Clinicopathologic and Genomic Characterization of PD-L1 Positive Urothelial Carcinomas.

INTRODUCTION: Pembrolizumab was approved with an accompanying companion diagnostic (CDx) assay (PD-L1 DAKO 22C3) for urothelial carcinoma (UC). In this study, we further characterize the clinicopathologic and genomic features of UC that are programmed death-ligand 1 (PD-L1) positive. MATERIALS AND METHODS: The cohort of this study consisted of a total of 528 consecutive UC patients with PD-L1 immunohistochemistry (IHC) and comprehensive genomic profiling (CGP). All PD-L1 IHC testing was performed using the DAKO 22C3 CDx assay for UC. PD-L1 positivity was determined at a combined positive score ≥ 10. RESULTS: A total of 44.5% (235/528) patients with UC were PD-L1positive . A lower PD-L1 positivity rate was detected in primary (42.3%, 148/350) versus metastatic sites (48.9%, 87/178). PD-L1 positivity was dependent on the location of the metastatic sites. CGP revealed PD-L1positive patients had more frequent genomic alterations (GAs) in TP53 (p = .006) and RB1 (p = .003) and less frequent GAs in FGFR3 (p = .001) and MTAP (p = .028). The APOBEC mutational signature and tumor mutational burden (TMB)-high were more common in PD-L1positive patients. By testing patients with UC with CGP, in addition to PD-L1 IHC, an additional 97 patients (18.4%) in the total cohort were eligible for immunotherapy based on TMB status. CONCLUSION: PD-L1positive and PD-L1negative urothelial carcinomas are genomically different. Also, our study provides the framework for future clinical investigation with regard to specimen site selection for PD-L1 testing as well as candidate biomarker genomic alterations that may predict for better response or lack of response to immune checkpoint inhibitors. IMPLICATIONS FOR PRACTICE: In this study, a higher prevalence of TP53 and RB1 alterations and APOBEC mutational signatures in the PD-L1positive urothelial carcinoma disease subset and enrichment of FGFR3 alterations in the PD-L1negative disease subset were found. These data provide the basis for future investigation into the role of these genomic changes as positive and negative predictors of immunotherapy response. Also, differences wer seen in PD-L1 positivity based on the collection site of the sample, which can provide a framework for future clinical trial design and could influence sample selection for PD-L1 testing in patients with urothelial carcinoma when multiple samples are available.

Clinicopathologic and genomic characterization of PD-L1-positive uterine cervical carcinoma.

Positive program death-ligand 1 (PD-L1) immunohistochemistry (IHC) is an approved companion diagnostic guiding the use of immune checkpoint inhibitors in uterine cervical carcinoma (CXC). The clinical and genomic features of PD-L1-positive (PD-L1positive) CXC have not been previously described. We reviewed the clinicopathologic and molecular features of 647 CXC cases that were tested using DAKO 22C3 PD-L1 IHC and comprehensive genomic profiling during the course of clinical care. PD-L1positive cases were defined via a combined positive score of ≥ 1. No differences were found in age, genetic ancestry, and HPV status of the PD-L1positive (n = 548) and PD-L1negative disease subset. The PD-L1 positivity rate varied by histologic subtype of CXC with squamous cell carcinoma (SCC) having a PD-L1 positivity rate of 91% (397/437) and usual-type adenocarcinoma's PD-L1 positivity rate being 60% (35/58). In addition, the PD-L1 positivity rate varied depending on site of the specimen with 89.1% (261/293) positivity rate observed in cervix specimens compared to 25% (2/8) in brain metastases specimens. No significant difference in tumor mutational burden (TMB), microsatellite instability, and CD274 (encoding PD-L1) amplification was observed between PD-L1positive and PD-L1negative CXC subsets. By combining TMB with PD-L1, an additional 17 patients are eligible for pembrolizumab when compared to PD-L1 testing alone. TERT promoter alterations and APOBEC mutational signature were enriched in the PD-L1positive CXC SCC (p = 0.011, and p = 0.004, respectively). Our study reveals important prevalence data on PD-L1 positivity in CXC non-SCC and suggests that further studies in these histologic subtypes are warranted. In addition, we also provide a key framework to guide both specimen selection and future investigations of predictors of immunotherapy response in cervical cancer patients. Lastly, TERT promoter alterations and APOBEC mutational signature may be a biologically unique subset of PD-L1positive CXC SCC.

