Kinase expression in angiomatoid fibrous histiocytoma: panTRK is commonly expressed in the absence of NTRK rearrangement.

Angiomatoid fibrous histiocytoma (AFH) is a soft tissue tumour of intermediate (rarely metastasising) malignant potential, which harbours EWSR1/FUS gene fusions. These tumours can express anaplastic lymphoma kinase (ALK) in the absence of gene rearrangement or copy number alteration and can also coexpresses Pan-TRK immunohistochemistry (IHC). All EWSR1/FUS-rearranged AFH were retrieved from the files of three institutions and Pan-TRK (EPR17341), ALK and BRAF V600E IHC were performed. Fourteen AFH cases were identified, which included three cases of intracranial mesenchymal tumours with FET-CREB fusions. PanTRK and ALK positive immunostaining was identified in 9 (64.2%) and 12 (85.7%) cases, respectively. No NTRK or ALK translocations or increased copy number/amplification were identified in all eight cases which had fluorescence in situ hybridisation and/or next generation sequencing for NTRK1-3 and ALK available for assessment. None of the cases expressed BRAF-V600E.Although our study is limited, our report is the first to document PanTRK expression in AFH in the absence of identifiable NTRK1-3 gene alterations.

Improving sarcoma classification by using RNA hybridisation capture sequencing in sarcomas of uncertain histogenesis of young individuals.

Our aim was to utilise a 241-gene RNA hybridisation capture sequencing (CaptureSeq) gene panel to identify unexpected fusions in undifferentiated, unclassified or partly classified sarcomas of young individuals (<40 years). The purpose was to determine the utility and yield of a large, targeted fusion panel as a tool for classifying tumours that do not fit typical diagnostic entities at the time of the original diagnosis. RNA hybridisation capture sequencing was performed on 21 archival resection specimens. Successful sequencing was obtained in 12 of 21 samples (57%), two of which (16.6%) harboured translocations. A novel NEAT1::GLI1 fusion, not previously reported in the literature, presented in a young patient with a tumour in the retroperitoneum, which displayed low grade epithelioid cells. The second case, a localised lung metastasis in a young male, demonstrated a EWSR1::NFATC2 translocation. No targeted fusions were identified in the remaining 83.4% (n=10) of cases. Forty-three per cent of the samples failed sequencing as a result of RNA degradation. RNA-based sequencing is an important tool, which helps to redefine the classification of unclassified or partly classified sarcomas of young adults by identifying pathogenic gene fusions in up to 16.6% of the cases. Unfortunately, 43% of the samples underwent significant RNA degradation, falling below the sequencing threshold. As CaptureSeq is not yet available in routine pathology practice, increasing awareness of the yield, failure rate and possible aetiological factors for RNA degradation is fundamental to maximise laboratory procedures to improve RNA integrity, allowing the potential identification of significant gene alterations in solid tumours.

Inflammatory lobular hemangioma (T-cell-rich angiomatoid polypoid pseudolymphoma)-Assessment of FOS/FOSB and lymphoid markers and comparison with epithelioid hemangioma.

BACKGROUND: T-cell-rich angiomatoid polypoid pseudolymphoma (TRAPP) and inflammatory lobular hemangioma (ILH) encompass a spectrum of cutaneous vascular lesions in which a prominent lymphoplasmacytic component may impart a pattern highly reminiscent of low-grade cutaneous lymphoma (pseudolymphoma). Epithelioid hemangioma, including its most common variant angiolymphoid hyperplasia with eosinophilia (ALHE), is a distinct entity associated with FOS and/or FOSB expression detected by immunohistochemistry (IHC). These entities can show significant morphological overlap. METHODS: We performed IHC for FOSB, FOS, and lymphoid markers in a series of TRAPP/ILH and ALHE. RESULTS: We identified 13 cases of ILH/TRAPP, which showed a predominance in CD8+ T-cells (CD8>CD4: 11/13) while FOSB and FOS were expressed in 36% (4/11) and 27% (3/11) of cases, respectively. ALHE (n = 9) showed a predominance in CD4+ T-cell (67%) with FOSB and FOS co-expression in 78% (seven of nine) of the cases. CONCLUSION: We showed, based on FOS and/or FOSB immunohistochemical expression, that there is a possible link between ILH/TRAPP and epithelioid hemangioma/ALHE. The use of FOS and FOSB IHC in the routine diagnostic setting of cutaneous vascular lesions will help to redefine cases of ILH/TRAPP as a subset of these may represent inflammatory variants of epithelioid hemangioma.

