Improved correlation of urinary cytology specimens using The Paris System in biopsy-proven upper tract urothelial carcinomas

BACKGROUND

Urine cytology specimens are essential for screening and monitoring high-grade urothelial carcinomas. However, inconsistent reporting and equivocal diagnostic categories have remained a challenge. The Paris System for Reporting Urinary Cytology (TPS) was developed to provide clear cytomorphologic criteria for urine cytology specimens. Significant correlation between the surgical biopsy diagnosis (SD) and TPS diagnosis (PD) has been established in lower urothelial tract carcinomas, but to the authors' knowledge limited information is available regarding upper urinary tract carcinomas.

METHODS

A total of 56 cytology specimens from 35 patients within 90 days of an SD of upper urinary tract carcinoma were included. Cytology was re-reviewed and assigned a PD. The original diagnosis (OD) and PD were compared with the corresponding SD to determine which correlated best.

RESULTS

The PD corresponded to the SD in 35 of 56 cases (63%), which was greater than that for the OD and SD, which were concordant in 19 of 56 cases (34%). Both the OD and PD were concordant in 18 of 56 cases (32%), and neither corresponded in 20 of 56 cases (36%). A total of 27 of 33 cases of high-grade urothelial carcinoma/carcinoma in situ on SD (82%) were identified using the PD whereas only 15 cases (45%) were identified with the OD. The number of "atypical" diagnoses in the OD was reduced from 16 of 56 cases (29%) to 7 of 56 cases (13%) using the PD. Of the 14 of 56 "negative" OD (25%), only 4 remained after implementation of the PD. A diagnosis of low-grade urothelial neoplasm was established in 6 of 20 cases (30%) with the PD compared with 3 of 20 cases with the OD (15%).

CONCLUSIONS

The authors found that reclassification with TPS improved correlation with the SD compared with previous methodologies. Specifically, TPS increased the number of high-grade urothelial carcinoma diagnoses and decreased the number of equivocal or "atypical" diagnoses. Cancer Cytopathol 2018. © 2018 American Cancer Society.

Laboratory management curriculum for cytopathology subspecialty training

Laboratory management should be an integral part of training in pathology residency and fellowships. Herein, we have outlined some basic laboratory management topics a graduating cytopathology fellow should be familiar with. An overview of regulatory agencies that have oversight over laboratory testing, cytopathology laboratory accreditation, pre-analytic, analytic and post-analytic quality assurance, billing/coding, basic statistics, verification/validation of testing, physician credentialing, board certification/maintenance of certification, and malpractice in cytopathology are addressed. This review is by no means all inclusive, but rather a guide to the basic management related topics to be covered during cytopathology subspecialty training.

Acquired myospherulosis secondary to gluteal augmentation on fine needle aspiration cytology: A diagnostic challenge

A 30-year-old female presented with a three-month history of a multilocular cystic lesion over the lumbosacral spine. Fine-needle aspiration biopsy (FNA) of the lesion was performed at an outside institution, and a cytologic diagnosis, suspicious for chordoma, was rendered. The patient presented for surgical consultation at our institution. Repeat FNA demonstrated an unusual fat-like material. Upon further inquiry, the patient provided a recent history of gluteal contour improvement with fibroadipose tissue implants. A diagnosis of myospherulosis was made with a concurrent surgical pathology correlation. No evidence of chordoma was identified. To date, this is the first reported case of acquired myospherulosis in the context of gluteal contour enhancement and represents an important diagnostic pitfall to consider on cytology preparations.

LEF-1: Diagnostic utility in distinguishing basaloid neoplasms of the salivary gland

BACKGROUND

Lymphoid enhancer binding factor 1 (LEF-1) has recently been reported as a potential immunohistochemical (IHC) marker for basal cell adenoma (BCA) and other salivary gland tumors, which may contribute to an increased accuracy in differentiating basaloid salivary gland neoplasms. We evaluated the utility of LEF-1 in fine needle aspiration (FNA) and resection specimens to distinguish pleomorphic adenoma (PA), BCA, basal cell adenocarcinoma (BCAC), and adenoid cystic carcinoma (ACC) as well as in non-neoplastic salivary gland (NNSG).

