Comparative evaluation of pan‐fungal real‐time PCR,galactomannan and (1‐3)‐β‐D‐glucan assay for invasive fungal infection in paediatric cancer patients

Limited specific data and investigations are available for the diagnosis of Invasive Fungal Infection (IFI) in paediatrics cancer patients. Three non‐invasive tests; Platelia Aspergillus EIA for galactomannan (GM), β‐D‐glucan (BDG) assay and pan‐fungal real‐time PCR for fungal DNA in blood were evaluated. One hundred twenty‐five paediatrics cancer patients at the high risk of IFI were enrolled. Single blood and serum samples were evaluated by all the three methods. Patients were classified into 10 proven, 52 probable and 63 no IFI cases in accordance with EORTC MSG 2008 revised guidelines. The sensitivity, specificity, PPV and NPV of all the three tests in proven, probable and no IFIs cases were analysed singly and in combination. The sensitivity, specificity, PPV and NPV of GM, BDG and pan‐fungal real‐time PCR were: 87%, 61%, 81%, 69.5% for GM, 88%, 59.5%, 81%, 71.4% for BDG and 89%, 69.2%, 85%, 67.5% for PCR (95% CI). Among different combinations, best combination was found to be GM and PCR with sensitivity, specificity, PPV and NPV of 98.2%, 89.3%, 97.1% and 90% respectively. Single samples must be evaluated by combination of tests.     

Prospective evaluation of a combination of fungal biomarkers for the diagnosis of invasive fungal disease in high‐risk haematology patients

We prospectively evaluated a combination of fungal biomarkers in adult haematology patients with focus on their clinical utility at different time points during the course of infection. In total, 135 patients were monitored once to twice weekly for serum (1‐3)‐ß‐d ‐glucan (BG), galactomannan (GM), bis‐methyl‐gliotoxin and urinary d ‐arabinitol/l ‐arabinitol ratio. In all, 13 cases with proven or probable invasive fungal disease (IFD) were identified. The sensitivity of BG and GM at the time of diagnosis (TOD) was low, but within 2 weeks from the TOD the sensitivity of BG was 92%. BG >800 pg/mL was highly specific for IFD. At a pre‐test probability of 12%, both BG and GM had negative predictive values (NPV) >0.9 but low positive predictive values (PPV). In a subgroup analysis of patients with clinically suspected IFD (pre‐test probability of 35%), the NPV was lower, but the PPV for BG was 0.86 at cut‐off 160 pg/mL. Among IFD patients, 91% had patterns of consecutively positive and increasing BG levels. Bis‐methyl‐gliotoxin was undetectable in 15 patients with proven, probable and possible IA. To conclude, BG was the superior fungal marker for IFD diagnosis. Quantification above the limit of detection and graphical evaluation of the pattern of dynamics are warranted in the interpretation of BG results.     

Testing the performance of a prototype lateral flow device using bronchoalveolar lavage fluid for the diagnosis of invasive pulmonary aspergillosis in high‐risk patients

The diagnosis of invasive pulmonary aspergillosis (IPA) increasingly relies on non‐culture‐based biomarkers in bronchoalveolar lavage (BAL) fluid. The Aspergillus lateral flow device (LFD) is a rapid immunoassay that uses a novel Aspergillus monoclonal antibody to gain specificity. The objective of the study is to compare specificity and sensitivity of the prototype LFD and the galactomannan (GM) enzyme immunoassay in BAL fluid in high‐risk patients. A total of 114 BAL samples from 106 patients at high risk for IPA were studied: 8 patients had proven/probable IPA, 16 had possible IPA and 82 did not have IPA. In patients with proven/probable IPA, specificity of LFD was 94% and GM was 89%; sensitivity of LFD was 38% and GM was 75%. Negative predictive value (NPV) for LFD was 94% and for GM was 98%; positive predictive value (PPV) was 38% for both tests. The use of anti‐mould prophylaxis did not affect specificity but resulted in decreased NPV of both LFD and GM. Union and intersection analysis showed no improvement in the performance by using both tests. Among patients at risk for IPA, the diagnostic performance of LFD and GM in BAL fluid appears comparable; specificity is high, but sensitivity of both LFD and GM is poor.     

