Gunda Pristauz

Establishment of tumor‐specific copy number alterations from plasma DNA of patients with cancer

With the increasing number of available predictive biomarkers, clinical management of cancer is becoming increasingly reliant on the accurate serial monitoring of tumor genotypes. We tested whether tumor‐specific copy number changes can be inferred from the peripheral blood of patients with cancer. To this end, we determined the plasma DNA size distribution and the fraction of mutated plasma DNA fragments with deep sequencing and an ultrasensitive mutation‐detection method, i.e., the Beads, Emulsion, Amplification, and Magnetics (BEAMing) assay. When analyzing the plasma DNA of 32 patients with Stage IV colorectal carcinoma, we found that a subset of the patients (34.4%) had a biphasic size distribution of plasma DNA fragments that was associated with increased circulating tumor cell numbers and elevated concentration of mutated plasma DNA fragments. In these cases, we were able to establish genome‐wide tumor‐specific copy number alterations directly from plasma DNA. Thus, we could analyze the current copy number status of the tumor genome, which was in some cases many years after diagnosis of the primary tumor. An unexpected finding was that not all patients with progressive metastatic disease appear to release tumor DNA into the circulation in measurable quantities. When we analyzed plasma DNA from 35 patients with metastatic breast cancer, we made similar observations suggesting that our approach may be applicable to a variety of tumor entities. This is the first description of such a biphasic distribution in a surprisingly high proportion of cancer patients which may have important implications for tumor diagnosis and monitoring.

Anhydramnios associated with administration of trastuzumab and paclitaxel for metastatic breast cancer during pregnancy

A 38-year-old women in her second pregnancy presented with symptomatic metastatic spinal-cord compression 7 years after undergoing lumpectomy and axillary dissection for stage I primary breast cancer. Immunohistochemistry analysis of the tumour had shown that it was oestrogen-receptor negative, progesterone-receptor positive, and overexpressed ERBB2. The patient had received six cycles of cyclophosphamide, methotrexate, and fl uorouracil followed by radiotherapy and then tamoxifen, which she had taken for 5 years. 86 months after primary diagnosis the patient developed paresthesia and hypoesthesia of the left arm and pain in the cervical vertebrae. MRI showed diff use metastatic infi ltration of the corpus of the second cervical vertebra (fi gure 1) with spinal-cord compression. Additional lesions in the fourth thoracic vertebra and the left femur were also seen with bone scintigraphy, but no other signs of metastatic disease were identifi ed by clinical examination, chest radiograph, or abdominal ultrasound. At this time the patient was 17 weeks pregnant with normal fetal development. After counselling the patient decided to continue pregnancy and was started on hydromorphone hydrochloride. Palliative radiotherapy of 46 Gy given in 23 fractions was administered to the cervical vertebra, which resulted in clinically improved neurological symptoms and pain. Cervical radiotherapy was undertaken with lead shielding of the uterus to protect the fetus. At 25+6 weeks’ gestation the patient received trastuzumab (8 mg/kg loading dose) combined with 175 mg/m of paclitaxel, followed by another cycle at 28+5 weeks with the dose of trastuzumab reduced to 6 mg/kg and the dose of paclitaxel kept the same. Close fetal surveillance was undertaken. Between 26 weeks’ gestation and 32 weeks’ gestation, during two cycles of trastuzumab and paclitaxel, fetal abdominal circumference stopped increasing and the volume of amniotic fl uid decreased to almost anhydramnios (fi gure 2). The mother was of normal constitutional size with normal weight gain of 11 kg during pregnancy and no other risk factors for restriction of intrauterine growth. Tests for premature rupture of the membranes were negative. At 31+6 weeks the volume of both fetal kidneys was decreased below the fi fth percentile. Additionally, the urinary bladder was barely visible, suggesting reduced renal function, and doppler sonography showed increased resistance indices of both the renal arteries (fi gure 3). Doppler sonography of the fetal umbilical and maternal uterine arteries was normal, which suggested healthy placental function. Serial ultrasound measurements of femur length, biparietal diameter, and head circumference were all within normal limits. As a result of the evidence of fetal renal failure and cessation of abdominal growth, fetal lung maturation was induced with corticosteroids after two cycles of trastuzumab and paclitaxel, and a caesarean section was done at 32+1 weeks’ gestation. The male newborn infant weighed 1460 g (tenth percentile), had a body length of 39 cm, and had a head circumference of 29.5 cm. The pH value of the umbilical artery was 7.31. The placenta weighed 290 g and placental histology was normal. The newborn infant showed signs of bacterial sepsis with hypotension, transient renal failure, respiratory failure necessitating mechanical ventilation, and positive laboratory fi ndings (C-reactive protein 30 mg/dL). With antibiotic treatment blood pressure normalised after 2 days and mechanical ventilation was ended on day 6. Diuresis was adequate with serum creatinine slightly increased (1.6 mg/dL) until day 14. Ultrasonography of the fetal kidneys showed transient hyperechodensities in the renal parenchyma that resolved by day 28. These transient hyperechodensities are often noted in newborn infants with transient renal failure as a result of decreased renal perfusion. Echocardiography and cranial ultrasound examinations were normal. The infant was discharged at age 6 weeks weighing 2335 g and in healthy condition. Development at 12 weeks was normal. Lancet Oncol 2007; 8: 79–81