METHODS

Cases including 66 PA (35 FNA, 31 resections), 12 BCA (5 FNA, 7 resections), 42 ACC (11 FNA, 31 resections), 1 BCAC FNA, and 10 NNSG (5 FNA, 5 resections) were obtained and stained for LEF-1.

RESULTS

On cell block (CB), 51% of PA and 60% of BCA were LEF-1 positive while 91% of ACC were LEF-1 negative. Among resections, there was a higher percentage of LEF-1 positive PA (84%) and BCA (86%), and a higher percentage of LEF-1 negative ACC (97%). LEF-1 staining had a low to moderate sensitivity for detecting benign basaloid neoplasms on FNA CB and resection specimens (52.5% and 84%, respectively), but a higher specificity (92% and 97% respectively), and positive predictive value (95% and 97% respectively).

CONCLUSION

When comparing benign (PA and BCA) and the most common malignant basaloid salivary gland tumor (ACC), positive LEF-1 favors a benign neoplasm. Additional studies with LEF-1, specifically including other rare basaloid salivary gland neoplasms are needed to further clarify the role of LEF-1 in diagnosing these lesions on FNA.

MYC Immunohistochemistry Predicts MYC Rearrangements by FISH

MYC is the proto-oncogene classically associated with Burkitt lymphoma (BL) located at chromosomal locus 8q24. Rearrangements of MYC are seen in nearly 100% of BL but have been reported in 3–16% of diffuse large B-cell lymphomas (DLBCLs). Rearrangements of MYC are tested for by flourescence in situ hybridization (FISH). In this study, we compared immunohistochemistry (IHC) using a monoclonal antibody directed against the human Myc protein to the current method, FISH. 31 cases were identified that had been tested for MYC rearrangements by FISH over 27 months with heterogeneity in the diagnoses: 5 BL; 10 DLBCL; 3 B-cell lymphoma unclassifiable between DLBCL and BL; 5 B-cell lymphoma not otherwise specified; 1 EBV-related B-cell lymphoma; 1 composite CLL/SLL-large cell lymphoma; and 6 designated as high-grade or aggressive B-cell lymphoma. Analysis by FISH was performed as part of the clinical workup, where a MYC rearrangement is defined as a split fusion signal in at least 5.7% of cells. Myc-IHC was interpreted as a qualitative positive (overexpressed) or negative (not overexpressed) result. 12 cases (39%) were positive for MYC rearrangements by FISH. Overall, 13 cases (42%) showed Myc overexpression by IHC, 11 of which harbored a MYC rearrangement by FISH. There were two false positives and one false negative. Thus, Myc-IHC predicted a MYC rearrangement by FISH with 92% sensitivity and 89% specificity. We can thus conclude that Myc-IHC should be a potentially useful screening tool for identifying lymphomas that may harbor a MYC rearrangement.

Double staining: diagnostic utility in non-small cell lung carcinoma in the era of tissue conservation

INTRODUCTION

In an era of precision medicine distinguishing pulmonary squamous cell carcinoma (SQCC) from adenocarcinoma (ADC) is vital for treatment. Immunohistochemical (IHC) staining for p40, p63 and Cytokeratin 5 (CK5) are useful for SQCC, while TTF-1 and Napsin-A can be used for confirming ADC. Fine needle aspiration (FNA) cell blocks (CB) have limited tissue, hence, double IHC staining is helpful for tissue conservation for molecular analysis.

MATERIALS AND METHODS

Thirty six confirmed lung SQCC and 45 ADC CB were selected for IHC. Double staining was performed with p40/CK5 and p63/CK5 on all SQCC, and with TTF-1/Napsin-A on all ADC. Results were positive if at least 5% of malignant cells were immunoreactive for the antigen.

RESULTS

P40/CK5 had (92%) sensitivity, (100%) specificity, (100%) positive predictive value (PPV), (91%) negative predictive value (NPV) and an overall diagnostic accuracy of (96%). By contrast, P63/CK5 double stains showed (92%) sensitivity, (80%) specificity, (85%) PPV, (89%) NPV and (86%) overall diagnostic accuracy, respectively. TTF-1/Napsin A staining for ADC showed a sensitivity of 80%, specificity of 96%, PPV of 97%, NPV of 71% and accuracy of 85%.