A pan-cancer analysis of PD-L1 immunohistochemistry and gene amplification, tumor mutation burden and microsatellite instability in 48,782 cases.

PD-L1 immunohistochemistry (IHC) currently has the most Food and Drug Administration (FDA) approvals as a companion diagnostic (CDx) for immunotherapies in specific tumor types; however, multiple other immunotherapy biomarkers exist. We performed this study to examine and report the prevalence of PD-L1 expression in a wide variety of tumor types and examine its relationship to microsatellite instability (MSI), tumor mutational burden (TMB), and CD274 (PD-L1) gene amplification. We performed a retrospective analysis of all cases in which both PD-L1 IHC (using the DAKO 22C3 IHC assay with either tumor proportion score (TPS) or combined positive score (CPS); or the VENTANA SP142 assay with infiltrating immune cell score (IC)) and comprehensive genomic profiling (CGP) were tested at Foundation Medicine between January 2016 and November 2019. Of note, PD-L1 positivity is defined per the CDx indication and tumor proportion score (TPS ≥ 1) for indications without a CDx claim; and TMB positivity is defined as ≥10 mutations/Mb. A total of 48,782 cases were tested for PD-L1 IHC and CGP. Immune cell expression of PD-L1 was more frequently identified than tumor cell expression of PD-L1. We saw a high correlation between PD-L1 expression and CD274 gene amplification (p < 0.0001), MSI and TMB (p < 0.0001), and PD-L1 and TMB (p < 0.0001). In addition, the combination of PD-L1 and TMB identified four unique disease subsets PD-L1-/TMB-, PD-L1+/TMB-, PD-L1-/TMB+, and PD-L1+/TMB+ with varying prevalence dependent on tumor type. Lastly, 50.3% (24527/48782) of the overall cohort was positive for at least one of the CDx or exploratory biomarkers described above. This is the largest pan-cancer analysis of relevant biomarkers associated with response to checkpoint inhibitors to date, including more than 48,000 cases. Additional clinical trials with treatment outcome data in individual tumor types are needed to determine whether the double positive PD-L1+/TMB+ disease subset would respond best to immunotherapy.

Biomarkers in Breast Cancer: An Integrated Analysis of Comprehensive Genomic Profiling and PD-L1 Immunohistochemistry Biomarkers in 312 Patients with Breast Cancer.

BACKGROUND: We examined the current biomarker landscape in breast cancer when programmed death-ligand 1 (PD-L1) testing is integrated with comprehensive genomic profiling (CGP). MATERIAL AND METHODS: We analyzed data from samples of 312 consecutive patients with breast carcinoma tested with both CGP and PD-L1 (SP142) immunohistochemistry (IHC) during routine clinical care. These samples were stratified into hormone receptor positive (HR+)/human epidermal growth factor receptor negative (HER2-; n = 159), HER2-positive (n = 32), and triple-negative breast cancer (TNBC) cohorts (n = 121). RESULTS: We found that in the TNBC cohort, 43% (52/121) were immunocyte PD-L1-positive, and in the HR+/HER2- cohort, 30% (48/159) had PIK3CA companion diagnostics mutations, and hence were potentially eligible for atezolizumab plus nab-paclitaxel or alpelisib plus fulvestrant, respectively. Of the remaining 212 patients, 10.4% (22/212) had a BRCA1/2 mutation, which, if confirmed by germline testing, would allow olaparib plus talazoparib therapy. Of the remaining 190 patients, 169 (88.9%) were positive for another therapy-associated marker or a marker that would potentially qualify the patient for a clinical trial. In addition, we examined the relationship between immunocyte PD-L1 positivity and different tumor mutation burden (TMB) cutoffs and found that when a TMB cutoff of ≥9 mutations per Mb was applied (cutoff determined based on prior publication), 11.6% (14/121) patients were TMB ≥9 mutations/Mb and of these, TMB ≥9 mutations per Mb, 71.4% (10/14) were also positive for PD-L1 IHC. CONCLUSION: Our integrated PD-L1 and CGP methodology identified 32% of the tested patients as potentially eligible for at least one of the two new Food and Drug Administration approved therapies, atezolizumab or alpelisib, and an additional 61.2% (191/312) had other biomarker-guided potential therapeutic options. IMPLICATIONS FOR PRACTICE: This integrated programmed death-ligand 1 immunohistochemistry and comprehensive genomic profiling methodology identified 32% of the tested patients as eligible for at least one of the two new Food and Drug Administration-approved therapies, atezolizumab or alpelisib, and an additional 61.2% (191/312) had other biomarker-guided potential therapeutic options. These findings suggest new research opportunities to evaluate the predictive utility of other commonly seen PIK3CA mutations in hormone receptor-positive breast cancers and to standardize tumor mutation burden cutoffs to evaluate its potentially predictive role in triple-negative breast cancer.

