Nintedanib in patients with progressive fibrosing interstitial lung diseases-subgroup analyses by interstitial lung disease diagnosis in the INBUILD trial: a randomised, double-blind, placebo-controlled, parallel-group trial

BACKGROUND

The INBUILD trial investigated the efficacy and safety of nintedanib versus placebo in patients with progressive fibrosing interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis (IPF). We aimed to establish the effects of nintedanib in subgroups based on ILD diagnosis.

METHODS

The INBUILD trial was a randomised, double-blind, placebo-controlled, parallel group trial done at 153 sites in 15 countries. Participants had an investigator-diagnosed fibrosing ILD other than IPF, with chest imaging features of fibrosis of more than 10% extent on high resolution CT (HRCT), forced vital capacity (FVC) of 45% or more predicted, and diffusing capacity of the lung for carbon monoxide (DLco) of at least 30% and less than 80% predicted. Participants fulfilled protocol-defined criteria for ILD progression in the 24 months before screening, despite management considered appropriate in clinical practice for the individual ILD. Participants were randomly assigned 1:1 by means of a pseudo-random number generator to receive nintedanib 150 mg twice daily or placebo for at least 52 weeks. Participants, investigators, and other personnel involved in the trial and analysis were masked to treatment assignment until after database lock. In this subgroup analysis, we assessed the rate of decline in FVC (mL/year) over 52 weeks in patients who received at least one dose of nintedanib or placebo in five prespecified subgroups based on the ILD diagnoses documented by the investigators: hypersensitivity pneumonitis, autoimmune ILDs, idiopathic non-specific interstitial pneumonia, unclassifiable idiopathic interstitial pneumonia, and other ILDs. The trial has been completed and is registered with ClinicalTrials.gov, number NCT02999178.

FINDINGS

Participants were recruited between Feb 23, 2017, and April 27, 2018. Of 663 participants who received at least one dose of nintedanib or placebo, 173 (26%) had chronic hypersensitivity pneumonitis, 170 (26%) an autoimmune ILD, 125 (19%) idiopathic non-specific interstitial pneumonia, 114 (17%) unclassifiable idiopathic interstitial pneumonia, and 81 (12%) other ILDs. The effect of nintedanib versus placebo on reducing the rate of FVC decline (mL/year) was consistent across the five subgroups by ILD diagnosis in the overall population (hypersensitivity pneumonitis 73·1 [95% CI -8·6 to 154·8]; autoimmune ILDs 104·0 [21·1 to 186·9]; idiopathic non-specific interstitial pneumonia 141·6 [46·0 to 237·2]; unclassifiable idiopathic interstitial pneumonia 68·3 [-31·4 to 168·1]; and other ILDs 197·1 [77·6 to 316·7]; p=0·41 for treatment by subgroup by time interaction). Adverse events reported in the subgroups were consistent with those reported in the overall population.

INTERPRETATION

The INBUILD trial was not designed or powered to provide evidence for a benefit of nintedanib in specific diagnostic subgroups. However, its results suggest that nintedanib reduces the rate of ILD progression, as measured by FVC decline, in patients who have a chronic fibrosing ILD and progressive phenotype, irrespective of the underlying ILD diagnosis.

FUNDING

Boehringer Ingelheim.

Abstract PD1-06: Comparison of mutational landscapes of primary breast cancer and first metastatic relapse: Results from the ESOPE study

Background

Genomic profile of breast cancer metastases (M) may differ from that of the primary tumor (PT). In a multicenter prospective study (ESOPE, NCT 01956552) including 130 patients with biopsies of the first metastatic deposit, we have shown that luminal breast cancers are the most prone to phenotypical subtype changes (Comte et al, ASCO 2016#550). We report here the first results of a comparative PT/M targeted next generation sequencing (NGS) mutational analysis.

