Faculty Bibliography

Introduction: Differentiating squamous cell carcinoma (SCC) from adenocarcinoma (ACA) can be challenging in cytology specimens. This distinction has major implications for lung carcinomas. We've been utilizing p63, and for the last 2 years, its n-terminally truncated variant, p40, to identify squamous differentiation. Recent literature showed p40 to have a better specificity for this purpose. We evaluated our experience to determine if p63 can be eliminated from our diagnostic panel to maximize cost savings and tissue preservation in cell blocks. Materials and Methods: 115 cytology cases of pulmonary ACAs and SCCs were identified with both p40 and p63 staining. All IHC was performed on cell blocks. Slides were scored for intensity and extent of staining using a 0- 3+ scale (intensity: 0, none; 3+, equivalent to positive control; extent/ percent of tumor cells staining: 0: none; 1+: 1-25%; 2+: 25-50%; and 3+: 50-100%). Results: Table 1 depicts our results. All SCCs and adenosquamous carcinomas (100%) were positive for both p40 and p63 regardless of specimen site. Overall, 15% of ACAs were positive for p40, and 16% were positive for p63, regardless of specimen site. Eleven percent (11%) of ACAs were positive for p40 in lung FNAs, and 21% were positive for p63. ACAs in effusion specimens resulted in more cases with p40 positivity (28%) compared to lung FNAs; this was not the case for p63 (21% in lung FNAs versus 11% in effusions). Conclusions: Our results demonstrate that p40 and p63 antibodies stain all SCCs in cytology specimens. However, despite prior reports claiming superior results for p40, we found that p40 yields a discernible level of false positivity in lung ACAs similar to p63. False positive rate for p40 in ACAs is highest in effusions and is not negligible. Therefore, it is not clear if p40 is preferable to p63 in cytology specimens. (Table Presented)

Introduction: The Bethesda System (TBS) uses a two-tiered approach to cervical squamous intraepithelial lesions (SILs). Occasionally, Paps with evident low grade SIL (LSIL) also have some features suggestive but not diagnostic of high grade SIL (HSIL). These Paps in our and other institutions are reported as 'LSIL, Cannot Exclude HSIL' (LSIL-H). LSIL-H has been shown to represent an intermediate risk (between LSIL and HSIL) for harboring a high grade lesion/carcinoma (HGD+) on biopsy. However, TBS 2014 continues to discourage its use to prevent the re-emergence of a threetiered reporting system. We review our experience with LSIL-H and discuss the best approach to report such Paps if the LSIL-H category is abandoned. Materials and Methods: Abnormal Paps were identified between January and June 2014 which had surgical follow-up within six months. Their biopsy outcomes were compared. Statistical analysis was performed using the Fisher's exact test. Results: Table 1 summarizes surgical diagnoses for each abnormal Pap category (total n=571). The differences in detection rates of HGD+ between LSIL and LSIL-H Pap was significant (p=0.000), whereas between LSIL-H and 'Atypical squamous cells, cannot exclude HSIL' (ASC-H) was not (p=0.101). If the LSIL-Hcategory is abandoned and LSIL-Hcases are reported as ASC-H, the rate ofHGD+ for theASC-H categorywould decrease from 55% to 41% (p=0.3). Alternatively, if LSIL-H cases are downgraded to LSIL, the rate of HGD+ for the LSIL category would rise from 7% to 9% (p=0.27). Conclusions: The 'LSIL-H' category indeed detects more HGD+ than LSIL, and fewer HGD+ than ASC-H. If LSIL-H is eliminated, Paps with this finding are best reported as ASC-H to ensure that women with potential HGD+ undergo colposcopy in a timely manner. Reporting LSIL-H as LSIL may delay colposcopy since management of LSIL Pap depends on multiple factors (age, HPV status, etc). (Table Presented)

Microcystic/reticular schwannoma is a recently described variant of schwannoma with a predilection for the gastrointestinal tract, rarely involving the head/neck region. This is the first reported case involving the submandibular gland. We present a case in a 34 year old man with 4.5 cm submandibular mass. Fine needle aspiration suggested a spindle cell lesion. Frozen section evaluation raised the possibility of mucoepidermoid carcinoma. Resection showed a well circumscribed mass with a mucoid appearance. Histologic findings include a lobular architecture with fibrous septa, a lympho-plasmacytic infiltrate, and scattered lymphoid aggregates at the periphery. There are two distinct histologic patterns with solid areas of spindle cells and areas of spindle/ovoid cells with a microcystic pattern in a myxoid background. The tumor has a pushing border, with extension into adipose and adjacent parenchyma, without cytologic atypia or necrosis. Immunohistochemical stains are positive for S-100 and CD34, and negative for calponin, mammoglobin, ALK1, p63, ER, GFAP, SMA, desmin, cytokeratin 7, cytokeratin AE1/AE3, and C-Kit. Mucicarmine stain is negative. Recognition of this benign unusual variant of schwannoma is paramount for appropriate conservative treatment due to the morphologic and immunohistochemical overlap with primary salivary gland carcinomas.