The dynamic range of circulating tumor DNA in metastatic breast cancer

IntroductionThe management of metastatic breast cancer needs improvement. As clinical evaluation is not very accurate in determining the progression of disease, the analysis of circulating tumor DNA (ctDNA) has evolved to a promising noninvasive marker of disease evolution. Indeed, ctDNA was reported to represent a highly sensitive biomarker of metastatic cancer disease directly reflecting tumor burden and dynamics. However, at present little is known about the dynamic range of ctDNA in patients with metastatic breast cancer.MethodsIn this study, 74 plasma DNA samples from 58 patients with metastasized breast cancer were analyzed with a microfluidic device to determine the plasma DNA size distribution and copy number changes in the plasma were identified by whole-genome sequencing (plasma-Seq). Furthermore, in an index patient we conducted whole-genome, exome, or targeted deep sequencing of the primary tumor, metastases, and circulating tumor cells (CTCs). Deep sequencing was done to accurately determine the allele fraction (AFs) of mutated DNA fragments.ResultsAlthough all patients had metastatic disease, plasma analyses demonstrated highly variable AFs of mutant fragments. We analyzed an index patient with more than 100,000 CTCs in detail. We first conducted whole-genome, exome, or targeted deep sequencing of four different regions from the primary tumor and three metastatic lymph node regions, which enabled us to establish the phylogenetic relationships of these lesions, which were consistent with a genetically homogeneous cancer. Subsequent analyses of 551 CTCs confirmed the genetically homogeneous cancer in three serial blood analyses. However, the AFs of ctDNA were only 2% to 3% in each analysis, neither reflecting the tumor burden nor the dynamics of this progressive disease. These results together with high-resolution plasma DNA fragment sizing suggested that differences in phagocytosis and DNA degradation mechanisms likely explain the variable occurrence of mutated DNA fragments in the blood of patients with cancer.ConclusionsThe dynamic range of ctDNA varies substantially in patients with metastatic breast cancer. This has important implications for the use of ctDNA as a predictive and prognostic biomarker.

Neonatal outcome and two-year follow-up after expectant management of second trimester rupture of membranes

Objective: To assess neonatal outcome and 2‐year follow‐up of pregnancies complicated by second trimester preterm premature rupture of membranes (PPROM). Methods: A retrospective review of obstetric and neonatal records for 87 pregnancies (56 singletons, 6 twins, 1 triplet) with PPROM between 14 + 0 and 24 + 6 weeks of gestation. Patients received antibiotics and steroids for fetal lung maturity once they reached 24 weeks of gestation. Placentas were examined histopathologically. Surviving infants were followed‐up at 2 years of age. Results: Median latency from PPROM to delivery was 4 days. Survival rate of 56 singletons was 45% (25/56); and 13 died in hospital. Survival rate of infants discharged from hospital was 23% (12/56). Chorioamnionitis was seen histologically in 42% (5/12) of surviving infants compared with 92% (12/13) of those that died in hospital. Of the 12 surviving infants, 50% had a normal neurological and developmental outcome at 2 years of age. Conclusion: Gestational age, birth weight, and histologic chorioamnionitis have prognostic importance in pregnancies complicated by PPROM. Surviving infants have a 50% chance of achieving an adequate health status at 2 years of age.

Inferring expressed genes by whole-genome sequencing of plasma DNA

The analysis of cell-free DNA (cfDNA) in plasma represents a rapidly advancing field in medicine. cfDNA consists predominantly of nucleosome-protected DNA shed into the bloodstream by cells undergoing apoptosis. We performed whole-genome sequencing of plasma DNA and identified two discrete regions at transcription start sites (TSSs) where nucleosome occupancy results in different read depth coverage patterns for expressed and silent genes. By employing machine learning for gene classification, we found that the plasma DNA read depth patterns from healthy donors reflected the expression signature of hematopoietic cells. In patients with cancer having metastatic disease, we were able to classify expressed cancer driver genes in regions with somatic copy number gains with high accuracy. We were able to determine the expressed isoform of genes with several TSSs, as confirmed by RNA-seq analysis of the matching primary tumor. Our analyses provide functional information about cells releasing their DNA into the circulation.

Androgen receptor expression in breast cancer patients tested for BRCA1 and BRCA2 mutations.

