D. N. Rana

Urine cytopathology: challenges, pitfalls, and mimics.

Urine cytopathology is a useful and noninvasive tool in the diagnosis and follow‐up of urothelial neoplasia, which remains complementary to emerging molecular tests. These specimens may be challenging and there are numerous mimics and diagnostic pitfalls with which to contend. This review discusses these various entities and includes consideration of ancillary tests that may be useful in the diagnostic procedure. Diagn. Cytopathol. 2012.

Establishment of an endobronchial ultrasound-guided transbronchial fine needle aspiration service with rapid on-site evaluation: 2 years experience of a single UK centre.

Endobronchial ultrasound (EBUS)‐guided transbronchial fine needle aspiration (TBFNA) is now well established as a minimally invasive, effective investigation which can provide information on both diagnosis and stage of lung cancer and is also useful in the investigation of mediastinal lymphadenopathy of uncertain aetiology. The service can be provided with or without rapid on‐site evaluation (ROSE) for specimen triage and provisional diagnosis. We outline our experience from the first 2 years of providing an EBUS service with ROSE, highlighting the practicalities of service provision, pitfalls encountered and lessons learned.

An audit of liquid‐based cervical cytology screening samples (ThinPrep and SurePath) reported as glandular neoplasia

S. A. Thiryayi, J. Marshall and D. N. Rana
An audit of liquid‐based cervical cytology screening samples (ThinPrep and SurePath) reported as glandular neoplasia

Bland dyskaryosis: a new pitfall in liquid-based cytology.

Objective:  To describe our experience in recognizing an unusual presentation of severe dyskaryosis at two large cytology centres using ThinPrep liquid‐based cytology (LBC). LBC has been introduced in England following successful pilot studies. It is clear that LBC improves visualization and preservation of cells, and that sensitivity for high‐grade dyskaryosis is at least as good as for conventional cytology, and may be better. Several variants of high‐grade dyskaryosis have been described on conventional cytology, including small and pale cell dyskaryosis. These are also seen on LBC.

Differentiating between endocervical glandular neoplasia and high grade squamous intraepithelial lesions in endocervical crypts: cytological features in ThinPrep and SurePath cervical cytology samples.

A recent audit at our institution revealed a higher number of cases diagnosed as endocervical glandular neoplasia on ThinPrep (TP) cervical cytology samples (9 cases) as opposed to SurePath (SP) (1 case), which on histology showed only high‐grade cervical intraepithelial neoplasia (CIN) with endocervical crypt involvement (CI). We attempted to ascertain the reasons for this finding by reviewing the available slides of these cases, as well as slides of cases diagnosed as glandular neoplasia on cytology and histology; cases diagnosed as high‐grade squamous intraepithelial lesions (HSIL) on cytology which had CIN with CI on histology and cases with mixed glandular and squamous abnormalities diagnosed both cytologically and histologically. Single neoplastic glandular cells and short pseudostratified strips were more prevalent in SP than TP with the cell clusters in glandular neoplasia 3–4 cells thick, in contrast to the dense crowded centre of cell groups in HSIL with CI. The cells at the periphery of groups can be misleading. Cases with HSIL and glandular neoplasia have a combination of the features of each entity in isolation. The diagnosis of glandular neoplasia remains challenging and conversion from conventional to liquid based cervical cytology requires a period of learning and adaptation, which can be facilitated by local audit and review of the cytology slides in cases with a cytology–histology mismatch. Diagn. Cytopathol. 2009.

Fine needle aspiration cytology diagnosis of extramedullary haematopoiesis presenting as a pre-sacral mass: a pitfall avoided.