CONCLUSION

P40/CK5 double stain has higher specificity, PPV, NPV, and overall accuracy than P63/CK5 double stain in the diagnosis of lung SQCC. TTF-1/Napsin-A double staining is a valuable marker with high specificity, PPV, and diagnostic accuracy in diagnosing lung ADC. The usage of P40/CK5 and TTF-1/Napsin-A as a panel can be recommended for characterizing non-small cell carcinoma (NSCC) of the lung and for conserving tissue for molecular testing.

Nodular oncocytic hyperplasia: Can cytomorphology allow for the preoperative diagnosis of a nonneoplastic salivary disease?

BACKGROUND

Nodular oncocytic hyperplasia (oncocytosis) of the salivary glands is a benign process that does not inherently require surgical excision. However, cytologic findings in fine-needle aspiration (FNA) of oncocytosis cases have not been well characterized previously, limiting preoperative identification.

METHODS

All available cases of oncocytosis with corresponding FNA specimens were identified from the pathology archives of 3 academic institutions. Clinical, cytologic, and histologic findings were tabulated for all cases.

RESULTS

Twelve cases of oncocytosis were identified from 11 patients, including 11 parotid FNA specimens and 1 submandibular FNA specimen. On the original diagnoses, 6 specimens were classified as benign, 4 as atypical, and 2 as nondiagnostic. Oncocytosis was listed in the differential diagnosis in only 1 case. Among diagnostic aspirates, 8 demonstrated low cellularity and 2 demonstrated moderate cellularity. All 10 cases demonstrated oncocytic cells in small to medium groups, with single cells in just 1 case. Spindled and squamous morphology were each noted in 3 cases. Four cases demonstrated cystic change and 1 showed background mucin without goblet cells. No necrosis or mitoses were observed.

CONCLUSIONS

Although oncocytosis demonstrates some overlap with Warthin tumor and oncocytoma, it lacks the diagnostic findings specific to oncocytic salivary gland malignancies such as salivary duct carcinoma, acinic cell carcinoma, mammary analog secretory carcinoma, and mucoepidermoid carcinoma. Despite current limitations in the understanding of oncocytic salivary gland lesions, the presence of a paucicellular specimen comprised of small groups of oncocytic cells should raise the possibility of oncocytosis in the differential diagnosis and can favor it in elderly patients with multiple salivary nodules. Cancer Cytopathol 2017;125:627-34. © 2017 American Cancer Society.

Fine Needle Aspiration of Langerhans Cell Histiocytosis: A Cytopathologic Study of 37 Cases

OBJECTIVE

Langerhans cell histiocytosis (LCH) is an uncommon neoplasm of dendritic cells and predominantly occurs in children and young adults. The study aims to evaluate cytopathologic features and current diagnostic concepts in a large series of LCH on fine needle aspiration (FNA).

STUDY DESIGN

We retrospectively searched the pathology archives of The Johns Hopkins Hospital (JHH) and Emory University Hospital (EUH) to identify all FNA cases diagnosed as LCH in a period of 21 years. Cytologic material and immunohistochemical stains were reviewed.

RESULTS

A total of 37 LCH patients (26 from JHH and 11 from EUH) with FNA diagnoses were identified. The sites of LCH included bone in 28, soft tissue of head and neck in 6, and lymph nodes in 3. Thirty-one patients (84%) were diagnosed as LCH, 4 (11%) had a descriptive diagnosis suggesting scant cellularity with epithelioid/histiocyte-like cells and mixed inflammation, and 2 (5%) were non-diagnostic due to insufficient cellularity. Immunohistochemical stains were performed on cell block sections in 26 cases, showing 24 of 24 (100%) positive for CD1a, 22 of 23 (96%) positive for S100-protein, and 3 of 3 (100%) positive for CD68.

CONCLUSIONS

LCH can be accurately diagnosed in FNA based on the characteristic cytomorphology and selected immunohistochemistry. Diagnosis may be difficult in cases with scant or insufficient cellular material.

Predicting histological subtypes of follicular variant of papillary thyroid carcinoma based on cytomorphology. Can cytomorphology optimize use of molecular testing?