Performance of lateral flow device and galactomannan for the detection of Aspergillus species in bronchoalveolar fluid of patients at risk for invasive pulmonary aspergillosis

Early diagnosis of invasive pulmonary aspergillosis (IPA) remains difficult due to the variable performance of the tests used. We compared the performance characteristics of Aspergillus lateral flow device (LFD) in bronchoalveolar lavage (BAL) vs. BAL‐galactomannan (GM), for the diagnosis of IPA. 311 BAL specimens were prospectively collected from patients who underwent bronchoscopy from January to May 2013. Patients at risk for IPA were divided into haematological malignancy (HEM) and non‐HEM groups: solid organ transplants (SOT) (lung transplant (LT) and non‐LT SOT); chronic steroid use (CSU); solid tumour (STU) and others. We identified 96 patients at risk for IPA; 89 patients (93%) were in the non‐HEM groups: SOT 57 (LT, 46, non‐LT SOT, 11); CSU 21; STU 6, other 5. Only three patients met criteria for IA (two probable; one possible). Overall sensitivity (SS) was 66% for both and specificity (SP) was 94% vs. 52% for LFD and GM respectively. LFD and GM performance was similar in the HEM group (SS 100% for both and SP 83% vs. 100% respectively). LFD performance was better than GM among non‐HEM SOT patients (P = 0.02). Most false‐positive GM results occurred in the SOT group (50.8%), especially among LT patients (56.5%). LFD performance was superior with an overall SP of 95.6% in SOT (P < 0.002) and 97% in LT patients (P = 0.0008). LFD is a rapid and simple test that can be performed on BAL to rule out IPA.     

Performance of serum (1,3)‐ß‐d‐glucan screening for the diagnosis of invasive aspergillosis in neutropenic patients with haematological malignancies

We report our experience with the use of (1,3)‐ß‐d ‐glucan (BDG) screening for the diagnosis of invasive aspergillosis (IA) in neutropenic patients with haematological malignancies. The performance of BDG screening was assessed retrospectively in per patient and per sample analyses. Overall, 20 among 167 patients developed IA (12%). In the per patient analysis, BDG showed 60% sensitivity and 78% specificity when the criterion for positivity was the presence of at least one BDG value ≥80 pg/mL. For 2 consecutive positive results, sensitivity decreased to 40%, while specificity increased to 93% and was similar to that of a positive galactomannan (GM; 90%). The highest specificity (97%) was observed for combined positivity of at least one BDG and at least one GM. In the per sample analysis, the specificity of BDG was 100% in the best scenario, 96% in the median scenario and 89% in the worst scenario. BDG became positive before GM in 33% of IA patients with both markers positive (n = 12). Despite good specificity for 2 consecutive positive results, the BDG test offered unsatisfactory performance for the diagnosis of IA due to low sensitivity. The combination of BDG and GM showed the potential for increasing specificity.     

Prevalence of the reversed halo sign in neutropenic patients compared with non‐neutropenic patients: Data from a single‐centre study involving 27 patients with pulmonary mucormycosis (2003‐2016)

Pulmonary mucormycosis (PM) is a life‐threatening infection and the diagnosis can be challenging. The objective was to retrospectively explore the value of the RHS in our cohort of 27 patients with mucormycosis and its relation to neutropenia. This was a retrospective study including all patients with a diagnosis of probable or proven invasive PM according to the 2008 EORTC/MSG criteria between September 2003 to April 2016. Fisher's exact test and Mann‐Whitney test, with a P‐value statistically significant under .05 (P<.05), were used to compare neutropenic and non‐neutropenic groups. 27 patients were eligible. The RHS could be identified in 78% of cases in the neutropenic group, and was less common in the non‐neutropenic group (31%) (P<.05). Reticulations inside ground‐glass opacity in case of RHS were present in 13 out of 15 patients (87%). Mucorales DNA detection by PCR on serum provided, a median time to the first PCR‐positive sample of 3 days (?33 to +60 days) before diagnosis was confirmed. Six patients had IPA co‐infection. In conclusion, RHS is more frequent in case of PM in neutropenic patients compare to non‐neutropenic patients. Its presence in immunocompromised patients should be sufficient to promptly start Mucorales‐active antifungal treatment, while its absence especially in non‐neutropenic cases should not be sufficient to exclude the diagnosis.     

