Homologous recombination repair (HRR) mutation concordance between liquid biopsy (LB) and tumor tissue by NGS in a real-world prostate cancer (PC) database

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Background: NGS to identify HRR mutations (mut) is indicated in advanced prostate cancer (aPC); samples for testing may be tissue or plasma. In a large real-world (RW) database, we determined concordance between plasma ctDNA and primary tumor tissue (PT) and/or metastatic tissue (MT) for BRCA1, BRCA2, and ATM mut in PC patients (pts) who received both LB and tissue NGS any time during standard of care (SOC) management. The study objective was to assess the utility of LB to detect actionable mut in these HRR genes and demonstrate the utility of combined LB and tissue testing. Methods: We examined de-identified data from pts who had NGS using both Tempus xF (105 genes-LB) and Tempus xT (648 genes-tissue) during SOC for aPC. Analyses included 1) PT and LB and 2) MT and LB. The results from the pts’ earliest PT or MT and earliest LB were used for paired analyses. The prevalence of a pathogenic/likely pathogenic germline and/or somatic mut in BRCA1, BRCA2, or ATM was reported as N (%), 95% CI. The sensitivity of the LB to identify observed HRR mut in tissue was also reported as N (%), 95% CI. Concordance between pairs was evaluated by Cohen’s kappa statistic with 95% CI. Results: HRR results are show for 1074 PC pts who had NGS performed on PT and LB and 451 PC pts with NGS on both MT and LB. In the PT and LB analysis, HRR mut were found in 6.2% (95% CI: 4.9%-7.9%) of LB and 8.8% (95% CI: 7.2%-11%) of PT. The sensitivity of LB to detect HRR mut in the PT was 53% (95% CI: 43%-64%). Cohen’s kappa statistic was 0.59, 95% CI=0.50-0.68, between PT and LB. In the MT and LB analysis, HRR mut were found in 10% (95% CI 7.8%-14%) of LB and 10% (7.6%-13%) of MT. The sensitivity of LB to detect HRR mut in the MT was 70% (95% CI: 54%-82%). Cohen’s kappa statistic was 0.65, 95% CI=0.54-0.77, between MT and LB. Conclusions: In this large RW dataset, plasma ctDNA-based analysis of BRCA1, BRCA2, and ATM mut showed greater concordance between LB and MT than LB and PT, and may be used as an initial tool for HRR mut detection. When LB results are negative, further exploration with tissue-based testing may identify HRR mut to guide clinical decisions. [Table: see text]

Single patch super-resolution of histopathology whole slide images: a comparative study

Purpose

The latest generation of scanners can digitize histopathology glass slides for computerized image analysis. These images contain valuable information for diagnostic and prognostic purposes. Consequently, the availability of high digital magnifications like 20 × and 40 × is commonly expected in scanning the slides. Thus, the image acquisition typically generates gigapixel high-resolution images, times as large as 100,000 × 100,000    pixels . Naturally, the storage and processing of such huge files may be subject to severe computational bottlenecks. As a result, the need for techniques that can operate on lower magnification levels but produce results on par with outcomes for high magnification levels is becoming urgent.

Approach

Over the past decade, the digital solution of enhancing images resolution has been addressed by the concept of super resolution (SR). In addition, deep learning has offered state-of-the-art results for increasing the image resolution after acquisition. In this study, multiple deep learning networks designed for image SR are trained and assessed for the histopathology domain.

Results

We report quantitative and qualitative comparisons of the results using publicly available cancer images to shed light on the benefits and challenges of deep learning for extrapolating image resolution in histopathology. Three pathologists evaluated the results to assess the quality and diagnostic value of generated SR images.

Conclusions

Pixel-level information, including structures and textures in histopathology images, are learnable by deep networks; hence improving the resolution quantity of scanned slides is possible by training appropriate networks. Different SR networks may perform best for various cancer sites and subtypes.