Molecular and immunohistochemical characterisation of mesothelioma of the tunica vaginalis.

AIMS: Malignant mesothelioma (MM) of the tunica vaginalis (TV) is a rare and aggressive tumour, and the molecular features and staining profile with contemporary immunohistochemical (IHC) biomarkers are largely unexplored. We characterise the clinicopathological, molecular and IHC features of MM (n = 13) and mesothelial neoplasms of uncertain malignant potential (MUMP) (n = 4). METHODS AND RESULTS: Targeted next-generation sequencing was performed on seven MMs and two MUMPs. IHC was performed for methylthioadenosine phosphorylase (MTAP), BRCA1-associated protein 1 (BAP1) and SRY-box transcription factor 6 (SOX6). Thirteen adenomatoid tumours were also assessed with SOX6. MM were epithelioid (seven of 13) or biphasic (six of 13). In MM, NF2 (five of seven; 71%), CDKN2A (three of seven; 43%) and BAP1 (two of seven; 29%) were most frequently altered. Non-recurrent driver events were identified in PTCH1 and TSC1. In contrast, none of these alterations were identified in MUMPs; however, one MUMP harboured a TRAF7 missense mutation. By IHC, loss of MTAP (two of 12; 17%) and BAP1 (two of nine; 22%) was infrequent in MM, whereas both were retained in the MUMPs. SOX6 was positive in nine of 11 (82%) MMs and negative in all MUMPs and adenomatoid tumours. CONCLUSIONS: Testicular MM exhibit a similar mutational profile to those of the pleura/peritoneum; however, alterations in CDKN2A and BAP1 are less common. These findings suggest that although MTAP and BAP1 IHC are specific for MM, their sensitivity in testicular MMs appears lower. In addition, rare tumours may harbour targetable alterations in driver genes (PTCH1 and TSC1) that are unusual in MMs at other anatomical sites. SOX6 is sensitive for MM; accordingly, the presence of SOX6 expression argues against a benign neoplastic process.

Myeloid sarcoma and extramedullary hematopoiesis expand the spectrum of ERG-positive proliferations: an ancillary tool in the diagnosis.

ERG overexpression has been linked to acute myeloid leukemia/myeloid sarcoma (MS). The aim of our study was to identify the frequency of ERG immunohistochemical (IHC) expression in MS (n = 21), blastic plasmacytoid dendritic cell neoplasms (BPDCNs; n = 8), extramedullary hematopoiesis (EMH: n = 9), normal and pathological bone marrow trephine biopsies (BM-TBs, n = 18), and the marrow component of adrenal myelolipomas (n = 15). ERG-positive and ERG-negative immunostains were identified in 68.4% and 31.5% of patients with MS, respectively (2-3+, 20% to >90% of cells), while all BPDCNs were negative. ERG + MS cases were over-represented in those of myeloid differentiation when compared with those of pure monocytic/monoblastic differentiation, which were ERG-negative (P=<0.001). ERG was expressed in immature myeloid cells in 100% of cases of EMH, BM-TBs, and adrenal myelolipomas (n = 42), resulting in a sensitivity of 100% in this setting. Negative ERG immunostaining was also 100% sensitive in discriminating cells of erythroid lineage, mature lymphocytes, and reactive or neoplastic plasma cells. Variable IHC expression occurred in megakaryocytes and neutrophils. In summary, we confirmed a high frequency of ERG expression in MS and identified ubiquitous expression in non-neoplastic immature myeloid lineage cells. We believe that ERG can be of diagnostic utility to identify neoplastic and reactive myeloid infiltrates in peripheral tissues and possibly as an ancillary marker to exclude the diagnosis of BPDCNs when positive. However, ERG must be used in an antibody panel, as expression is not limited to myeloid cells.