Early serum (1→3)‐β‐D‐glucan levels in patients with burn injury

Serum (1→3)‐β‐D‐glucan (BG) is increasingly used as diagnostic marker for invasive fungal infections. Exposure to gauze may lead to false‐positive BG assays. The role of BG is unclear in thermally injured patients who frequently require extensive gauze coverage; therefore, we prospectively evaluated BG levels in burn‐injured patients. Serum BG levels were measured in 18 burn patients immediately before application of the first dressing and 12 h after. Patients were stratified by extent of total body surface area (TBSA) requiring gauze coverage: <20%, 20–39%, 40–60% and >60%. BG levels were obtained from patients with non‐burn trauma as controls. BG results were positive (>80 pg ml^?1) in 9/18 (50%) patients at baseline and in 8/18 (44%) 12 h after application of the first dressing. BG levels were positive in 1/5 (20%) of patients with <20% TBSA requiring gauze and in 10/13 (77%) with ≥20% (P < 0.05). None of the control patients had positive BG at any time point and none of the patients had candidemia at baseline. Mean serum BG levels decreased (19.44 pg ml^?1) after gauze placement. False‐positive serum BG elevations are common in this patient population. Positivity correlates with extent of TBSA injured, but is not impacted by the gauze itself.     

Immunological evaluation of peptide vaccination for cancer patients with the HLA ‐A11+ or ‐A33+ allele

The HLA‐A11 or ‐A33 allele is found in approximately 18% or 10% of the Asian population, respectively, but each of which is a minor allele worldwide, and therefore no clinical trials were previously conducted. To develop a therapeutic peptide vaccine for each of them, we investigated immunological responses of advanced cancer patients with the HLA‐A11⁺/A11⁺ (n = 18) or ‐A33⁺/A33⁺ (n = 13) allele to personalized peptide vaccine (PPV) regimens. The primary sites of HLA‐A11+/A11+ or ‐A33+/A33+ patients were the colon (n = 4 or 2), stomach (2 or 3), breast (3 or 2), lung and pancreas (2 or 2), and so on. For PPV, a maximum of four peptides were selected from nine different peptides capable of binding to HLA‐A11 and ‐A33 molecules based on the pre‐existing peptide‐specific IgG responses. There were no severe adverse events related to PPV. At the end of the first cycle, peptide‐specific CTL responses were augmented in 4/12 or 2/9 of HLA‐A11⁺/A11⁺ or ‐A33⁺/A33⁺ patients, while peptide‐specific IgG responses were augmented in 6/14 or 4/10 patients, respectively. Clinical responses consisted of four stable diseases and 14 progressive diseases in HLA‐A11⁺/A11⁺patients, versus seven and six in ‐A33⁺/A33⁺patients, respectively. Further clinical study of PPV could be recommended because of the safety and positive immunological responses.     

Diagnosis of invasive fungal infections using real-time PCR assay in paediatric acute leukaemia induction

Invasive fungal infections (IFI) lead to morbidity and mortality in neutropenic patients and in allogenic stem cell transplantation. Serum-based fungal detection assays have limitation of specificity or sensitivity. Studies on fungal DNA detection using real-time PCR in childhood leukaemia are lacking. The aim of this study was to develop sensitive and specific diagnostic tools for IFI in paediatric acute leukaemia patients using real-time PCR. Of 100 randomised paediatric acute leukaemia patients receiving antifungal prophylaxis with voriconazole/amphotericin B, single peripheral whole blood sample in EDTA was used for Pan-AC real-time PCR assay (detects nine Candida and six Aspergillus species) in patients who failed prophylaxis due to proven, probable, possible or suspected fungal infections. PCR results were retrospectively correlated with clinical profile. Real-time PCR test was positive in 18/29 (62%) patients who failed prophylaxis. The only patient with proven IFI (mucormycosis), real-time PCR assay was negative. Real-time PCR was positive in 2/4 (50%) patients with possible and 16/24 (66.6%) suspected IFI and 5/10 (50%) patients with pneumonia. By applying method A/B, sensitivity and positive predictive value could not be commented due to unproven Aspergillus or Candida infections; specificity and negative predictive values (NPV) were 41% and 100% respectively; by method C (included episodes of possible IFI as true positive), sensitivity, specificity, PPV and NPV were 50%, 36%, 11% and 81% respectively. In those with suspected IFI, 8/24 (33.3%) were PCR negative and unnecessarily received empirical antifungal therapy (EAFT). Real-time PCR is a practical, rapid, non-invasive screening test for excluding IFI in paediatric leukaemia. The high NPV makes real-time PCR a promising tool to use this prior to initiating EAFT in antibiotic-resistant febrile neutropenic patients; this would avoid toxicity, cost and hospitalisation for EAFT (ClinicalTrials.gov identifier:NCT00624143).     