Deepfake Histologic Images for Enhancing Digital Pathology

A pathologist's optical microscopic examination of thinly cut, stained tissue on glass slides prepared from a formalin-fixed paraffin-embedded tissue blocks is the gold standard for tissue diagnostics. In addition, the diagnostic abilities and expertise of pathologists is dependent on their direct experience with common and rarer variant morphologies. Recently, deep learning approaches have been used to successfully show a high level of accuracy for such tasks. However, obtaining expert-level annotated images is an expensive and time-consuming task, and artificially synthesized histologic images can prove greatly beneficial. In this study, we present an approach to not only generate histologic images that reproduce the diagnostic morphologic features of common disease but also provide a user ability to generate new and rare morphologies. Our approach involves developing a generative adversarial network model that synthesizes pathology images constrained by class labels. We investigated the ability of this framework in synthesizing realistic prostate and colon tissue images and assessed the utility of these images in augmenting the diagnostic ability of machine learning methods and their usability by a panel of experienced anatomic pathologists. Synthetic data generated by our framework performed similar to real data when training a deep learning model for diagnosis. Pathologists were not able to distinguish between real and synthetic images, and their analyses showed a similar level of interobserver agreement for prostate cancer grading. We extended the approach to significantly more complex images from colon biopsies and showed that the morphology of the complex microenvironment in such tissues can be reproduced. Finally, we present the ability for a user to generate deepfake histologic images using a simple markup of sematic labels.

Surveillance mammography after treatment for male breast cancer

PURPOSE

To identify the practice patterns related to use of surveillance mammography in male breast cancer (MaBC) survivors.

METHODS

Using administrative claims data from OptumLabs Data Warehouse, we identified men who underwent surgery for breast cancer during 2007-2017. We calculated the proportion of men who had at least one mammogram (a) within 13 months for all patients and (b) within 24 months amongst those who maintained their insurance coverage for at least that length of time after surgery. Multivariate logistic regression modeling was used to identify factors associated with mammography within each timeframe.

RESULTS

Out of 729 total MaBC survivors, 209 (29%) underwent mammography within 13 months after surgery. Among those who had lumpectomy, 41% underwent mammography, whereas among those who had mastectomy, 27% had mammography. Amongst 526 men who maintained consistent insurance coverage for 24 months after surgery, 215 (41%) underwent mammography at least once during that 24-month period. In this cohort, the proportion who had at least one mammogram during the 24-month period was 49% after lumpectomy and 40% after mastectomy. In a multivariate logistic regression model, more recent diagnosis (2015+) and older age at diagnosis were associated with lower odds of undergoing mammography, while receipt of radiation was associated with higher odds of undergoing mammography.

CONCLUSIONS

Although recent ASCO guidelines recommend surveillance mammography after lumpectomy, a minority of MaBC survivors undergo surveillance mammography, even after lumpectomy. This is likely due to the paucity of data regarding the true benefits and harms of surveillance/screening mammography for MaBC.

Comparison of a modified staging system with 8th edition AJCC criteria in a North American cohort of pT2/pT3 HPV-negative penile squamous cell carcinoma

The staging for pT2/pT3 penile squamous cell carcinoma (pSCC) has undergone major changes. Some authors proposed criteria wherein the distinction between pT2/pT3 was made using the same histopathological variables that are currently utilized to differentiate pT1a/pT1b. In this single-institution, North American study, we focused on (HPV-negative) pT2/3 pSCCs (i.e., tumors invading corpus spongiosum/corpus cavernosum), and compared the prognostic ability of the following systems: (i) AJCC (8th edition) criteria; (ii) modified staging criteria proposed by Sali et al. (Am J Surg Pathol. 2020; 44:1112-7). In the proposed system, pT2 tumors were defined as those devoid of lymphovascular invasion (LVI) or perineural invasion (PNI), and were not poorly differentiated; whereas pT3 showed one or more of the following: LVI, PNI, and/or grade 3. 48 pT2/pT3 cases were included (AJCC, pT2: 27 and pT3: 21; Proposed, pT2: 22 and pT3: 26). The disease-free survival (DFS) and progression-free survival (PFS) did not differ between pT2 and pT3, following the current AJCC definitions (p = 0.19 and p = 0.10, respectively). When the pT2/3 stages were reconstructed using the modified criteria, however, a statistically significant difference was present in both DFS and PFS between pT2 and pT3 (p = 0.004 and p = 0.003, respectively). The proposed staging system has the potential to improve the prognostication of pT2/pT3 tumors in pSCC. Each of these histopathologic variables has been shown to have a significant association with outcomes in pSCC, which is an advantage. Further studies are needed to demonstrate the utility of this modified staging system in patient populations from other geographic regions.

