UNASSIGNED: e21103 Background: With availability of targeted therapies, identifying theprimary @entity5 site is increasingly important. This study characterizes the diagnostic utility of the 92-gene molecular cancer classifier, @entity25878 ( @entity25878 ), in conjunction with histopathologic analysis. METHODS: De-identified cases (N=815) submitted for @entity25878 testing were retrospectively analyzed. Sample characteristics including morphology, @entity5 grade, IHCs, suspected primary site, and time to completion (TTC) were abstracted from pathology reports. Pathologic diagnoses were categorized as unknown, single suspected primary, differential (2 or more suspected), or no primary site reported. @entity25878 data included top prediction, probabilities, and TTC. RESULTS: Analysis of 754 (93%) evaluable cases (mean age: 62 yr; 49% male; biopsy site: 22% liver, 17% LN, 13% lung) showed that conventional work-up included a mean of 7 IHCs (median: 7; range: 0-35) and a mean TTC of 7.7 d (median: 4; range: 0-127). @entity5822 (91%), @entity2225 (86%), @entity10922 (76%) were the most common IHCs: 64% underwent all 3. Cases with >7 IHCs had longer TTC than those with <= 7 IHCs (9.3 vs 6.4d, p=.0017). Pathology reports indicated that upon submission for @entity25878 20% of cases had a single suspected primary, 53% a differential diagnosis, 8% were unknown, and 20% had no specified primary site. Cases with >7 IHCs vs <= 7 IHCs were not associated with an increase in single suspected primaries or a reduction in unknown diagnoses. Sample characteristics indicated clinical utility for @entity25878 in cases of metastatic disease, poorly-differentiated @entity5 , and differential diagnoses. @entity25878 predicted a primary site in 91% of cases (median probability: 78%, range: 23-96%; mean TTC: 5.1d). @entity25878 provided a prediction in 93% (n=59) of cases with a pathologic diagnosis of unknown. In differential cases (n=399), @entity25878 resolved the diagnosis in 55% and provided a new primary in 36%. CONCLUSIONS: This large retrospective analysis demonstrated that current diagnostic processes are nonstandardized in approach, interpretation and TTC, and can yieldequivocal results. @entity25878 is an objective, standardized test that may facilitate diagnosis by providing adjunctive molecular data in @entity5 with indeterminate or unknown origin.

Diagnostic utility of molecular profiling for XXXX of uncertain primary.

@entity10922 :: ('7270', 'Gene') :: ['TTF1'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'tumors'] @entity2225 :: ('54474', 'Gene') :: ['CK20'] @entity25878 :: ('MESH:C537985', 'Disease') :: ['CancerTYPE ID', 'CTID'] @entity5822 :: ('3855', 'Gene') :: ['CK7']
@entity5 :: (MESH:D009369,Disease) :: ['cancers']