Multicohort Retrospective Validation of a Predictive Biomarker for Topoisomerase I Inhibitors

PurposeThe camptothecin (CPT) analogs topotecan and irinotecan specifically target topoisomerase I (topoI) and are used to treat colorectal, gastric, and pancreatic cancer. Response rate for this class of drug varies from 10% to 30%, and there is no predictive biomarker for patient stratification by response. On the basis of our understanding of CPT drug resistance mechanisms, we developed an immunohistochemistry-based predictive test, P-topoI-Dx, to stratify the patient population into those who did and did not experience a response.Patients and MethodsThe retrospective validation studies included a training set (n = 79) and a validation cohort (n = 27) of gastric cancer (GC) patients, and 8 cohorts of colorectal cancer (CRC) patient tissue (n = 176). Progression-free survival for 6 months was considered a positive response to CPT-based therapy. Formalin-fixed, paraffin-embedded slides were immunohistochemically stained with anti–phospho-specific topoI-Serine10 (topoI-pS10), quantitated, and analyzed statistically.ResultsWe determined a threshold of 35% positive staining to offer optimal test characteristics in GC. The GC (n = 79) training set demonstrated 76.6% (95% confidence interval, 64-86) sensitivity; 68.8% (41-88) specificity; positive predictive value (PPV) 92.5% (81-98); and negative predictive value (NPV) 42.3% (24-62). The GC validation set (n = 27) demonstrated 82.4% (56-95) sensitivity and 70.0% (35-92) specificity. Estimated PPV and NPV were 82.4% (56-95) and 70.0% (35-92) respectively. In the CRC validation set (n = 176), the 40% threshold demonstrated 87.5% (78-94) sensitivity; 70.0% (59-79) specificity; PPV 70.7% (61-79); and NPV 87.0 % (77-93).ConclusionThe analysis of retrospective data from patients (n = 282) provides clinical validity to our P-topoI-Dx immunohistochemical test to identify patients with disease that is most likely to respond to topoI inhibitors.     

The clinical value of HPV genotyping in triage of women with high‐risk‐HPV‐positive self‐samples

Cytology alone, or combined with HPV16/18 genotyping, might be an acceptable method for triage in hrHPV‐cervical cancer screening. Previously studied HPV‐genotype based triage algorithms are based on cytology performed without knowledge of hrHPV status. The aim of this study was to explore the value of hrHPV genotyping combined with cytology as triage tool for hrHPV‐positive women. 520 hrHPV‐positive women were included from a randomised controlled self‐sampling trial on screening non‐attendees (PROHTECT‐3B). Eighteen baseline triage strategies were evaluated for cytology and hrHPV genotyping (Roche Cobas 4800) on physician‐sampled triage material. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), referral rate, and number of referrals needed to diagnose (NRND) were calculated for CIN2+ and CIN3+. A triage strategy was considered acceptable if the NPV for CIN3+ was ≥98%, combined with maintenance or improvement of sensitivity and an increase in specificity in reference to the comparator, being cytology with a threshold of atypical cells of undetermined significance (ASC‐US). Three triage strategies met the criteria: HPV16+ and/or ≥LSIL; HPV16+ and/or ≥HSIL; (HPV16+ and/or HPV18+) and/or ≥HSIL. Combining HPV16+ and/or ≥HSIL yielded the highest specificity (74.9%, 95% CI 70.5–78.9), with a sensitivity (94.4%, 95% CI 89.0–97.7) similar to the comparator (93.5%, 95% CI 87.7–97.1), and a decrease in referral rate from 52.2% to 39.5%. In case of prior knowledge of hrHPV presence, triage by cytology testing can be improved by adjusting its threshold, and combining it with HPV16/18 genotyping. These strategies improve the referral rate and specificity for detecting CIN3+ lesions, while maintaining adequate sensitivity.     