INTRODUCTION

Follicular variant papillary thyroid carcinoma (FVPTC) can be further subclassified into one of 3 subtypes: non-invasive encapsulated FVPTC, invasive encapsulated FVPTC, and infiltrative FVPTC. Longitudinal and molecular studies have demonstrated that, in terms of both molecular profiles and prognosis, encapsulated FVPTC is comparable to follicular adenoma, invasive FVPTC to follicular carcinoma, and infiltrative FVPTC to classic PTC. To improve triaging and prevent overtreatment of patients with FVPTC, we sought to determine cytologic features likely to occur within each subtype.

METHODS

A laboratory database search from 2010-2015 was conducted to identify patients with biopsy-proven FVPTC and prior fine-needle aspiration. Surgical specimens were reviewed to determine the appropriate subcategorization. Accompanying cytology reports were reviewed for features common in classic PTC and follicular neoplasms.

RESULTS

Encapsulated variants were more likely to be graded as Bethesda category 4 compared with invasive or infiltrative variants. In contrast, infiltrative variants were more likely to be graded as Bethesda categories 5 and 6 compared with invasive or encapsulated variants. Compared with the encapsulated variant, infiltrative FVPTC was more likely to have nuclear pseudo-inclusions (31.82% versus 8.11%, P = 0.0468) and less likely to have microfollicular architecture (22.73% versus 54.05%, P = 0.0374).

CONCLUSION

This study identified cytomorphologic differences between encapsulated and infiltrative FVPTC. With a higher threshold of suspicion for FVPTC, improved awareness of the differences between these subtypes and incorporation of molecular testing, it is likely that the Bethesda category can be revised and patient triaging can be significantly improved.

Stromal PD-L1 Expression Is Associated With Better Disease-Free Survival in Triple-Negative Breast Cancer

OBJECTIVES

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer, and there is no approved targeted therapy. We studied the expression of programmed cell death protein 1 (PD-1) and its ligand (PD-L1) in TNBC.

METHODS

Full-face sections from 136 TNBC cases without neoadjuvant therapy between 2004 and 2013 were stained and evaluated for immune cell PD-1 staining and stromal or tumoral PD-L1 staining using the H-score (staining percentage × intensity). Nottingham histologic grade, lymphovascular invasion (LVI), mitotic count, and tumor-infiltrating lymphocytes (TILs) were evaluated. Tumor size, lymph node status, Ki-67 score, metastasis, overall survival (OS), and disease-free survival (DFS) were retrieved from medical records.

RESULTS

Of the 136 TNBC cases, 69 (51%) had any PD-L1 staining and 35 (26%) had PD-L1 staining with an H-score of 5 or more; 117 (86%) had any PD-1 staining and 68 (50%) had PD-1 staining with an H-score of 5 or more. Tumor size and LVI were significantly associated with worse OS and DFS, and TILs and LVI were significantly associated with metastasis in univariate analysis. Stromal PD-L1 expression was significantly associated with better DFS in multivariate analysis. PD-1 expression was not associated with DFS, OS, or metastasis.

CONCLUSIONS

PD-L1 expression is seen in a high proportion of TNBCs and associated with better DFS.

PLAG1: An Immunohistochemical Marker with Limited Utility in Separating Pleomorphic Adenoma from Other Basaloid Salivary Gland Tumors

OBJECTIVE

Fine-needle aspiration (FNA) diagnosis of salivary gland neoplasms is often challenging. Differentiating between pleomorphic adenomas (PA) and other basaloid neoplasms, especially basal cell adenoma (BCA) and adenoid cystic carcinoma (AdCC), can be difficult in cellular aspirates. PLAG1 (PA gene 1) is a proto-oncogene, which is frequently rearranged in PAs, leading to the aberrant expression of its protein. PLAG1 IHC expression has been reported to be positive in most PAs. The aim of this study was to evaluate the sensitivity and specificity of PLAG1 to differentiate PA from other basaloid neoplasms.

STUDY DESIGN

Immunohistochemical evaluation of PLAG1 was performed on 125 cases (52 FNAs and 73 surgical excisions). Nuclear staining of tumor cells was scored by the intensity and percentage of positive tumor cells. A combined score of >5 was defined as positive.