Methods

Of 130 patients, 117 paired PT/M samples obtained before any treatment were available for analysis. Targeted Sequencing was done using Illumina Hiseq2500 technology with a custom made 95 breast cancer associated genes panel. Sequence data were aligned to the human reference genome (hg19) using Bowtie2 algorithm. Median depth was 607X and 87% of targets achieved 100X depth. SNVs and indels were called using GATK UnifiedGenotyper. We retained COSMIC confirmed non synonymous, exonic/splice variants and observed at a frequency lower than 0,1% in population. Further confirmation of detected variants was performed with comparison to public databases (cbioportal, tumorportal), and potential pathogenicity was evaluated with 4 different public algorithms. We present here the results obtained from the first 35 matched PT/M samples (liver mets 68%), focusing analysis on 40 genes including PIK3CA (20 genes), ER (6 genes) and MAPK (11 genes) pathways, RUNX1, CDH1 and TP53 genes.

Results

Patients characteristics are representative of patients with first line metastatic breast cancer (Comte et al, ASCO 2016#550). Among the 40 genes analyzed in the 70 samples, we detected 134 somatic mutations (70 in PT and 64 in M) including 15 indels and 119 SNV. Among these 134 mutations there were 74 different mutations (66SNV and 8 indels) classified pathogenic for 26 and of unknown pathogenicity for 48 of them. We detected at least 1 mutation in 31 PT and in 28 M. Median numbers of mutations were 1 in PT (range 1-9) and 1 in M (range1-22) samples (p=0.295, Wilcoxon rank sum test). Top ten mutated genes in PT included PIK3CA, TP53, NCOR1, NF1, GATA3, CDH1, ERBB3, PTEN, HRAS, INPP4B. In M samples, the 10 top genes were PIK3CA, TP53, ERBB3, AKT3, CDH1, ERBB4, GATA3, INPP4B, MET, MTOR. Only 3 ESR1 mutations were detected, including 1 PT/M pair and 1 M. Beyond highly shared PIK3CA and TP53 mutations, overall crude PT/M discordance rate was 31%. Analysis by histological subtypes showed PT and M specific mutational profiles, suggesting a role in ERB gene family (notably ERBB3) and MAPK driven pathways in early metastatic progression. Specific metastatic site analysis suggested enrichment in MAPK pathway mutations in liver metastases when compared to other sites. Variant allelic fractions were globally not significantly different between PT and M samples.

Conclusion

In this prospective multicenter series of systematic biopsies of first metastases, we report a targeted mutational analysis of matched PT and M samples not modified by previous therapy exposure. Early analyses suggest specific genotypical changes according to tumor subtype and/or metastatic site. Extended and updated results will be reported at the meeting.

Citation Format: Cottu PH, Boulai A, Callens C, Baulande S, Legoix-Ne P, Bernard V, Vincent-Salomon A, Benhamo V, Brain EGC, Chemlali W, Campone M, Bachelot TD, Giacchetti S, Bonneterre J, Bidard F-C, Servois V, Comte A, Belin L, Sigal B, Bièche I. Comparison of mutational landscapes of primary breast cancer and first metastatic relapse: Results from the ESOPE study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD1-06.

Abstract P2-01-02: Capturing intra-tumor genetic heterogeneity in cell-free plasma DNA from patients with oligometastatic breast cancer

Background: The analysis of cell-free tumor DNA (ctDNA) from plasma has been heralded as a non-invasive technique for disease monitoring and as a means to overcome the challenges posed by intra-tumor genetic heterogeneity. ctDNA levels have been shown to correlate with tumor burden in breast cancer patients. Hence, we sought to define whether massively parallel sequencing of cell-free plasma DNA would capture the entire repertoire of somatic mutations present in the primary tumors and/ or metastases from patients with oligometastatic breast cancer.

Methods: Frozen diagnostic biopsies from primary tumors and their distant metastases were obtained from five prospectively accrued treatment-naïve patients with stage IV breast cancer at presentation (1 estrogen receptor (ER)+/HER2+, 2 ER+/HER2-, 2 ER-/HER2+). A second, independent formalin-fixed paraffin-embedded (FFPE) diagnostic biopsy was obtained from the primary tumor and metastasis from 4 patients. Plasma samples were obtained from all patients. DNA samples from microdissected frozen tumors and peripheral blood, as well as plasma from one patient, were subjected to high-depth whole exome sequencing. DNA samples from all biopsies (frozen/FFPE), plasma and peripheral blood were subjected to targeted capture massively parallel sequencing, with baits for all somatic mutations detected by whole exome sequencing and all exons of the 100 genes most frequently mutated in breast cancer. Driver mutations were defined by state-of-the-art bioinformatic methods and literature search.