Utility of galactomannan antigen detection in bronchoalveolar lavage fluid in immunocompromised patients

Diagnosis of invasive pulmonary aspergillosis (IPA) is a challenging process in immunocompromised patients. Galactomannan (GM) antigen detection in bronchoalveolar lavage (BAL) fluid is a method to detect IPA with improved sensitivity over conventional studies. We sought to determine the diagnostic yield of BAL GM assay in a diverse population of immunocompromised patients. A retrospective review of 150 fiberoptic bronchoscopy (FOB) with BAL for newly diagnosed pulmonary infiltrate in immunocompromised patients was performed. Patient information, procedural details and laboratory studies were collected. BAL and serum samples were evaluated for GM using enzyme‐linked immunoassay. Of 150 separate FOB with BAL, BAL GM was obtained in 143 samples. There were 31 positive BAL GM assays. In those 31 positive tests, 13 were confirmed as IPA, giving a positive predictive value of 41.9%. There was one false negative BAL GM. Of the 18 false positive BAL GM, 4 were receiving piperacillin–tazobactam and 11 were receiving an alternative beta‐lactam antibiotic. BAL GM assay shows excellent sensitivity for diagnosing IPA. There was a significant number of false positive BAL GM assays and several of those patients were receiving beta‐lactam antibiotics at the time of bronchoscopy.     

Reactivity of the 1,3‐β‐D‐glucan assay during bacteraemia: limited evidence from a prospective study

There are discrepancies in the retrospective studies published in literature of whether or not bacteraemia could lead to false positivity of 1,3‐β‐D (BG) glucan assay. We performed, for the first time, a prospective study evaluating the role of bacterial bloodstream infection to the reactivity of BG assay. Twenty‐six episodes of bacteraemia that occurred in high‐risk haematological patients were included in our study. Consecutive BG levels >80 pg ml^?1 were required for test positivity. Only 2 of 26 patients were BG positive – both with IFDs. Thus, we prospectively did not prove bacteraemia as the source of cross reactivity of BG assay in haematological patients.     

Assessment of the lightcycler PCR assay for diagnosis of invasive aspergillosis in paediatric patients with onco-haematological diseases

A reliable diagnosis of invasive aspergillosis (IA) is hampered by the difficulty in obtaining suitable tissue samples. To evaluate the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the LightCycler PCR for the diagnosis of IA, 536 blood samples were collected over a 22-month period from 62 paediatric patients (median age 10 years, range 1-18) considered at risk of IA. The galactomannan antigen (GM) and fungal DNA were assessed on serial blood samples. IA was diagnosed in eight of 62 patients (13%): proven, five, probable, three. Sensitivity, specificity, PPV and NPV of LightCycler PCR varied according to the number of positive samples used to define positivity: 88%; 37%; 17% and 95% for single sample positivity; and 63%, 81%, 33% and 94% for serial sample positivity respectively. The concordance between positivity of LightCycler PCR assay and the diagnosis of IA was 79%. The single positivity of LightCycler PCR assay showed a good sensitivity for the diagnosis of IA in paediatric patients. The high NPV makes LightCycler PCR a promising tool in addition to GM testing to design a strategy of pre-emptive antifungal therapy, although further validation studies are needed.     