Pristauz G, Petru E, Stacher E, Geigl J B, Schwarzbraun T, Tsybrovskyy O, Winter R & Moinfar F
(2010) Histopathology57, 877–884

How accurate is frozen section histology of pelvic lymph nodes in patients with endometrial cancer

OBJECTIVE Recent prospective data support the trend towards systematic retroperitoneal lymphadenectomy in patients with high-risk endometrial cancer. Because para-aortic node involvement in the absence of pelvic node involvement is uncommon, a reliable finding of negative pelvic lymph nodes (PLN) at intraoperative frozen section examination might allow omitting para-aortic dissection. We analyzed the diagnostic accuracy of frozen section examination of PLN in patients with endometrial cancer. METHODS We reviewed 131 patients with endometrial cancer who underwent surgery including systematic pelvic lymphadenectomy (n=101) or pelvic and para-aortic lymphadenectomy (n=27). Intraoperative frozen section examination of PLN was performed in 72 (55%) patients. Results of frozen section examination were compared with those of final histopathology and the diagnostic accuracy of frozen section examination of PLN was calculated. One pathologist measured the diameters of PLN metastases retrospectively. RESULTS A total of 1063 and 2666 PLN were analyzed by frozen section examination and by final histopathology, respectively. PLN metastases were found in 7 cases (10%) at frozen section examination, and in 17 cases (24%) at final histopathology (false negative rate, 59%). No false positive cases were noted. The mean diameter of all PLN metastases at final histopathology was 4.3 mm, as compared to 9.0 mm for the metastases detected at frozen section analyses. The mean diameter of PLN metastases missed at frozen section examination was 2.0 mm. CONCLUSION In this review at a single institution, intraoperative frozen section histology missed nearly two of three endometrial cancer patients with positive nodes. These results do not support tailoring the extent of lymphadenectomy according to the results of frozen section examination.

Clinical Practice Guideline for the prevention and early detection of breast and ovarian cancer in women from HBOC (hereditary breast and ovarian cancer) families.

SummaryAn estimated 10 % of breast cancer cases exhibit a higher familial incidence, and functional mutations in BRCA (breast cancer-gene) 1 or 2 are responsible for the development of malignant tumors in approximately half of these cases. Women with a germline mutation in either of the two genes have a lifetime risk of up to 85 % to develop breast cancer, and of up to 60 % risk to develop ovarian cancer. This clinical practice guideline defines the individual and familial tumor constellations that represent an indication for BRCA germline testing. It also describes the therapeutic options (early detection programme vs prophylactic surgery) that arise from the result of a BRCA mutational analysis. This guideline further includes recommendations regarding the use of multigene panels and therapeutic aspects that arise from the selective use of poly ADP ribose polymerase (PARP) inhibitors in patients with known BRCA1 or 2 mutations. It replaces the previous version of the “Clinical Practice Guideline for the Prevention and Early Detection of Breast- and Ovarian Cancer in women from HBOC (hereditary breast and ovarian cancer) families” which was published in 2012.

Leitlinie zur Prävention und Früherkennung von Brust- und Eierstockkrebs bei Hochrisikopatientinnen, insbesondere bei Frauen aus HBOC (Hereditary Breast and Ovarian Cancer) Familien

ZusammenfassungDie vorliegende österreichische Leitlinie zur Prävention und Früherkennung von Brust- und Eierstockkrebs bei Hochrisikopatientinnen – insbesondere bei Frauen aus HBOC-Familien – wurde unter der besonderen Berücksichtigung des aktuellen EUSOMA (European Society of Breast Cancer Specialists) Positionspapiers von oben angeführten Experten gemeinsam erstellt. Die Leitlinie soll die Betreuung von Frauen mit einem erhöhtem Lebenszeitrisiko für Brust- und/oder Eierstockkrebs standardisieren und vereinfachen.SummaryThe Austrian guideline for prevention and early detection of breast and ovarian cancer in high risk patients—particularly in women from hereditary breast and ovarian cancer families—were established with particular consideration of the most recent position paper of the European Society of Breast Cancer Specialists (EUSOMA) by the authors mentioned above. The guideline is aimed at facilitating and standardizing the care and early detection strategies in women with an elevated life time risk for breast and ovarian cancer.The Austrian guideline for prevention and early detection of breast and ovarian cancer in high risk patients--particularly in women from hereditary breast and ovarian cancer families--were established with particular consideration of the most recent position paper of the European Society of Breast Cancer Specialists (EUSOMA) by the authors mentioned above. The guideline is aimed at facilitating and standardizing the care and early detection strategies in women with an elevated life time risk for breast and ovarian cancer.

Assessment of risk factors for survival of neonates born after second-trimester PPROM.

OBJECTIVE Assess fetal risk factors which impact survival of infants delivered after second-trimester PPROM. STUDY DESIGN Clinical records of 87 patients, who all had second-trimester rupture of membranes between 14+0 and 24+6 weeks of gestation treated January 1998 to July 2005 were reviewed regarding perinatal outcome. This study is based on 25 surviving infants. RESULTS 13 of these 25 infants died in the hospital. Survivors had a higher birth weight (p=0.008) and higher Apgar scores after 5 min (p=0.005) than those infants dying. No differences in UA pH, the need of catecholamines and no association between histological verified chorioamnionitis and early onset sepsis were seen between survivors and nonsurvivors. CONCLUSION Higher gestational age at birth, higher birth weight, the absence of histologically verified chorioamnionitis and 5 min Apgar scores of >or= than 6 have positive prognostic value for survival of neonates delivered preterm after second-trimester PPROM.