Dear Editor, Extramedullary haematopoiesis (EMH), or myeloid metaplasia, is the production of normal blood cells outwith the bone marrow and can produce a mass. Although physiological in foetal life, it is considered pathological after birth. EMH usually occurs in conjunction with haematological disorders, most commonly myelofibrosis, but rarely occurs without this association. EMH can be treated with radiotherapy or surgery, but often requires no specific treatment. It generally occurs in the liver and spleen but has been reported in diverse tissues and organs, including spinal tissues, lymph nodes and the mediastinum. We report a case of EMH presenting as a pre-sacral mass, a rarely reported site, and discuss the cytological diagnosis on fine needle aspiration (FNA). A 66-year-old woman presented with back pain 6 years after a total abdominal hysterectomy and bilateral salpingo-oophorectomy for a FIGO stage 1B endometrial adenocarcinoma. There was no clinical history of a haematological disorder. A magnetic resonance imaging scan detected an ill-defined 4.0cm diameter lesion in the pre-sacral region, which was suspicious for a liposarcoma. After clinical discussion, a 22G FNA sample was taken under computed tomography guidance. Direct spreads stained with May-Grünwald–Giemsa revealed a cellular aspirate containing immature blood cells, including megakaryocytes, myeloid cells and normoblasts, indicative of trilineage haematopoiesis (Figure 1). Lymphoid cells and plasma cells were also seen. Trilineage haematopoiesis was confirmed by haematoxylin and eosin staining and immunocytochemistry for megakaryocyte (factor VIII), myeloid (myeloperoxidase) and erythroid (glycophorin A) lineages, performed on an agar cell block (Figure 2a,b). The patient was subsequently managed conservatively based on this FNA diagnosis. A bone marrow trephine biopsy was subsequently performed, which was normal. EMH can be a straightforward cytological diagnosis that can be made even without the aid of immunocytochemistry, if it is considered in the differential diagnosis. However, we would like to emphasize the principal pitfall, which is a malignant cytology diagnosis based on the massive size and severe nuclear pleomorphism of normal megakaryocytes. We are aware of two previous reports of EMH, both of which involved a false-positive cytology diagnosis due to mistaking megakaryocytes for malignant cells. Malignant diagnoses, including pleomorphic sarcoma, anaplastic carcinoma and Hodgkin s lymphoma, might be considered if the megakaryocytes were focused on in isolation. Other possible differential diagnoses include granulocytic sarcoma, myelolipoma and inadvertent sampling of bone marrow. Granulocytic sarcoma FNA cytology is characterized by myeloid Correspondence: Dr P. K. Wright, Manchester Cytology Centre, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL, UK Tel.: 0161-276-5099; Fax: 0161-276-5098 E-mail: paulkwright1@gmail.com Figure 1. Direct spread of fine needle aspirate showing normoblasts (black arrow), myeloid precursors (green arrow) and megakaryocytes (red arrow) (May-Grünwald–Giemsa ·600).

Cytomorphological evaluation of a small round blue cell tumour of the head and neck.

Merkel cell carcinoma (MCC) is a rare neuroendocrine neoplasm of the skin which usually occurs in males over the age of 60. It is a highly aggressive and lethal tumour, comparable to small cell lung carcinoma and melanoma in its behaviour with regard to recurrence, metastatic spread and mortality. It is generally agreed that the primary tumour should be treated early and aggressively. Fine needle aspiration cytology (FNAC) enables an early and confident diagnosis of this aggressive tumour. We describe the cytological and immunocytochemical findings in a case of MCC diagnosed by FNAC, with subsequent histopathological confirmation.

Malakoplakia diagnosed by fine needle aspiration (FNA) and liquid‐based cytology (LBC) presenting as a pararenal mass in a transplant kidney

Dear Editor, Malakoplakia is an uncommon chronic inflammatory condition that has a gross and microscopic appearance resembling xanthogranulomatous pyelonephritis. It commonly affects the urinary tract, particularly in immunosuppressed patients, and has been reported in renal transplants, where the diagnosis is established by renal biopsy. To our knowledge, fine needle aspiration (FNA) cytology has not yet been reported in the diagnosis of malakoplakia in a renal transplant setting. We report a case of malakoplakia presenting as a pararenal mass in a transplant kidney, diagnosed by FNA cytology with the use of liquid-based cytology (LBC), enabling confirmatory histochemistry. A 64-year-old man with a history of renal transplant 3 years previously was receiving maintenance prednisolone and mycophenylate immunosuppression. During a routine clinic appointment, his creatinine levels were noted to have risen from 170 to 210 lmol/L over 2 months, although he felt well with no signs of infection. Virology investigations were negative. An ultrasound scan performed to look for hydronephrosis or renal artery stenosis detected a perivesical soft tissue mass lying adjacent to the grafted kidney (Figure 1). A computed tomography (CT) scan of the pelvis revealed the mass to be 4 cm in maximum diameter, close to the renal hilum and the urinary bladder wall, but separate from both structures and with no evidence of hydronephrosis. The clinical and radiological suspicion included malignancy or a lymphocoele from the transplant surgery. Ultrasound-guided FNA was performed with an air-dried May–Gr€ unwald–Giemsa (MGG)and alcohol-fixed Papanicolaou (Pap)-stained direct spread prepared from each of two aspirates. The needle from each pass was rinsed in CytoRich Red preservative fluid, which was used to prepare a SurePathTM (Source BioScience Healthcare, Nottingham, UK) slide on a PrepstainTM (TriPath Imaging, Burlington, NC, USA) slide processor using the non-gynaecological staining method. An agar cell block was subsequently prepared from the material remaining in the SurePath tube. Microscopic examination of the direct spread and LBC slides revealed numerous large histiocytes with abundant foamy cytoplasm, many of which contained calcified inclusions that exhibited a concentric, laminated and targetoid appearance (Figure 2a,b). These calcified bodies were also present extracellularly in the background and in cell block sections stained positively with periodic acid Schiff (PAS) and von Kossa stains (Figure 2c), but were negative with Perl’s stain. These morphological and histochemical characteristics were consistent with Michaelis–Gutmann bodies and the final diagnosis was malakoplakia, with no evidence of malignancy. A follow-up ultrasound 6 months later showed a reduction in the size of the mass consistent with its benign aetiology. No further FNA samples were taken. Michaelis and Gutmann described malakoplakia in 1902, using a term derived from the Greek words ‘malakos’, meaning soft, and ‘plakos’, meaning plaque, which describes the macroscopic appearance of the lesions. Malakoplakia is characterized cytologically by distinctive Michaelis–Gutmann bodies, which are pathognomonic for the condition and are derived from phagolysosomes containing incompletely destroyed bacteria. The age at diagnosis ranges from 6 to 85 years, with an average age of 50 years at presentation and a female to male ratio of 4 : 1. The proposed underlying defect is impaired macrophage bactericidal ability. Malakoplakia can affect any organ system, but genitourinary tract