Performance of 1,3‐beta‐D‐glucan in the diagnosis and monitoring of invasive fusariosis

Invasive fusariosis (IF) usually presents with high fungal burden at diagnosis, and this may contribute to its high mortality rate. The use 1,3‐beta‐D‐glucan (BDG) may help to establish the diagnosis at an earlier disease stage and to monitor treatment. To evaluate the performance of BDG in the diagnosis of IF and its kinetics in relation to the outcome, we retrospectively tested serum samples of 13 cases of IF, analysed the temporal relationship between the first positive BDG test and the date of the diagnosis of IF, and the kinetics of BDG in relation to patients’ outcome. We selected 13 controls with similar underlying diseases as cases, at least two serum samples stored, and no invasive fungal disease. Twelve patients with IF had at least one positive BDG (median 4, range 1‐16). The test was positive before the diagnosis of IF in 11 of the 12 patients (91.6%), at a median of 10 days (range 1‐32). The median BDG value increased (from 109 to 316 pg/mL, P = 0.04) in patients who died by day 30, and did not change significantly (99‐101 pg/mL, P = 0.60) in survivors. Using two consecutive BDG tests, sensitivity, specificity, and positive and negative predictive values were 85%, 69%, 7% and 99%, respectively. BDG is positive in the majority of patients with IF, usually before the diagnosis, but the low positive predictive value limits its use to diagnose IF earlier. Once therapy is started, decreasing BDG values suggests treatment response.     

Diagnostic accuracy of the Aspergillus‐specific bronchoalveolar lavage lateral‐flow assay in haematological malignancy patients

We evaluated the performance of the Aspergillus‐specific lateral‐flow device (LFD) test for diagnosing invasive pulmonary aspergillosis (IPA) in patients with underlying haematological malignancies. Participating centres were the two Austrian University Hospitals of Graz and Innsbruck. LFD performance was evaluated with 95 bronchoalveolar lavage fluid (BALF) samples from 72 patients collected prospectively in Graz, and with 24 BALF bio bank samples from 23 patients (21 samples with probable IPA) in Innsbruck. Invasive fungal infections were classified according to the revised European Organization of Research and Treatment of Cancer/Mycoses Study Group criteria. Overall, 27 patients (30 samples) had probable IPA, 32 (43 samples) possible and 36 (46 samples) did not fulfil IPA criteria. The vast majority of patients – in particular those with probable IPA – received mould‐active treatment before bronchoscopy. Sensitivity, specificity, positive predictive value and negative‐predictive‐value for probable IPA diagnosis using the BALF‐LFD test were 71%, 76%, 35% and 94% for the Graz cohort. Sensitivity of the BALF‐LFD test for probable IPA was 57% in Innsbruck bio bank samples. Our results indicate that the BALF‐LFD‐test provides fast results with moderate sensitivities in patients with underlying haematological malignancies. Similar to other diagnostic tests and biomarkers sensitivity of the test may be influenced by ongoing systemic mould‐active treatment.     

Role of 18F‐FDG‐PET/CT in the management of marginal zone B cell lymphoma

The use of PET in patients with marginal zone B cell lymphoma (MZL) is controversial because of variability of fluorodeoxyglucose (FDG) avidity. We analyzed 40 PET/CT in 25 consecutive patients to compare its performance with CT at staging and as a first‐line response assessment. Sensitivity of PET/CT and CT was 96 and 76%. Mean standard uptake value was 6.1, 6.9 and 3.4 (p = 0.3) in nodal, extranodal and splenic subtypes, respectively. Of 17 patients (extranodal: n = 9; nodal: n = 6; splenic subtype: n = 2) with both imaging tests available at diagnosis, 8 (47%) had more involved areas with PET/CT than with CT, 75% of which were extranodal lesions. PET/CT resulted in upstaging of five patients although treatment of only two of them was changed. Responses of 15 patients with post‐treatment PET/CT were the following: 9 negative and 6 positive of which 3 were isolated residual lesions. Progression was documented in two of these three patients. Response was also assessed by CT in 11 patients. Discrepancies were found in three: Two were in complete remission by CT while PET/CT detected localized residual disease; another patient was in partial remission by CT, whereas PET/CT showed only one positive lesion. Two of these three patients relapsed. Patients with negative post‐treatment PET/CT did not relapse. With a median follow‐up of 50 months (10–152 months), 3‐year overall survival was 100 and 80% for patients with negative and positive post‐treatment PET/CT (p = 0.2). Three‐year disease‐free survival was 86%; the negative predictive value (NPV) was 100%, and the positive predictive value (PPV) was 83.3%. Although a larger number of patients will be required to further confirm these data, we can conclude that PET/CT is a useful imaging tool for both staging and response assessment in patients with nodal and extranodal MZL as a result of its high sensitivity, NPV and PPV. Copyright © 2014 John Wiley & Sons, Ltd.     