Results: We identified and confirmed a median of 54 (range 25-75) and 53 (range 26-85) non-synonymous mutations in the primary tumors and metastases from the 5 cases analyzed, respectively. By sequencing the plasma DNA to a median depth of 248x (range 92-431x), state-of-the-art mutation callers revealed 0-4 mutations (0%-8% of mutations) per patient, and direct interrogation of the sequencing data, based on prior knowledge of the mutations present in the lesions, resulted in the identification of 2-18 mutations (3%-38% of mutations) per patient. Of the bona fide driver mutations, 2/3 TP53 mutations, 0/1 PIK3CA hotspot mutation, 0/1 BRCA2 frameshift mutation, 0/1 GATA3 frameshift mutation and 0/1 ERBB3 activating mutation were captured in the plasma DNA. A SMAD4 pathogenic mutation and a TCF7L2 truncating mutation were found in two diagnostic biopsies of metastatic lesions but not in two biopsies of the primary tumors in one patient each. Whilst the SMAD4 mutation was detected in the plasma DNA from the respective patient, the TCF7L2 mutation was not. Of the 62 mutations restricted to the primary tumors (0-42 per patient) and 74 restricted to the metastatic tumors (1-41 per patient), 4 and 7, respectively, were captured in the plasma DNA.

Conclusions: Massively parallel sequencing assessment of plasma DNA allows for the identification of mutations found in primary tumors and/ or their metastases, however, only a subset of these could be detected at up to 431x depth. These observations suggest that current approaches for whole exome or targeted massively parallel sequencing may not be sufficient to capture the genetic heterogeneity of breast cancers in patients with oligometastatic disease.

Citation Format: Ng CKY, Bidard F-C, Piscuoglio S, Lim RS, Pierga J-Y, Cottu P, Vincent-Salomon A, Viale A, Norton L, Sigal B, Weigelt B, Reis-Filho JS. Capturing intra-tumor genetic heterogeneity in cell-free plasma DNA from patients with oligometastatic breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-01-02.

Response to dual HER2 blockade in a patient with HER3-mutant metastatic breast cancer

BACKGROUND

HER3 activating mutations have been shown in preclinical models to be oncogenic and ligand-independent, but to depend on kinase-active HER2.

PATIENTS AND METHODS

Whole-exome sequencing of the primary HER2-negative breast cancer and its HER2-negative synchronous liver metastasis from a 46-year-old female revealed the presence of an activating and clonal HER3 G284R mutation.

RESULTS

HER2 dual blockade with trastuzumab and lapatinib as third-line therapy led to complete metabolic response in 2 weeks and confirmed radiological partial response after 8 weeks. Following the resection of the liver metastasis, the patient remains disease-free 40 weeks after initiation of the HER2 dual blockade therapy. Immunohistochemical analysis demonstrated a substantial reduction of phospho-rpS6 and phospho-AKT in the post-therapy biopsy of the liver metastasis.

DISCUSSION

This is the first-in-man evidence that anti-HER2 therapies are likely effective in breast cancers harboring HER3 activating mutations.

Abstract S6-06: High-depth massively parallel sequencing reveals heterogeneity between primary tumor and metastatic deposits in de novo metastatic breast cancer patients prior to exposure to systemic therapy

Background: Breast cancers are often composed of mosaics of tumor cells that in addition to the founder genetic events harbor private genetic aberrations. Previous studies comparing the repertoire of mutations in primary breast cancers and their metachronous metastatic deposits that developed after systemic therapy revealed differences in their clonal composition and mutational repertoire. It is unclear, however, whether the differences documented could be attributed to the metastatic process itself or because of selective pressure from systemic therapies. Hence we sought to investigate whether the metastatic process would constitute a biological ‘bottleneck’ resulting in the selection of clones fittest to metastasize. We subjected primary breast cancers and their synchronous metastatic deposits from patients who presented with de novo metastatic disease and who had not received any systemic therapy to gene copy number analysis and high-depth massively parallel sequencing.