RESULTS AND CONCLUSION

The sensitivity (55%) and specificity (75%) of PLAG1 in diagnosing PA in FNAs is relatively modest thus limiting its diagnostic utility. BCAs and AdCCs showed PLAG1 false positivity, in surgical excision specimens and less so in FNAs. This may be due to limited sampling or tumor heterogeneity. Hence, PLAG1 is a modest marker for PAs in FNAs.

Cytomorphologic characteristics and differential diagnoses of lymphoepithelial carcinoma of the parotid

INTRODUCTION

Lymphoepithelial carcinoma of the salivary gland is an extremely rare neoplasm and is challenging to diagnose by fine needle aspiration (FNA). There are rare reports on the cytopathologic features of lymphoepithelial carcinoma, which may be mistaken for other high-grade salivary gland neoplasm or a metastasis to the salivary gland.

MATERIALS AND METHODS

A retrospective review was undertaken of 7 cases of lymphoepithelial carcinoma of the parotid diagnosed on FNA with histologic confirmation from 4 major medical centers.

RESULTS

Cytomorphologic features of lymphoepithelial carcinoma include smears with moderate cellularity displaying a rich nonneoplastic population of lymphoplasmacytic cells admixed with tissue fragments of high grade, malignant undifferentiated epithelial cells with high nuclear to cytoplasm ratio, hyperchromasia, prominent nucleoli, and scant to abundant, indistinct cytoplasm.

DISCUSSION

Diagnostic pitfalls of lymphoepithelial carcinoma include metastatic squamous cell carcinoma, metastatic nasopharyngeal carcinoma, and other high grade primary salivary gland neoplasms. Recognizing this lesion may help guide clinicians to perform additional imaging studies to exclude a primary from other sites.

β-Catenin Expression in Oropharyngeal Squamous Cell Carcinomas: Comparison and Correlation with p16 and Human Papillomavirus in situ Hybridization

BACKGROUND

The Wnt/β-catenin signaling pathway has been noted to be upregulated in head and neck cancers, including oropharyngeal squamous cell carcinoma (OSCC). This study compared the efficacy of β-catenin immunohistochemistry (IHC), p16 IHC and automated human papillomavirus (HPV) in situ hybridization (ISH) in OSCC.

METHODS

Sixty-eight OSCCs (48 surgical specimens and 20 fine-needle aspirations) were evaluated. Nuclear staining only of β-catenin was assessed as 0-3+ intensity (relative to controls of benign squamous mucosa). p16 was interpreted as positive if 70% of tumor cells showed brown nuclear and cytoplasmic staining. HPV ISH was interpreted as positive if a minimum of one tumor cell showed brown punctate dot-like nuclear positivity. p16 IHC and HPV ISH were then correlated with β-catenin staining. HPV ISH was used as the gold standard.

RESULTS

Twenty-five of 48 surgical specimens (52.1%) and 11 of 20 cell blocks (55%) stained positively for β-catenin, making a total of 36 of 68 (52.9%) staining positively for β-catenin, as compared to 61.7% positive for p16 IHC and 70.6% positive by automated HPV ISH, the gold standard method for OSCC diagnosis. x03C7;2 analysis revealed no significant correlation between β-catenin and HPV ISH (p > 0.05) and demonstrated a strong correlation between p16 and HPV ISH (p < 0.05).

CONCLUSION

β-Catenin IHC is not a sensitive or specific marker of HPV and is unlikely to be a useful adjunct to p16 IHC or HPV ISH in the setting of advanced OSCC. However, as this study focused on samples of advanced OSCC, β-catenin IHC may still find some use in the diagnosis of early-stage OSCC.

Pseudomyxoma peritonei: cytomorphologic findings and clinicopathologic correlates

INTRODUCTION

To analyze the cytomorphology and clinical correlates of pseudomyxoma peritonei (PP), a frequently fatal pathological entity defined by gelatinous ascites caused by slow but relentless accumulation of mucin produced by neoplastic glandular epithelium.

MATERIALS AND METHODS

A retrospective search of the electronic pathology data systems of three large tertiary care medical institutions revealed 41 cases from 32 patients with PP and corresponding abdominal fluid cytologic specimens. Cytologic material was available for review in 15 cases.