中间微丝蛋白和癌胚抗原在不同淋巴结肿瘤细胞中的选择性表达

 本文作者采用过氧化物酶标单克隆抗体免疫细胞化学技术, 对41例淋巴结肿瘤细针吸取细胞的中间微丝蛋白和癌胚抗原表达进行了研究。 结果表明, 不同组织起源的淋巴结肿瘤细具有各异的中间微丝蛋白和癌胚抗原表达, 转移癌细胞Keratin阳性, Vimentin存在于间叶起源的肿瘤细胞, 而癌胚抗原则是单层上皮组织起源肿瘤细胞的标志, 其选择性表达具有很高的敏感性和特异性, 在临床上有助于细胞学的监别诊断。     

Assessing the status of axillary sentinel lymph nodes of breast carcinoma patients by a real-time quantitative RT-PCR assay for mammaglobin 1 mRNA

Summary The aim of the study was to assess the accuracy of a real-time quantitative RT-PCR (qRT-PCR) assay for mammaglobin 1 mRNA in the detection of metastatic breast cancer in axillary sentinel lymph nodes (SLN), comparing the results with those of qualitative RT-PCR assays and of an extensive histopathological examination. A retrospective series of 81 SLN from 72 patients and a validation series of 61 SLN from 61 patients were evaluated. In the retrospective series, the qRT-PCR assay was positive for 23 (28.4%) of the 81 SLN. The overall concordance with histopathology was 93.8%, with a sensitivity of 90.9%, a specificity of 94.9%, a positive predictive value (PPV) of 87% and a negative predictive value (NPV) of 96.6%. In the same series, qualitative RT-PCR showed an overall concordance with histopathology of 86.4%, a sensitivity of 72.7%, a specificity of 91.5%, a PPV of 76.2% and a NPV of 90%. In the validation series, including 23 patients with pure in situ carcinoma, the real-time qRT-PCR assay showed an overall concordance with the histopathologic findings of 93.4%, with a sensitivity of 75.0%, a specificity of 94.7%, a PPV of 50.0% and a NPV of 98.2%. We conclude that real-time qRT-PCR assays for mammaglobin 1 are more sensitive and specific that qualitative RT-PCR assays for the detection of metastatic breast carcinoma in axillary SLN, but it should not be regarded as a possible substitute for an extensive histopathological scrutiny of the SLN in the clinical practice.     

Frequent false-positive results of Aspergillus latex agglutination test: transient Aspergillus antigenemia during neutropenia.

BACKGROUND: Two serologic assays, Aspergillus latex agglutination testing (LA) and plasma (1-->3)-beta-D-glucan (BDG) measurement, are used when invasive pulmonary aspergillosis (IPA) is suspected. Despite the high specificity of these assays, false-positive results are frequent for neutropenic patients. This study was conducted to evaluate the efficacy of LA and BDG and to investigate the cause of the false-positive results. METHODS: Eighty-eight consecutive patients with hematologic malignancies who underwent intensive chemotherapy were tested weekly with LA and BDG. RESULTS: Sixteen of 88 patients were diagnosed as having IPA. The sensitivity, specificity, and positive predictive values were 23%, 98%, and 64% for LA and 27%, 88%, and 52% for BDG, respectively. Of 11 patients who became positive for LA only during neutropenic periods, 2 patients developed IPA. In contrast, six of eight patients who became positive for LA during nonneutropenic periods developed IPA. Transient Aspergillus antigenemia was more frequently encountered during neutropenia (2.9%) than during nonneutropenic periods (0.2%). The plasma BDG concentration increased at the nadir of neutropenia in 36 of 45 patients who had no signs of IPA, and it exceeded the level of 20 pg/mL in 2 patients. CONCLUSIONS: Both BDG and LA have a low sensitivity and a high specificity for IPA. However, the false-positive rate of LA increases during neutropenic periods. Caution should be exercised in interpreting the results of these blood tests, especially when patients are neutropenic.