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PURPOSE Tissue-based comprehensive genomic profiling (CGP) is increasingly used for treatment selection in patients with advanced cancer; however, tissue availability may limit widespread implementation. Here, we established real-world CGP tissue availability and assessed CGP performance on consecutively received samples. MATERIALS AND METHODS We conducted a post hoc, nonprespecified analysis of 32,048 consecutive tumor tissue samples received for StrataNGS, a multiplex polymerase chain reaction (PCR)–based comprehensive genomic profiling (PCR-CGP) test, as part of an ongoing observational trial ( NCT03061305 ). Sample characteristics and PCR-CGP performance were assessed across all tested samples, including exception samples not meeting minimum input quality control (QC) requirements (< 20% tumor content [TC], < 2 mm2 tumor surface area [TSA], DNA or RNA yield < 1 ng/µL, or specimen age > 5 years). Tests reporting ≥ 1 prioritized alteration or meeting TC and sequencing QC were considered successful. For prostate carcinoma and lung adenocarcinoma, tests reporting ≥ 1 actionable or informative alteration or meeting TC and sequencing QC were considered actionable. RESULTS Among 31,165 (97.2%) samples where PCR-CGP was attempted, 10.7% had < 20% TC and 59.2% were small (< 25 mm2 tumor surface area). Of 31,101 samples evaluable for input requirements, 8,089 (26.0%) were exceptions not meeting requirements. However, 94.2% of the 31,101 tested samples were successfully reported, including 80.5% of exception samples. Positive predictive value of PCR-CGP for ERBB2 amplification in exceptions and/or sequencing QC-failure breast cancer samples was 96.7%. Importantly, 84.0% of tested prostate carcinomas and 87.9% of lung adenocarcinomas yielded results informing treatment selection. CONCLUSION Most real-world tissue samples from patients with advanced cancer desiring CGP are limited, requiring optimized CGP approaches to produce meaningful results. An optimized PCR-CGP test, coupled with an inclusive exception testing policy, delivered reportable results for > 94% of samples, potentially expanding the proportion of CGP-testable patients and impact of biomarker-guided therapies.

Spontaneous bleeding in adults is a major problem, and in a significant number of these patients no cause is found. A 63-year-old Caucasian man presented to our hematology clinic with a large hematoma of his left thigh. Initial investigations did not show any conclusive abnormalities of primary or secondary hemostasis. Subsequent tests demonstrated a type 1 deficiency of antiplasmin. Treatment with low doses of epsilon-aminocaproic acid resulted in resolution of the hematoma and control of bleeding. We sought to determine the cause of the patient's isolated antiplasmin deficiency but no explanation was found. Three heterozygous polymorphisms were identified in his antiplasmin gene, ruling out major gene deletions. Each of these three polymorphisms has been previously reported in healthy blood donors. Finally, since response to antifibrinolytics can be dramatic, deficiencies of antiplasmin must be considered in patients presenting at any age with a spontaneous bleeding disorder.

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Spontaneous disruption of hemostasis in adults is a common clinical presentation. However, in a few patients, no cause is found. We were faced with such a situation when a 63 year old Caucasian male presented with a large spontaneous hematoma of his left thigh. There was no prior history of bleeding disorders in our patient or amongst his family members. Initial investigations did not show any conclusive coagulation factor abnormalities. Fibrinogen, D-dimer, liver function tests and platelet aggregation studies were normal. Subsequent tests showed that while his activatable plasminogen and euglobin clot lysis were normal, the function of his alpha-2 antiplasmin was at 35% of normal. Laurell immunoassay demonstrated a type 1 deficiency with antigen levels proportionately decreased at 30% of normal. Treatment with low dose epsilon amino caproic acid resulted in resolution of the hematoma and control of bleeding. We therefore sought to determine the cause of his isolated alpha-2 antiplasmin deficiency. Alpha-2 antiplasmin is a serpin which targets plasmin. It is synthesized in the liver and deficiency results in a bleeding disorder.Congenital deficiencies of alpha-2 antiplasmin are uncommon bleeding disorders. However, since heterozygotic mutations of alpha-2 antiplasmin can present with initial bleeds late in life, we sequenced his alpha-2 antiplasmin gene. This gene is located on chromosome 17, spanning 16 Kb. It has 10 exons which we amplified by PCR in 13 segments and sequenced by the di-deoxy method. All splice junctions and the 70 base pairs upstream of exon 1 were normal. Three heterozygous polymorphisms were found, ruling out major gene deletions. The polymorphisms are as follows: Exon 2, C to T causing substitution of Alanine by Valine in the signal peptide, Exon 3, C to T causing substitution of Arginine by Tryptophan, Exon 10, G to A causing substitution of Arginine by Lysine. Each of these 3 polymorphisms have been found in blood donors. This raises important issues about his deficiency. First, lack of production could be due to defective translational factors or epigenetic factors regulating gene transcription. It could also be due to the Alanine to Valine change in the signal peptide which we are currently investigating. Secondly, non-inhibitory antibodies to alpha-2 antiplasmin could explain his type 1 deficiency. Finally, age-related vascular and connective tissue defects may unmask a dormant inherited bleeding disorder. Unfortunately, his demise due to the development of nephrotic syndrome and sepsis may leave us without answers to these questions. There is no case linking nephrotic syndrome with the use of epsilon amino caproic acid. In conclusion, since response to anti- fibrinolytics can be dramatic, deficiencies of alpha-2 antiplasmin must be considered in patients presenting at any age with a spontaneous bleeding disorder.