Lessons learnt from MDM2 fluorescence in-situ hybridisation analysis of 439 mature lipomatous lesions with an emphasis on atypical lipomatous tumour/well-differentiated liposarcoma lacking cytological atypia.

AIMS: Amplification of the murine double minute-2 (MDM2) gene, which is usually detected with fluorescence in-situ hybridisation (FISH), is the key driving event for atypical lipomatous tumours (ALTs)/well-differentiated liposarcomas (WDLs). We sought to determine the concordance between the histopathological findings and MDM2 FISH in the diagnosis of ALT/WDL, and to identify the histological features of MDM2-amplified tumours lacking classic atypia. METHODS AND RESULTS: We performed a retrospective analysis of all mature lipomatous lesions subjected to MDM2 FISH analysis at our institution. MDM2 FISH analysis was performed on 439 mature lipomatous lesions: 364 (82.9%) were negative and 75 (17%) were positive. In 17 of 75 (22.6%) ALTs/WDLs, cytological atypia was not identified on initial histological assessment, thus favouring lipoma. On review, these cases shared common histological features, consisting of a very low number of relatively small stromal cells within the tumour lobules, with mildly coarse chromatin and oval nuclei, admixed with unremarkable adipocytes in a tumour background devoid of fibroconnective septa, areas of fibrosis, or blood vessels. These cells matched the cells in which FISH showed MDM2 amplification. In contrast, 13 cases (3.5%) regarded as suspicious for ALT/WDL on the basis of histology lacked MDM2 amplification and were reclassified following the FISH findings. CONCLUSIONS: We conclude that a subset of lipoma-like ALTs/WDLs are not associated with any of the features typically described in ALT/WDL. Our study also showed that tumours >100 mm are more likely to be ALT/WDL; however, a history of recurrence or concerning clinical/radiological features was not significantly associated with classification as ALT/WDL.

Chromosome 8 Polysomy Accounting for MYC Over-Expression in Angiosarcoma Arising as Somatic-Type Malignancy in Metastatic Teratoma. Case Report.

MYC over-expression by immunohistochemistry (IHC) is utilised in routine pathology practice as a surrogate marker for MYC amplification, which plays a key oncogenic role in post-irradiation and chronic lymphedema-associated angiosarcoma. We present the case of a 32-year old male, who presented with high-grade angiosarcoma arising in a background of metastatic testicular teratoma. IHC for MYC showed strong nuclear expression in the angiosarcoma cells prompting the consideration of post-irradiation-induced angiosarcoma but our patient did not undergo radiotherapy. Fluorescence in-situ hybridization (FISH) excluded MYC amplification and instead showed Chromosome 8 polysomy, which accounted for the strong MYC IHC expression present, not previously described in the context of germ cell tumours. The occurrence of MYC over-expression due to polysomy illustrates a novel clinical scenario (angiosarcoma arising as somatic malignancy) where strong MYC IHC expression can be found in the absence of underlying amplification or prior radiotherapy exposure.

Expression of the C-terminal region of the SSX protein is a useful diagnostic biomarker for spermatocytic tumour.