Gastric adenocarcinoma microRNA profiles in fixed tissue and in plasma reveal cancer-associated and Epstein-Barr virus-related expression patterns.

MicroRNA expression in formalin-fixed paraffin-embedded tissue (FFPE) or plasma may add value for cancer management. The GastroGenus miR Panel was developed to measure 55 cancer-specific human microRNAs, Epstein-Barr virus (EBV)-encoded microRNAs, and controls. This Q-rtPCR panel was applied to 100 FFPEs enriched for adenocarcinoma or adjacent non-malignant mucosa, and to plasma of 31 patients. In FFPE, microRNAs upregulated in malignant versus adjacent benign gastric mucosa were hsa-miR-21, -155, -196a, -196b, -185, and -let-7i. Hsa-miR-18a, 34a, 187, -200a, -423-3p, -484, and -744 were downregulated. Plasma of cancer versus non-cancer controls had upregulated hsa-miR-23a, -103, and -221 and downregulated hsa-miR-378, -346, -486-5p, -200b, -196a, -141, and -484. EBV-infected versus uninfected cancers expressed multiple EBV-encoded microRNAs, and concomitant dysregulation of four human microRNAs suggests that viral infection may alter cellular biochemical pathways. Human microRNAs were dysregulated between malignant and benign gastric mucosa and between plasma of cancer patients and non-cancer controls. Strong association of EBV microRNA expression with known EBV status underscores the ability of microRNA technology to reflect disease biology. Expression of viral microRNAs in concert with unique human microRNAs provides novel insights into viral oncogenesis and reinforces the potential for microRNA profiles to aid in classifying gastric cancer subtypes. Pilot studies of plasma suggest the potential for a noninvasive addition to cancer diagnostics.

Displaced granulosa cells in the fallopian tube mistaken for metastatic granulosa cell tumor.

A 44-yr-old woman underwent a total hysterectomy and bilateral salpingectomy secondary to uterine leiomyomas. Gross examination of the fallopian tubes revealed no masses or lesions; however, 2 small foci of granulosa cells were identified microscopically within one of the fallopian tubes. These foci were suspicious for granulosa cell tumor metastases. The patient subsequently underwent a bilateral oophorectomy, which revealed no primary granulosa cell tumor. Immunohistochemical studies were used to help support the benign nature of the granulosa cells within the fallopian tube. A review of the literature revealed only 1 similar case report of displaced benign granulosa cells within the fallopian tubes. The ovaries in both this case and the previous case report were found to contain multiple cystic follicles, suggesting ovulation as the likely mechanism of displacement. Knowledge of this rare occurrence and the use of immunohistochemical staining are paramount to making a correct diagnosis, thus preventing a misdiagnosis of malignancy and possible unnecessary treatment.

Deletions on 9p21 are associated with worse outcomes after anti-PD-1/PD-L1 monotherapy but not chemoimmunotherapy.