Materials and Methods: Frozen primary tumor and distant metastases biopsies were obtained from 7 patients with de novo metastatic disease (i.e. stage IV breast cancer at presentation) enrolled in the ESOPE study (Institut Curie, Paris). DNA samples extracted from microdissected tumors and from peripheral blood were subjected to high-depth (250x) whole exome sequencing and SNP6 copy number profiling. The impact of spatial heterogeneity was further assessed by targeted sequencing of paraffin-embedded samples from additional, independent pre-treatment biopsies of the primary tumor and matched metastasis from the same patients. Driver mutations were defined by bioinformatic methods; for single nucleotide variants (SNVs), CHASM and FATHMM were employed and for insertions/ deletions (indels), only frameshift or truncating mutations in genes normally expressed in breast tissue were included.

Results: In de novo metastatic breast cancers, without any pretreatment, significant genomic differences were observed between primary and metastatic deposits in all cases. A median number of 105 (32-224) and 54 (10-57) SNVs and indels were found, respectively, of which 36 (9-139) and 11 (1-19) were shared between the primary tumors and the de novo metastases, respectively. Although a substantial proportion of driver SNVs and indels were found in common between primary tumors and their respective metastatic deposits (median: 29% (17%-38%)), 50% (25%-78%) of driver SNVs and 79% (60%-90%) of the potentially pathogenic indels were restricted either to the primary or the metastatic deposit, including driver mutations affecting epithelial-to-mesenchymal transition (EMT)-related genes in 3 patients, namely TGFB1, SMAD4 and TCF7L2.

Conclusions: This is, to the best of our knowledge, the first study reporting on the differences in the mutational repertoire between primary tumors and metastatic deposits in de novo metastatic breast cancer patients who have not received systemic therapy. Our findings suggest that the breast cancer metastatic process likely constitutes a biological bottleneck with selection of subclones harboring specific driver genetic aberrations, often affecting EMT-related genes.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S6-06.

Abstract P3-06-04: Role of pMAPkinase, pAKT, p27 & IGF-IR as predictive markers of response to trastuzumab in patients with HER2-positive invasive breast cancer treated with neoadjuvant chemotherapy + trastuzumab in the REMAGUS02 trial

Background: Predicting a benefit from trastuzumab in patients with HER2+ breast cancer remains an important goal. Possible mechanisms of resistance include altered receptor antibody interaction, Akt and MAPK pathways, and loss of p27. The objective of this study was to determine the correlation between pMAPkinase (pMAPK), pAKT, p27, IGF-IR protein expression and the benefit of trastuzumab for patients randomized to chemotherapy (CT) alone and CT with trastuzumab.

Patients and methods: From May 2004 to October 2007, 120 patients with stage II and III HER2+ breast carcinomas were enrolled in a phase II trial of neoadjuvant chemotherapy (CT) with epirubicin-cyclophosphamide (4 courses) followed by docetaxel ± trastuzumab (T) (4 courses). A complete pathological response (pCR) was defined by the absence of residual invasive carcinoma in the breast and axillary lymph nodes. A tissue microarray was constructed from paraffin-embedded tumor samples collected prior to neoadjuvant chemotherapy. Patients' tumours were scored HER2 3+ immunohistochemically (IHC) or 2+ IHC with HER2 amplification by FISH. Immunohistochemical analysis of pMAPK, pAKT, p27 and IGF-IR was performed on tumor tissue microarrays before CT. The H-score (intensity × %) was evaluated. Specimens were classified as exhibiting high or low expression based on a median value as the cut-off point for each marker. A logistic regression model, including the marker and its interaction with treatment, was used to analyse the markers predictive of a treatment effect on the pCR. The independent predictive value was analysed in a multivariate logistic regression adjusting on the lymph node and ER status.

Results: 117/120 (97.5%) patients had sufficient tumor for the analysis. The pCR rate was 19% in the CT arm and 25% in the CT+T arm. The median H-score was: pMAPK = 28, pAKT= 25, p27= 50 and IGF-IR = 15. No significant difference was observed in the pCR rate between the two arms according to pAKT, p27, IGF-IR expression. The pCR rate was higher in CT+T compared to CT alone in patients with high pMAPK expression (OR = 4.7 (0.9–24.2); interaction p = 0.03). No difference was observed in the pCR rate in patients with low pMAPK expression (OR = 0.5 (0.1–1.8).