AIMS: Spermatocytic tumour (ST) is a rare testicular germ cell neoplasm with few confirmatory biomarkers that can be challenging to diagnose. Like normal spermatogonia, STs are known to express SSX proteins. Recently, a novel SSX antibody directed against a conserved C-terminal region of SSX1, SSX2 and SSX4 (SSX_CT) has emerged as a reliable biomarker for these SSX proteins and synovial sarcoma. However, SSX_CT immunostaining has not been demonstrated in ST. The aim of this study was to assess the diagnostic utility of SSX_CT immunohistochemistry in ST and other tumours in the differential diagnosis with ST. METHODS AND RESULTS: SSX_CT, OCT3/4 and c-KIT immunohistochemistry was performed on 15 STs, 38 seminomas, 13 embryonal carcinomas, 12 yolk sac tumours, six choriocarcinomas, four teratomas, seven Sertoli cell tumours, and six lymphomas. Staining was scored as negative, rare, focal, or diffuse. SSX_CT was positive in all (15/15) STs, and diffusely positive in 14 of 15 (93%). SSX_CT was positive in 22 of 38 (58%) seminomas; however, only two cases showed diffuse expression. SSX_CT was negative in all other tumours. OCT3/4 was negative in all STs, but positive in all seminomas and embryonal carcinomas. c-KIT was frequently positive in both STs (12/15; 80%) and seminomas (33/38; 87%). OCT3/4 and c-KIT were negative in all other tumours. CONCLUSIONS: SSX_CT is a valuable and highly sensitive biomarker that supports the diagnosis of ST. Diffuse expression of SSX-CT in STs is also highly specific for ST. Nevertheless, SSX_CT is best used in combination with OCT3/4 when ST is in the differential diagnosis.

Pharmaceutical care issues in lung cancer: can community pharmacists support patients receiving systemic anticancer therapy?

OBJECTIVES: Most patients receive systemic anticancer therapy (SACT) as day cases and toxicities, if they occur, are likely to appear first in primary care. Pharmaceutical care can be delivered by community pharmacists, but little is known about the epidemiology of SACT toxicities in the community and potential interventions to address these which raise the following questions: what are the typologies of SACT-associated toxicities experienced by community-based patients and what are the associated pharmaceutical care issues (PCIs)? The aim of this study was to identify toxicities and pharmaceutical care issues of patients prescribed SACT for lung cancer and understand the potential for community pharmacists to deliver aspects of cancer care including toxicity management. METHODS: Retrospective analysis of clinical records of patients prescribed oral and parenteral SACT in 2013-14, to describe patient characteristics; SACT toxicity; PCIs and episodes of unscheduled care. KEY FINDINGS: Twelve categories of toxicity and 13 categories of PCIs were identified from 50 patients. More PCIs were observed with oral SACT/oral-parenteral combinations than with parenteral regimens. The PCIs which could be managed by community pharmacists were mucositis; skin toxicity; gastrointestinal toxicity; reinforcing patient education and identification/prevention of drug interactions. CONCLUSIONS: Community pharmacists are ideally placed to provide pharmaceutical care to patients with lung cancer prescribed SACT. Cancer specialists in secondary care can signpost patients to community pharmacists for early management of low-grade SACT toxicity.

Monotypic Plasma Cell Proliferation of Uncertain Clinical Significance Mimicking Interstitial Cystitis: An Early Lesion of MALT Lymphoma?

We prospectively studied our institutional experience of bladder extranodal marginal zone (mucosa-associated lymphoid tissue [MALT]) lymphoma including bladder biopsies in which the possibility of MALT lymphoma was considered. We identified a subset of cases primary to the urinary bladder, presenting with prominent plasma cell infiltrates and symptoms mimicking bladder pain syndrome/interstitial cystitis. These proliferations were designated for this study as "monotypic plasma cell proliferation of uncertain clinical significance" (MPCP-US), as the features were insufficient for diagnosis of MALT lymphoma. We identified 33 patients, consisting of 22 cases of MPCP-US (6 of which were associated with amyloid deposition) and 11 cases of MALT lymphoma. MPCP-US was more prevalent in men (73%), a mass lesion was not identified at cystoscopy, and only 1 case had an accompanying urinary tract infection (4.5%). Histologically, MPCP-US presented as monotypic plasma cells arranged in a superficial band-like distribution in the lamina propria, predominantly kappa restricted (68%) and IgA+ or IgM+ (64% and 23%, respectively) and without a histologic mass of atypical B cells or plasma cells, not diagnostic for established MALT lymphoma or plasmacytoma. Secondary involvement of the bladder by other lymphoproliferative disorders was excluded and there was no evidence of progressive disease. MALT lymphomas are presented for comparison and our analysis demonstrated that MPCP-US represent a different clinicopathologic entity compared with classic MALT lymphoma. We present the first series of cases of MPCP-US. The recognition of this entity is fundamental to the development of management protocols to relieve intractable symptoms mimicking bladder pain syndrome/interstitial cystitis in these patients.