NCCN guidelines for first-line treatment of advanced non-squamous non-small-cell lung cancer (NSCLC) patients without targetable driver alterations includes either immunotherapy alone or in combination with chemotherapy. In this study, we investigated genomic predictors of survival after immunotherapy to guide this treatment decision. Cox proportional hazards regression was used to identify genomic correlates of survival in a cohort of EGFR/ALK-, non-squamous NSCLC patients treated with first-line pembrolizumab monotherapy (mono-IO) or pembrolizumab in combination with carboplatin/cisplatin and pemetrexed (chemo-IO) within a real-world clinico-genomic database. The effect of deletions on 9p21 was further evaluated in five additional tumor types. Among mono-IO treated non-squamous NSCLC patients, tumors with 9p21.3 gene deletions (CDKN2A, CDKN2B, MTAP) were associated with worse survival compared to the corresponding deletion-negative tumors (CDKN2A deletion HR = 1.8, P = 0.001). However, this association was not observed among chemo-IO treated patients (CDKN2A deletion HR = 1.1, P = 0.4). This finding remained after adjusting for clinical and genomic features including TMB and PD-L1. Deletions at 9p21.3 were not associated with differences in TMB, PD-L1, or tumor inflammation. Due to the high incidence of 9p21.3 deletions across tumor types, we performed a pan-cancer analysis and found CDKN2A deletion-positive tumors had worse survival following first-line immunotherapy treatment in multiple tumor types (HR = 1.4, P < 0.001). These results indicate deletions at 9p21.3 are a putative negative predictor of clinical benefit from first-line immune checkpoint inhibitors and may have utility in choosing between mono-IO vs chemo-IO regimens in NSCLC.

Landscape of Biomarkers in Non-small Cell Lung Cancer Using Comprehensive Genomic Profiling and PD-L1 Immunohistochemistry.

Comprehensive genomic profiling (CGP) and immunohistochemistry (IHC) are important biomarker tools used for patients with non-small cell lung cancer (NSCLC) given the expanding number of standard-of-care therapies that require companion diagnostic testing. We examined 9450 NSCLC real-world patient samples that underwent both CGP and programmed death-ligand 1 (PD-L1) IHC to understand the biomarker landscape in this patient cohort. By assessing National Comprehensive Cancer Network (NCCN)-recommended biomarkers including genomic alterations, tumor mutational burden (≥10 mutations/Mb cut-off), and PD-L1 expression (Tumor Proportion Score (TPS) ≥ 50% cut-off), we show that CGP + PD-L1 IHC yielded potentially actionable results for 70.5% of the 9,450 patients with NSCLC. Among the remaining 29.5% (2,789/9,450) of patients, 86.7% (2,419/2,789) were potentially eligible for another biomarker-associated therapy and/or clinical trial based on their genomic profile. In addition, in the PD-L1TPS≥50% disease subset, BRAF mutations, MET mutations, MET amplifications, and KRAS mutations were significantly enriched; and in the PD-L1TPS<50%, EGFR mutations, ERBB2 mutations, STK11 mutations, and KEAP1 mutations were enriched. These findings highlight the improved clinical utility of combining CGP with IHC to expand the biomarker-guided therapeutic options available for patients with NSCLC, relative to single biomarker testing alone.

Unexpected interference of baby wash products with a cannabinoid (THC) immunoassay.

OBJECTIVES: The results of newborn drug screening have far-reaching impact not only in healthcare, but also in the legal domain. Therefore, the accuracy of these results cannot be undervalued. When false positive cannabinoid (THC) screening results for this population were suspected at our institution, a multidisciplinary approach was initiated to evaluate the screening process for any pre-analytical or analytical sources of error or interference. DESIGN AND METHODS: Mixtures of drug-free urine with various commercial products and materials that commonly contact newborns in our nursery were prepared and tested using the immunoassay screening methods in our laboratory. Additional commercial products were similarly tested; and when available, individual surfactants common to the interfering products were also evaluated. RESULTS: Addition of Head-to-Toe Baby Wash to drug-free urine produced a dose dependent measureable response in the THC immunoassay. Addition of other commercially available baby soaps gave similar results, and subsequent testing identified specific chemical surfactants that reacted with the THC immunoassay. CONCLUSION: We have identified commonly used soap and wash products used for newborn and infant care as potential causes of false positive THC screening results. Such results in this population can lead to involvement by social services or false child abuse allegations. Given these consequences, it is important for laboratories and providers to be aware of this potential source for false positive screening results and to consider confirmation before initiating interventions. Most importantly, we demonstrate the need for active involvement in the "total testing process," as sources of error are not confined to the laboratory walls.