Dual-colour multiplex staining for p40 and CK 5/6 in cytology samples for non-small cell lung cancer: a powerful combination for minimalist immunocytochemistry analysis

Dear Editor, In their recent review, Fassina et al. gave a comprehensive overview of the current status and future perspective of fine needle aspiration (FNA) cytology in non-small cell lung cancer. A recurrent theme that drives developments in this area is the need for accurate tumour subtyping to guide personalized therapy, which must be met in spite of often encountered biological (poorly differentiated tumours) and/or technical (poorly preserved or scanty samples) difficulties. In this context, immunocytochemistry is a key ancillary technique for tumour characterization. The article describes the widely used four-marker panel of Napsin A, TTF1, p63 and CK5/6, which are generally applied as single stains to help differentiate squamous cell carcinoma and adenocarcinoma. In this regard, we would like to highlight two additional techniques which, according to increasing evidence, can further aid progress on a tissue-sparing analytic pathway: the application of p40 immunostaining instead of p63, and the use of dual-colour multiplex staining. We also briefly describe our method of combining these two approaches, which we have successfully used in the analysis of a range of cytological sample types. p40 is a short isoform of p63 (DNp63). Detection of p40 by immunostaining has recently been shown to be equal in sensitivity but superior in specificity to p63 in the identification of squamous cell carcinoma. While p63 was found to be positive in 31% of adenocarcinomas and 54% of large cell lymphomas in one study of whole lung tissue sections, p40 staining was detected in 3% and 0%, respectively. These and similar results by others have led to the proposed use of p40 in place of p63 as a marker for squamous cell carcinoma. Another approach towards minimalist immunocytochemistry analysis is the use of dual-colour multiplex staining. Combinations of TTF1 and Napsin A, or p63 and CK5/6 have been successfully used on FNA and pleural fluid cytology specimens. By combining a nuclear and cytoplasmic stain on one slide, a more streamlined algorithm may be developed, leaving more material for further molecular analyses. We have successfully combined both of these approaches by developing a dual-colour multiplex staining protocol for p40 and CK 5/6 detection. Furthermore, in our initial assays on cytology specimens, we have found this staining combination, along with the Napsin A + TTF1 dual stain, to be useful in a range of sample types, including FNA, bronchial brushing and bronchial lavage samples. In brief, the sections of cell blocks for double staining

Outcomes of endoscopic ultrasound-guided pancreatic FNAC diagnosis for solid and cystic lesions at Manchester Royal Infirmary based upon the Papanicolaou Society of Cytopathology pancreaticobiliary terminology classification scheme

To compare endoscopic ultrasound (EUS)‐FNAC diagnosis of pancreatic lesions with patient outcome based upon the Papanicolaou Society of Cytopathology pancreaticobiliary terminology classification scheme diagnostic categories: Panc 1 (non‐diagnostic); Panc 2 (negative for malignancy/neoplasia); Panc 3 (atypical); Panc 4B (neoplastic, benign); Panc 4O (neoplastic, other); Panc 5 (suspicious of malignancy); and Panc 6 (positive/malignant).