Feasibility analysis of pathology and genetic yield from a prospective trial of tissue biopsies in metastatic castrate-resistant prostate cancer (mCRPC)

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Background: Evaluating tumor specific pathologic and genetic profiles in mCRPC stage is difficult due to the limited availability of mCRPC tissue. We describe findings from a prospective cohort study performed to obtain concomitant histopathology and genetic information in mCRPC. Methods: Patients with mCRPC initiating abiraterone acetate therapy underwent 2 serial (3 months apart) metastatic (met) site needle core biopsies (NCB1/2). Bone lesions were biopsied using 11-13G core needles and 18G core biopsy devices were used for non-osseous masses. Up to 4 cores were obtained at each biopsy with the 1st core (S1) sent for DNA sequencing, the 2nd (S2) for RNA sequencing, and the 3rd/4th (X3, X4) submitted for xenograft implantation. From each, 1-2 mm segments were separated and formalin-fixed for histopathologic examination (HPE). Results: A total of 54 patients, enrolled between June 2013 and July 2014, underwent 94 NCB (54 NCB1, 40 NCB2), rendering a total of 259 samples (94 S1; 75 S2; 59 X3 and 31 X4) of which 85 (32%) were positive (pos) for tumor by HPE. Positivity for tumor in S1, S2, X3, and X4 cores was 42%, 33%, 22%, and 19%, respectively. At least one core pos for met tumor was observed in 62% NCB1 and 52% NCB2 (overall 52/94; 56%). Met sites biopsied include bone (71), lymph nodes (18), liver (3), penile (1) and pelvic (1) soft tissues. HPE revealed met adenocarcinoma in 44/52, and poorly differentiated carcinoma in 8/52. Gleason grade applied to the met ranged from 3+4 to 5+5. 45/85 pos samples (53%) had > 50% tumor cellularity. Pos NCB in bone lesions was observed in 23/71 (32%), compared to 17/23 (73%) of non-bone sites (p=.0004). 85 S1 samples yielded DNA material, of which 66 (77%) had ≥10% tumoral DNA. 24 cases with negative HPE had ≥10% tumoral DNA; 7 cases with pos HPE had <10 tumoral DNA. In all, 76/94 (81%) NCB yielded tumor material either by HPE or DNA analysis. Conclusions: NCB of mCRPC is feasible and provides adequate tissue for pursuing HPE and sequencing studies. HPE of extracted material correlates with DNA sequencing data and provides complementary information on tumor features. Bone lesions yield significantly less tumoral material than non-osseous sites.

Identification of amyloidosis of the urinary tract and prostate: Opportunities for early diagnosis & intervention in systemic disease

OBJECTIVES

To determine the prevalence of different amyloid types and frequency of associated systemic amyloidosis in the urinary tract/prostate.

METHODS

We studied Congo red-positive prostate (n = 150) and urinary tract (n = 767) specimens typed by a proteomics-based method between 2008 and 2020. Clinical follow up was available for a subset (urinary tract, n = 111; prostate, n = 17). Amyloid types were correlated with various clinicopathologic features. For patients with clinical follow up, chart review was performed to establish localized versus systemic disease, frequency of initial diagnosis of amyloidosis on urinary tract/prostate specimens, presence of cardiac disease, and death from disease-related complications.