RESULTS

The primary tumor site was appendix in 25 (78.1%) of the 32 patients, other regions of the gastrointestinal tract in 2 (6.3%) patients, and in 5 (15.6%) patients, the primary could not be entirely identified. Of the 41 cases, only 15 had available cytologic slides to review. Extracellular mucin was a constant feature in all 15 (100%) cases, being abundant in 13 cases and focal in 2 cases. Predominance of mucin-secreting neoplastic epithelial cells were observed in 10 (66.7%) and muciphages in 11 (73.4%) cases. Cytopathologic interpretations were consistent with the subsequent histopathologic diagnosis in 30 of 32 cases (93.8%). There were two false negative cases, both of which showed scant mucinous material on second review.

CONCLUSIONS

PP is uncommonly encountered in routine cytopathology practice. The common denominator is the presence of an often-abundant extracellular mucin. Epithelial (glandular) component is usually scant. An accurate diagnosis in a fluid specimen requires proper identification of free/extracellular mucin as well as distinguishing the often "benign-appearing" epithelial cells from reactive mesothelial cells and histiocytes.

Accuracy of diagnosis of solid pseudopapillary tumor of the pancreas on fine needle aspiration: A multi-institution experience of ten cases

Introduction:

Solid pseudopapillary tumor of the pancreas (SPTP) is a neoplasm of uncertain origin and indolent biologic behavior with distinctive morphological features occurring predominantly in young women. This tumor has an excellent prognosis compared to neuroendocrine and acinar cell carcinoma, which are close differential diagnoses based on morphology, hence making it crucial to diagnose SPTP correctly.

Objectives:

To discuss the cytomorphological features of 10 cases of SPTP reported in two institutions and to evaluate the diagnostic accuracy of endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) cytology in establishing the diagnosis of SPTP.

Methods:

Ten diagnosed cases of SPTP were retrieved from the computerized endoscopy and pathology databases of our two tertiary care institutions. Nine patients had subsequent histological follow-up available. Eight patients underwent EUS-FNA while one patient each had ultrasound and computed tomography-guided FNA. The rapid on-site evaluation was carried out in all 10 cases, and additional material was retained for cell block preparation. Immunohistochemical (IHC) stains ranging from synaptophysin, progesterone receptor, chromogranin, β-catenin, CD10, and NSE were applied on cell blocks. Histological sections of all resected specimens were reviewed, and findings were correlated with those obtained by FNA.

Results:

Adequate material was obtained in all ten cases. IHC stains helped to confirm the cytological impression of SPTP. Histological examination of resection specimens, available in 9/10 cases, confirmed the cytological diagnosis.

Conclusions:

FNA particularly that obtained with EUS guidance is an effective tool in the accurate diagnosis of SPTP.

Expression of SOX10 in Salivary Gland Oncocytic Neoplasms: A Review and a Comparative Analysis with Other Immunohistochemical Markers

OBJECTIVES

We evaluated SOX10 (SRY-related HMG-box 10) in differentiating acinic cell carcinoma (AciCC) from other salivary gland neoplasms with oncocytic features on fine-needle aspiration cell blocks (FNA CB) and compared its performance to DOG1 (discovered on gastrointestinal stromal tumor 1).

MATERIAL AND METHODS

35 FNA CB of oncocytic salivary gland neoplasms, i.e. 13 cases of AciCC, 16 of Warthin tumor (WT), 3 of mucoepidermoid carcinoma (MEC) and 3 of oncocytoma (ONC), and 75 salivary gland resections, i.e. 26 AciCC, 7 WT, 36 MEC, 3 ONC, 2 mammary analog secretory carcinomas (MASC) and 1 papillary cystadenoma were stained for SOX10 and DOG1.

RESULTS

None of the benign oncocytic neoplasms were immunoreactive for SOX10 on CB or resection, similar to DOG1. On CB, 61.5 and 77% of AciCC were positive for SOX10 and DOG1, respectively. All surgically resected AciCC cases were positive for SOX10 and DOG1; other malignant oncocytic lesions such as MEC and MASC demonstrated variable SOX10 and DOG1 staining.

CONCLUSION

The use of SOX10 may increase the diagnostic accuracy of oncocytic lesions on FNA. In this context, SOX10 is equivalent to DOG1 in ruling out benign lesions such as WT and ONC; however, negative results for SOX10 as well as DOG1 do not favor a benign diagnosis since MEC is often negative for both markers.