Genome wide methylation profiling of selected matched soft tissue sarcomas identifies methylation changes in metastatic and recurrent disease.

In this study we used the Illumina Infinium Methylation array to investigate in a cohort of matched archival human tissue samples (n = 32) from 14 individuals with soft tissue sarcomas if genome-wide methylation changes occur during metastatic and recurrent (Met/Rec) disease. A range of sarcoma types were selected for this study: leiomyosarcoma (LMS), myxofibrosarcoma (MFS), rhabdomyosarcoma (RMS) and synovial sarcoma (SS). We identified differential methylation in all Met/Rec matched samples, demonstrating that epigenomic differences develop during the clonal evolution of sarcomas. Differentially methylated regions and genes were detected, not been previously implicated in sarcoma progression, including at PTPRN2 and DAXX in LMS, WT1-AS and TNXB in SS, VENTX and NTRK3 in pleomorphic RMS and MEST and the C14MC / miR-379/miR-656 in MFS. Our overall findings indicate the presence of objective epigenetic differences across primary and Met/Rec human tissue samples not previously reported.

Chromosomal imbalances detected in NTRK-rearranged sarcomas by the use of comparative genomic hybridisation.

AIMS: NTRK-rearranged sarcomas are emerging as a distinct class of sarcomas of particular importance in the era of targeted therapy. The aim of this study was to use array comparative genomic hybridisation (aCGH) to explore the cytogenetic profile of six adult soft tissue sarcomas harbouring NTRK gene fusions. METHODS AND RESULTS: aCGH was performed on six adult soft tissue sarcomas with proven NTRK rearrangements [NTRK1, n = 1 (TPM3-NTRK1); NTRK2, n = 1 (MTMR2-NTRK2); NTRK3, n = 4 (two ETV6-NTRK3; two with unknown partners). The morphological patterns of these cases included inflammatory myofibroblastic tumour-like, fibrosarcoma/malignant peripheral nerve sheath tumour-like, and Ewing sarcoma-like. On the basis of the number of chromosomal copy number variations (CNVs), ranging from two to 15 per sample, NTRK-associated sarcomas could be subdivided into two groups: one with a relatively simple karyotype (n = 2; median of three genomic alterations), and those with a more complex karyotype (n = 4; median of 11 genomic imbalances). Recurrent chromosomal CNVs included gains at chromosomes 6p, 1q, 7 (whole chromosome), and 12p, and losses at chromosomes 10q, 13q, 19q, and 9p. CONCLUSIONS: NTRK-rearranged sarcomas constitute a heterogeneous group of tumours that can show a relatively simple or a complex karyotype. Although there were some, but inconsistent, associations between karyotype complexity and morphology, our study showed that a more complex karyotype in this group of tumours appeared to correlate with more aggressive clinical behaviour. Gains at chromosome 6p and 1q were the most common recurrent genomic alterations, being present in 67% of the samples (4/6), followed by gains at chromosome 7, which were present in 50% of the samples (3/6).

Prevalence of PD-L1 expression in matched recurrent and/or metastatic sarcoma samples and in a range of selected sarcomas subtypes.

