Differential expression of various clones of estrogen receptor in cell block preparation of lung adenocarcinoma.

BACKGROUND: Women treated for breast cancer are at increased risk of developing pulmonary nodules which could represent new primary lung carcinomas or metastatic breast carcinoma. The FNA biopsy is frequently the first diagnostic choice in determining the primary site of the tumor. Estrogen receptor (ER) positivity in diagnostic tissue is generally used to favor breast over lung primary. However, the recent studies have shown a wide range of ER antibody cross reactivity with lung adenocarcinoma. We studied the frequency of ER expression in cytology samples of lung adenocarcinoma using antibodies to three different ER clones. METHODS: Cytology cell block preparations, including 22 lung FNAs and 19 malignant pleural effusions (PE) from 41 patients, with clinically documented primary lung adenocarcinomas were selected for this study. All cases were stained with monoclonal antibodies to ER clones 6F11 and 1D5. Twenty nine cases with remaining available material (15 FNA and 14 PE) were stained with a third antibody to ER clone SP1. The extent of ER nuclear staining was scored as 3+ (50%-100% of tumor cells), 2+ (11%-49%), and 1+ (≤10%). RESULTS: Positivity for ER-6F11 clone was present in 4 of 22 lung FNAs (18.2%, 2+ staining). Two of the four 6F11 positive FNAs also co-expressed ER-1D5 (9.1%, 2+ staining). No immunoreactivity was observed for ER clones 6F11 and 1D5 in all 19 malignant PEs. In addition, none of the remaining 15 FNAs and 14 PEs showed immunoreactivity for ER-SP1 clone. CONCLUSIONS: A small subset of pulmonary adenocarcinomas shows immunoreactivity for ER clones 6F11 and 1D5 in FNA samples (18.2% and 9.1%, respectively). The absence of immunoreactivity for ER-SP1 clone indicates higher specificity of this clone in non-breast tissue. The differential diagnostic value of all ER clones in malignant PEs appears to be secure. Larger studies are necessary to validate this observation.

Estrogen, progesterone, and HER-2 receptor immunostaining in cytology: the effect of varied fixation on human breast cancer cells.

The ASCO/CAP Expert Panel recommends that all invasive breast carcinomas and breast cancer recurrences be tested for ER, PR and HER-2 expression. The guidelines for testing of surgical specimens by immunohistochemistry (IHC) are well defined, whereas they are lacking for cytological samples. We evaluated various fixation protocols for optimal receptor testing by immunohistochemistry and immunocytochemistry (ICC) of human breast cancer cell lines MCF-7 (ER/PR positive) and SKBR-3 (overexpressing HER-2). The cells were fixed in 10% neutral buffered formalin or Saccomanno Fixative (SF) for various time points, and either embedded in paraffin as cell blocks or prepared as cytospins. ER and PR slides were assigned a proportion score (PS; 0-5), an intensity score (IS; 0-3) and a total score (TS = PS + IS). Standard DAKO scoring system ranging from 0 to 3+ was used for the evaluation of HER-2 staining. Human breast cancer cells stained successfully for ER, PR and HER-2 when fixed in formalin and prepared as cell blocks. The optimal fixation time for formalin-fixed cells ranged from 2 to 96 hours. Cells fixed in SF from 2 to 96 hours also stained well for ER and PR. However, SF produced variable results for HER-2 staining; particularly, SF fixation beyond 24 hours caused false negative results. The interpretation of HER-2 staining on cytospins was not feasible irrespective of the fixative and fixation time. In summary, formalin fixation from 2 to 96 hours and preparation of cells as cell blocks produces optimal results for ER, PR, and HER-2 testing in human breast cancer cells.

APTIMA assay on SurePath liquid-based cervical samples compared to endocervical swab samples facilitated by a real time database.

