alpha (FRA) is involved in folate accumulation and utilization, and is expressed in varying proportions in breast, ovary and parotid epithelial cells, among others. FRA overexpression by immunohistochemistry (IHC) has been shown in estrogen/progesterone receptor (ER/PR)-negative carcinoma (40-74%) and in triple-negative breast carcinoma (TNBC; 50-86%) in histological specimens of primary breast cancers. We assessed the feasibility of IHC in detecting FRA expression and its patterns and clinical significance in metastatic TNBC in fine-needle aspiration (FNA) cell blocks (CBs). MATERIALS AND METHODS: Metastatic breast ductal carcinoma cases were retrospectively immunostained with FRA IHC on FNA CBs. FRA staining was scored qualitatively (+/-), by intensity (0-3) and by staining area (0-100%). Of these metastatic cases, a subset of primary breast carcinoma cases was also immunostained with FRA. The results were correlated with ER, PR and human epidermal growth factor receptor 2 (Her2/Neu) performed by routine IHC. RESULTS: A total of 40 FNA CBs with metastatic disease were studied, including hormone (ER/PR) positive (n = 5), triple positive (n = 5), Her2/Neu-only positive (n = 5) and TNBC (n = 25). FRA IHC showed immunoreactivity with moderate positivity in only 1 (4%) TNBC. All the remaining 39 cases were negative for FRA expression. Five cases of primary TNBC were stained with FRA IHC and were negative for FRA expression. CONCLUSIONS: Our data suggest that FRA expression by IHC was rarely associated with ER/PR-negative tumors relative to ER/PR-positive tumors and, more importantly, with TNBC in FNA CBs. This finding may have a clinical significance and prognostic implications in metastatic breast carcinoma. Furthermore, 5 primary TNBC cases did not overexpress FRA by IHC. Hence, antifolate receptor therapies do not appear to be clinically relevant in TNBC based on immunostaining of FNA CBs of metastatic breast cancers.

Myxoid Neoplasms.

Myxoid tumors of soft tissue constitute a heterogeneous group of neoplasms characterized by the presence of a myxoid stromal matrix, which appears on H&E as an amorphous material and may be confused with edema. Superficial myxoid lesions in general are benign and deep ones are malignant. Grossly, they have a variable gelatinous quality and overlapping histologic features that may present diagnostic difficulties for pathologists. Most are sporadic neoplasms, with only a small percentage arising in patients with hereditary disorders. Discussed are key features of classic myxoid lesions, histologic features, characteristic clinical presentations, immunohistochemical patterns, cytogenetic analysis, and differential diagnosis.