Introduction: ThinPrep and SurePath are two widely used liquid-based cervical cytology preparation techniques. SurePath has a lower unsatisfactory rate, but is not approved by the FDA for human papillomavirus testing. For this reason, our laboratory switched to ThinPrep and had a markedly increased unsatisfactory rate (up to 7%) due to lubricants, blood/inflammation, and insufficient cellularity. Our SurePath unsatisfactory rate was less than 1%. Our patient population has limited access to care and restricted flexibility in scheduling gynecologic appointments. Glacial acetic acid treatment for bloody specimens is time-consuming and repeat Thinprep slides did not yield significant improvement. Materials and Methods: The residual samples from 270 specimens initially deemed unsatisfactory were reprocessed by removing methanol fixative with washes of Hank's balanced salt solution via centrifugation and resuspension in SurePath preservative. Specimens were then processed according to standard SurePath methodology and demonstrated preserved cellular morphology. Results: 168 cases (62%) were adequate specimens after reprocessing, yielding 163 negative for intraepithelial lesion (NILM) (97%), 4 atypical squamous cells of undetermined significance (ASCUS) (2.4%) and 1 low grade lesion (0.6%). 105 unsatisfactory cases were due to blood (43%), lubricant (20%), scant cellularity (29.5%), inflammation (4.8%), and blood/ lubricant (3%). Follow-up repeat cervical cytology for unsatisfactory specimens in 78 of 102 women demonstrated 12 unsatisfactory specimens, 59 NILMs, 6 ASCUS, and 1 low-grade lesion. Conclusion: SurePath technique utilizes a density reagent which acts as an effective filter to eliminate obscuring factors such as blood, lubricant, and inflammation, without increasing our unsatisfactory rates. With ThinPrep, the unsatisfactory rate is much higher. We processed ThinPrep specimens using SurePath methodology after the methanol fixative was removed. Well preserved cellular morphology and enriched cellularity was achieved. Reprocessing unsatisfactory ThinPrep with the SurePath density reagent is an effective way to decrease the unsatisfactory rate in cervical cytology specimens

Introduction: Metastatic neoplasms (MN) are rare in the pancreas. An accurate diagnosis is challenging because MNs mimic primary pancreatic neoplasms, both clinically and on cytology. However, the distinction is critical for patient management. In this study, we reviewed our experience in diagnosing MNs by EUS-FNA of the pancreas. Material and Methods: We searched our database for pancreatic EUS-FNA specimens with a diagnosis of MN from 1994 to 2014. The clinical history, radiologic findings and follow-up of these cases, if available, were reviewed. Results: There were 17 cases of MNs to the pancreas in 7 males and 10 females, ranging in age from 37 to 85 years (mean = 62). The primary malignancies included carcinomas of the lung (4), colon (3), breast (2), ovary (1), kidney (1), liver (1), melanoma (3) and sarcoma (2). The pancreatic head and neck were the most common locations (73%).16 cases (94%) had a known prior history of malignancy; the clinical history was not provided in one case. All cases presented as a single mass in the pancreas. The average tumor size was 1.9 cm (range: 0.5 - 4 cm). 12 cases (71%) were poorly-differentiated carcinomas, indistinguishable from a pancreatic adenocarcinoma without immunohistochemical (IHC) studies and/or clinical history. 12 (71%) cases were correctly diagnosed as MN, 3 (18%) cases had indeterminate tumor origin, and 2 (12%) were misdiagnosed as primary pancreatic adenocarcinoma. A correct diagnosis was reached by cytomorphology alone in 3 cases (18%); morphology and immunohistochemical stains in 7 cases (41%); and morphologic comparison to the prior tumors in 2 cases (12%). Conclusions: EUS-FNA is an effective approach to diagnose pancreatic tumors. MNs can be difficult to differentiate from primary pancreatic carcinomas based on cytology alone. Clinical history and adequate cell block for IHC studies are essential to reach an accurate diagnosis