BACKGROUND: Liquid-based cytology (LBC) cervical samples are increasingly being used to test for pathogens, including: HPV, Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) using nucleic acid amplification tests. Several reports have shown the accuracy of such testing on ThinPrep (TP) LBC samples. Fewer studies have evaluated SurePath (SP) LBC samples, which utilize a different specimen preservative. This study was undertaken to assess the performance of the Aptima Combo 2 Assay (AC2) for CT and GC on SP versus endocervical swab samples in our laboratory. MATERIALS AND METHODS: The live pathology database of Montefiore Medical Center was searched for patients with AC2 endocervical swab specimens and SP Paps taken the same day. SP samples from CT-and/or GC-positive endocervical swab patients and randomly selected negative patients were studied. In each case, 1.5 ml of the residual SP vial sample, which was in SP preservative and stored at room temperature, was transferred within seven days of collection to APTIMA specimen transfer tubes without any sample or patient identifiers. Blind testing with the AC2 assay was performed on the Tigris DTS System (Gen-probe, San Diego, CA). Finalized SP results were compared with the previously reported endocervical swab results for the entire group and separately for patients 25 years and younger and patients over 25 years. RESULTS: SP specimens from 300 patients were tested. This included 181 swab CT-positive, 12 swab GC-positive, 7 CT and GC positive and 100 randomly selected swab CT and GC negative patients. Using the endocervical swab results as the patient's infection status, AC2 assay of the SP samples showed: CT sensitivity 89.3%, CT specificity 100.0%; GC sensitivity and specificity 100.0%. CT sensitivity for patients 25 years or younger was 93.1%, versus 80.7% for patients over 25 years, a statistically significant difference (P = 0.02). CONCLUSIONS: Our results show that AC2 assay of 1.5 ml SP samples transferred to APTIMA specimen transfer medium within seven days is sufficiently sensitive and specific to be used to screen for CT and GC. CT sensitivity may be somewhat reduced in samples from patients over 25 years. SP specimens retained in the original SP fixative for longer time intervals also may have decreased sensitivity, due to deterioration of RNA, but this was not assessed in this study. The ability to tap the live pathology database is a valuable tool that can useful to conduct clinical studies without a costly prospective clinical trial.

Check Sample Abstracts.

The following abstracts are compiled from Check Sample exercises published in 2008. These peer-reviewed case studies assist laboratory professionals with continuing medical education and are developed in the areas of clinical chemistry, cytopathology, forensic pathology, hematology, microbiology, surgical pathology, and transfusion medicine. Abstracts for all exercises published in the program will appear annually in AJCP.

HepPar1, MOC-31, pCEA, mCEA and CD10 for distinguishing hepatocellular carcinoma vs. metastatic adenocarcinoma in liver fine needle aspirates.

OBJECTIVE: To investigate immunohistochemical staining of hepatocyte paraffin-1 (HepPar1), alpha-fetoprotein (AFP), polyclonal carcinoembryonic antigen (pCEA), monoclonal CEA (mCEA), MOC-31 and CD10 for differential diagnosis of hepatocellular carcinoma (HCC) from metastatic adenocarcinoma (MA) on fine needle aspiration biopsy (FNAB). STUDY DESIGN: Fifty-one archival, paraffin-embedded FNAB cell blocks, representing 18 HCCs and 33 MAs, were immunostained with antibodies for AFP, CD10, pCEA, mCEA, HepPar1 and MOC-31. RESULTS: HepPar1, AFP, canalicular pCEA and CD10 were positive in 78% (14 of 18), 28% (5 of 18), 72% (13 of 18) and 35% (6 of 17) of cases of HCC, respectively. The 33 MAs were negative for immunostaining of the above antibodies except for one AFP-positive MA. Ninety-seven percent (31 of 32) of the MAs and 6% (1 of 17) of the HCCs were positive for MOC-31. Monoclonal CEA was immunoreactive on 82% (27 of 33) of the MAs and negative on all the HCCs. CONCLUSION: HepPar1 was the most sensitive marker for HCC, followed by canalicular staining for pCEA. For MA, MOC-31 was the most sensitive marker; mCEA was slightly less sensitive but more specific. We suggest using HepPar1, pCEA, CD10, MOC-31 and mCEA as a panel for distinguishing HCC from MA in liver FNAB.