Conclusions: In HER2-positive breast cancers, pMAPK expression evaluated by IHC was significantly associated with a pathological response in the arm with neoadjuvant trastuzumab. High pMAPK expression could be a predictive marker of response to trastuzumab in a CT +T regimen.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-06-04.

Abstract P1-14-18: Overall survival results of a multicenter randomized phase II study in locally advanced breast cancer patients treated with or without celecoxib for HER2 negative tumor (Remagus 02 trial)

Background: Cox 2 is frequently over expressed in breast cancers. Celecoxib is a COX-2 inhibitor with anti angiogenic and pro-apoptotic activities. There are few data of anti-COX2 treatment in breast cancers. and no data on the impact of neoadjuvant anti COX 2 agent on survival.

Patients and methods/: From May 2004 to October 2007, 340 stage II-III breast cancer patients were included in a phase II randomized trial and received 4 cycles (c) of epirubicin (75 mg/m2)–cyclophosphamide (750 mg/m2) q 3 w followed by 4 (c) of docetaxel (100 mg/m2) q 3 w. Pts with HER2 negative tumors (220 pts) were randomized to receive or not neoadjuvant celecoxib (200 mg bid) combined with docetaxel. All pts with hormone receptors positive tumor received hormonal treatment according to menopausal status (Pierga et al BCRT 2010). We report here overall survival (OS) and disease free survival (DFS) data and prognostic factors analyses at 5 years.

Results/: At a median follow up of 49 months, the median DFS and OS are not reached for the whole population and none of them is significantly different between pts who received celecoxib or who did not (p = respectively 0.62 and 0.36). Celecoxib had no impact either on clinical and pathological complete response rate (pCR). DFS is significantly higher in patients who achieved pCR as compared to those who did not (p = 0.017; RR = 0.21 [0.051–0.88], whereas OS is borderline significant [p = 0.07; RR = 0.19 (0.026–1.4)]. Patients with triple negative (TN) tumors (78 pts) achieved worst DFS (p = 0.02) and OS (p <0.001) than non triple negative ones despite their higher pCR rate, 29.5 % [95 % CI 19;7-40;9 %] vs 11.4 % in all the other subgroups. At multivariate analysis including 7 factors [tumor size, clinical lymph node, grade (1 vs. 2and 3), pCR, ER, PR, TN], factors which influenced OS and DFS were pCR (p = 0.034 & 0.013 and PgR expression (p = 0.046 & 0.01).

Conclusion/: Celecoxib had no influence on pCR, DFS or OS. Despite higher pCR rate triple negative breast cancer patients' subgroup remains with the poorest outcome.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-14-18.

P4-09-13: External Validation of Adjuvant! Online Breast Cancer Prognosis Tool. Improvement Is Still Needed

Introduction: AdjuvantOnline is a web-based application designed to provide 10 years survival probability patients with breast cancer. Few validation studies have underlined some limitations, particularly an overestimation of the prognosis among certain subgroups of patients. Moreover, several predictors such as HER2 over expression status and proliferation markers have not been assessed in Adjuvant! original study. We provide the validation of AdjuvantOnline algorithm on two breast cancer datasets collected from two large European cancer centres, and we determined whether the accuracy of AdjuvantOnline is improved by others well known prognostic factors.

Material and Methods: The French data set is composed of 456 women with early breast cancer, treated at the Institut Curie between 1995 and 1996. The dutch data set is composed of 295 women less that 52 years treated at the Netherlands Cancer Institute between 1984 and 1995. Agreement between observation and Adjuvant! prediction was checked by testing that the calibration slope was equal to 1. Logistic models were performed to evaluate whether risk factors adds significant prognostic information, including AdjuvantOnline a priori information as an offset.

Results: Ten years survival status was known for 383 patients in the French data set and 247 patients in the Dutch data set. Adjuvant! prediction was globally well calibrated in the French data set (observed survival 86%, predicted survival 85%), but was overestimated in high grade, HER2 positive and Ki67 > 20% subgroups. HER2 status, Mitotic Index, Ki67 and treatment type were strongly associated with 10-year survival, even considering AdjuvantOnline a priori information. In the Dutch data set, the overall 10-year survival was overestimated by AdjuvantOnline (observed 66%, predicted 79%), particularly in patients less than 40 years old.