We assessed the frequency of programmed death-ligand 1 (PD-L1) expression by immunohistochemistry (IHC) in a cohort of 522 sarcomas from 457 patients, incuding a subset of 46 patients with 63 matched samples from local recurrence or metastases with primary tumours and/or metachronous metastases. We also investigated the correlation of PD-L1 with the presence and degree of tumour-infiltrating lymphocytes (TILs) in a subset of cases. IHC was performed using the PD-L1 SP263 companion kit (VENTANA) on tissue microarrays from an archival cohort. Evaluation of PD-L1 and TILs was performed on full sections for a subset of 23 cases. Fisher's exact and Mann Whitney test were used to establish significance (P <0.05). PD-L1 positive expression (≥1%) was identified in 31% of undifferentiated pleomorphic sarcomas, 29% of angiosarcomas, 26% of rhabdomyosarcomas, 18% of myxofibrosarcomas, 11% of leiomyosarcomas and 10% of dedifferentiated liposarcomas. Negative expression was present in all atypical lipomatous tumous/well-differentiated lipoasarcomas, myxoid liposarcomas, synovial sarcomas, pleomorphic liposarcomas, and Ewing sarcomas. PD-L1 IHC was concordant in 81% (38 of 47) of matched/paired samples. PD-L1 IHC was discordant in 19% (9 of 47 matched/paired samples), displaying differences in the proportion of cells expressing PD-L1 amongst paired samples with the percentage of PD-L1-positive cells increasing in the metastatic/recurrent site compared to the primary in 6 of 9 cases (67%). Significant correlation between PD-L1 expression and the degree of TILs was exclusively identified in the general cohort of leiomyosarcomas, but not in other sarcoma subtypes or in metastatic/recurrent samples. We conclude that the prevalence of PD-L1 expression in selected sarcomas is variable and likely to be clone dependent. Importantly, we demonstrated that PD-L1 can objectively increase in a small proportion of metastases/recurrent sarcomas, offering the potential of treatment benefit to immune checkpoint inhibitors in this metastatic setting.

A Clinicopathologic and Molecular Analysis of Fumarate Hydratase-deficient Renal Cell Carcinoma in 32 Patients.

Fumarate hydratase-deficient renal cell carcinoma (FH-deficient RCC) is a rare and recently described entity associated with hereditary leiomyomatosis and RCC syndrome. FH-deficient RCC may show variable clinical and pathologic findings, but commonly presents with locally advanced and metastatic disease and carries a poor prognosis. We identified 32 patients with FH-deficient RCC, confirmed by FH immunohistochemistry (IHC) and/or FH mutation analysis, and performed a retrospective review of the clinical and pathologic features. Median age at presentation was 43 years (range, 18 to 69 y), and the M:F ratio was 2.2:1. Median tumor size was 6.5 cm (range, 2.5 to 28 cm), and 71% presented at stage ≥pT3a. After a median follow-up of 16 months (range, 1 to 118 mo) in 26 patients, 19% showed no evidence of disease, 31% were alive with disease, and 50% were dead of disease. The vast majority of cases showed multiple histologic growth patterns, with papillary (52%) being the most common predominant pattern, followed by solid (21%), cribriform/sieve-like (14%), sarcomatoid (3%), tubular (3%), cystic (3%), and low-grade oncocytic (3%). Viral inclusion-like macronucleoli with perinucleolar clearing were present in almost all cases (96%). All cases were evaluated using FH IHC, and 3 cases (9%) showed retained FH expression. Nineteen cases had germline or tumor mutation analysis confirming a FH mutation, with 79% (11/14) of cases showing mutations within coding regions and 21% (3/14) showing mutations within intronic splice-sites. By IHC, 97% (32/33) of cases were negative for CK7, 93% (27/29) were negative for p63, and 52% (15/29) were negative for GATA3. All cases stained were positive for PAX8 and showed retained succinate dehydrogenase B expression. Our overall findings show that FH-deficient RCC is considerably heterogenous in morphology and frequently behaves aggressively. Suspicion for this entity should be raised even in the absence of predominantly papillary architecture and characteristic nucleolar features. We have included cases with uncommonly seen features, including 4 cases with predominantly cribriform/sieve-like architecture as well as one case with pure low-grade oncocytic morphology (9 y of clinical follow-up without evidence of disease). Although FH IHC is a useful tool for identifying cases of FH-deficient RCC, not all cases of FH-deficient RCC show loss of FH staining, and FH mutation analysis should be considered for patients with suspicious clinical or pathologic features, even in cases with retained FH IHC expression.

Challenges in Pathologic Staging of Renal Cell Carcinoma: A Study of Interobserver Variability Among Urologic Pathologists.

Staging criteria for renal cell carcinoma differ from many other cancers, in that renal tumors are often spherical with subtle, finger-like extensions into veins, renal sinus, or perinephric tissue. We sought to study interobserver agreement in pathologic stage categories for challenging cases. An online survey was circulated to urologic pathologists interested in kidney tumors, yielding 89% response (31/35). Most questions included 1 to 4 images, focusing on: vascular and renal sinus invasion (n=24), perinephric invasion (n=9), and gross pathology/specimen handling (n=17). Responses were collapsed for analysis into positive and negative/equivocal for upstaging. Consensus was regarded as an agreement of 67% (2/3) of participants, which was reached in 20/33 (61%) evaluable scenarios regarding renal sinus, perinephric, or vein invasion, of which 13/33 (39%) had ≥80% consensus. Lack of agreement was especially encountered regarding small tumor protrusions into a possible vascular lumen, close to the tumor leading edge. For gross photographs, most were interpreted as suspicious but requiring histologic confirmation. Most participants (61%) rarely used special stains to evaluate vascular invasion, usually endothelial markers (81%). Most agreed that a spherical mass bulging well beyond the kidney parenchyma into the renal sinus (71%) or perinephric fat (90%) did not necessarily indicate invasion. Interobserver agreement in pathologic staging of renal cancer is relatively good among urologic pathologists interested in kidney tumors, even when selecting cases that test the earliest and borderline thresholds for extrarenal extension. Disagreements remain, however, particularly for tumors with small, finger-like protrusions, closely juxtaposed to the main mass.

Thirty-years of screening for cystic fibrosis in East Anglia.

BACKGROUND: Newborn screening for cystic fibrosis (CF) relies on the measurement of immunoreactive trypsinogen (IRT) originating from the pancreas. The Norfolk, Suffolk and Cambridgeshire screening programme initially exploited the persistent increase in IRT seen in CF (IRT-IRT protocol) and later changed to include mutation analysis as a second tier test (IRT-DNA-IRT protocol). RESULTS: During a 30 year period 582 966 babies have been screened by IRT-IRT and 147 764 by IRT-DNA-IRT (total 730730), resulting in 296 screen positive cases of CF and 29 false negatives (including 10 false negatives with meconium ileus). Ten missed CF cases were pancreatic insufficient, however all were diagnosed before their first birthday, suggesting that a false negative result did not forestall appropriate clinical investigation. The IRT-DNA-IRT protocol had a much improved positive predictive value (PPV) of 85.9% compared to 67.3% for IRT-IRT, excluding CF babies with meconium ileus. The PPVs increased to 82.2% and 98.2% respectively if only well, term babies were considered. The main factor to account for this improvement in PPV has probably been the incorporation of DNA analysis in the second tier testing. CONCLUSIONS: The diagnosis of screen-positive babies proved difficult in a minority of cases with the classification of some patients changing with evolving phenotype. Our results illustrate the importance of collecting outcome data over a long time period for accurate assessment of the screening programme. This study provides evidence that newborn screening for CF is a valid undertaking that detects 95% of unsuspected CF cases presenting before 3 years of age.

Epithelioid and spindle cell haemangioma of bone.

A case of epithelioid and spindle cell haemangioma of bone occurring in the proximal femur is presented. The tumour had typical microscopic features with a striking lobular pattern comprising spindled and epithelioid areas with admixed inflammatory cells. The case represents only the eighth reported example of this rare tumour, which appears to fit in the spectrum of epithelioid haemangioma. This is the first case to involve the proximal portion of a long bone. A review of the classification and features of similar vascular tumours of bone is presented.