Conclusion: AdjuvantOnline needs to be updated to adjust overoptimistic results in young and high grade patients, and should consider candidates, such as Ki67, HER2 and Mitotic Index.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-09-13.

Effects of crystalloid solutions on circulating lactate concentrations: Part 1. Implications for the proper handling of blood specimens obtained from critically ill patients

OBJECTIVES

a) To test the hypothesis that circulating lactate concentrations are the same in simultaneously collected arterial and central venous blood specimens; b) to test the hypothesis that even small amounts of crystalloid solutions, which are inadequately "cleared" from these indwelling arterial and venous catheters, can lead to clinically important and misleading changes in the measured lactate values.

DESIGN

A prospective, multiexperiment study.

SETTING

A critical care research laboratory and a 20-bed intensive care unit (ICU).

PATIENTS

Three hundred fifty-five patients.

INTERVENTIONS

Blood samples were collected.

MEASUREMENTS AND MAIN RESULTS

Experiment 1: Simultaneously collected arterial and central venous blood specimens were obtained on 148 occasions from 48 medical ICU patients receiving no lactated Ringer's solution (RL). Arterial and central venous lactate values were nearly identical in these patients. The correlation between the arterial and central venous lactate concentrations was excellent (r2 = .85; p < .0001) and the agreement between the arterial and central venous lactate concentrations was also excellent (bias and precision = 0.04 mmol/L and +/- 0.38 mmol/L, respectively). Experiment 2: Arterial and mixed venous blood samples were obtained from 100 percutaneous transluminal coronary angioplasty (PTCA) and 75 cardiac surgical patients immediately before the performance of these cardiac procedures. We found the central venous lactate concentrations to be higher than arterial lactate values in the cardiac surgical group, and there was a very poor correlation (r2 = .07) between arterial and central venous lactate values in the cardiac surgical group. The correlation between central venous and arterial lactate concentrations in the PTCA patients was excellent (r2 = .84) and similar to the findings of experiment 1. Since the cardiac surgical patients received RL and the PTCA patients received no RL, we speculated that the intravenous infusion of RL in the cardiac surgical group accounted for these discordant findings. To test this speculation, we performed experiments 3 and 4. Experiment 3: In a large bench study, blood specimens were divided into multiple 1-mL aliquot portions, to which 0.01, 0.05, 0.10, 0.50, or 1.0 mL of various crystalloid solutions, containing or not containing RL, were added. In a volume-dependent and linear manner, solutions containing RL increased the circulating lactate concentration from 10% to > 400% of the baseline lactate value. In a volume-dependent and linear fashion, the non-RL crystalloid solutions decreased the lactate concentration by 0 to 66% of the baseline nondiluted lactate concentration. Experiment 4: In 30 different cardiac surgical patients, we simultaneously obtained central venous and arterial blood specimens. Patients this time received no RL, and catheter lines were adequately cleared (removal > 5 mL) of crystalloid solutions. We found a correlation (r2 = .82; p < .0001) that was virtually identical to the findings of experiment 1 and to the findings in the PTCA group of experiment 2.

CONCLUSIONS

a) Arterial and central venous lactate concentrations are similar in hemodynamically stable critically ill patients, b) Even small amounts of RL-containing solutions in catheters used for blood sampling may cause false increases in the circulating lactate concentration. c) Even small amounts of non-RL crystalloid solutions in catheters used for blood sampling may falsely decrease circulating lactate values. d) When blood specimens are drawn from indwelling catheters, all crystalloid solutions must be cleared from the line.

Use of the glycerin test in the diagnosis of post-traumatic perilymphatic fistulas

A new application of the glycerin test in the diagnosis of post-traumatic perilymphatic fistulas is described. Temporary disappearance of abnormal responses to the fistula and Quix tests and improvement in the hearing occurred. The glycerin test was useful in confirming the diagnosis of post-traumatic perilymphatic fistula in 13 patients in whom fistulas were found at middle ear exploration.