RESULTS

The most common amyloid types were AL/AH in urinary tract (479/767, 62 %) and localized ASem1 in prostate (64/150, 43 %). Urinary tract AL/AH amyloid was usually localized, but systemic AL amyloidosis occurred in both sites (urinary tract: 5/71, 7 %; prostate: 2/2, 100 %). ATTR amyloidosis was seen in over a third of cases (urinary tract: 286/767, 37 %; prostate: 55/150, 37 %). Urinary tract/prostate was the site of the initial ATTR amyloidosis diagnosis in 44/48 patients (92 %), and 38/48 (79 %) were subsequently found to have cardiac involvement. Seminal vesicle/ejaculatory duct involvement was pathognomonic for ASem1-type amyloidosis (39/39, 100 %).

CONCLUSIONS

Over 40 % of patients had systemic amyloidosis, with urinary tract/prostate often the first site in which amyloid was identified. Since early recognition of systemic amyloidosis is critical for optimal patient outcomes, there should be a low threshold to perform Congo red stain. Proteomics-based amyloid typing is recommended since treatment depends on correctly identifying the amyloid type.

Genomic attributes of prostate cancer across primary and metastatic noncastrate and castrate resistant disease states: a next generation sequencing study of 183 patients

Primary prostatic adenocarcinoma (pPC) undergoes genomic evolution secondary to therapy-related selection pressures as it transitions to metastatic noncastrate (mNC-PC) and castrate resistant (mCR-PC) disease. Next generation sequencing results were evaluated for pPC (n = 97), locally advanced disease (involving urinary bladder/rectum, n = 12), mNC-PC (n = 21), and mCR-PC (n = 54). We identified enrichment of TP53 alterations in high-grade pPC, TP53/RB1 alterations in HGNE disease, and AR alterations in metastatic and castrate resistant disease. Actionable alterations (MSI-H phenotype and HRR genes) were identified in approximately a fifth of all cases. These results help elucidate the landscape of genomic alterations across the clinical spectrum of prostate cancer.

Mass Spectrometry-Based Assessment of Prostate Cancer-Associated Crystalloids Reveals Enrichment for Growth & Differentiation Factor 15 (GDF15)

Intraluminal crystalloids are a common finding within malignant prostatic acini and are infrequently identified within benign glands. The proteomic composition of these crystalloids remains poorly understood and may provide insight regarding prostate cancer pathogenesis. Laser microdissection assisted liquid chromatography tandem mass spectrometry (LMD-LC-MS/MS) was performed to compare proteomic composition of corpora amylacea within benign acini (n=9), prostatic adenocarcinoma-associated crystalloids (n=8), benign (n=8), and malignant prostatic acini (n=6). The expression of candidate biomarkers was then measured in urine specimens from patients with (n=8) and without prostate cancer (n=10) using ELISA; and immunohistochemistry-based expression in adjacent prostate cancer and benign glands was assessed in 56 whole-slide sections from radical prostatectomy specimens. LMD-LC-MS/MS revealed enrichment for the C-terminal portion of growth and differentiation factor 15 (GDF15) in prostatic crystalloids. Although urinary GDF15 levels were higher in patients with prostatic adenocarcinoma compared to those without (median: 1561.2 vs 1101.3, arbitrary units), this did not meet statistical significance (p=0.07). Immunohistochemistry for GDF15 revealed occasional positivity in benign glands (median H-score: 30, n=56), and diffuse positivity in prostatic adenocarcinoma (median H-score: 200, n=56, p<0.0001). No significant difference was identified within different prognostic grade groups of prostatic adenocarcinoma, or within malignant glands with large cribriform morphology. Our results show that the C-terminal portion of GDF15 is enriched in prostate cancer-associated crystalloids, and higher GDF15 expression is seen in malignant rather than benign prostatic acini. Improved understanding of the proteomic composition of prostate cancer-associated crystalloids provides the rationale for evaluating GDF15 as a urine-based biomarker of prostate cancer.

Abstract A05: Developing patient derived xenograft (PDX) models for metastatic castration resistant prostate cancer (CRPC) during CYP17 inhibitor therapy

Castration resistant prostate cancer (CRPC) is a deadly disease with a poor prognosis. Treatment options for CRPC patients involve taxanes or newly developed drugs targeting the androgen pathway or androgen synthesis, including CYP17 inhibitors. However, response to therapy varies dramatically among patients, which might be due, in part, to tumor heterogeneity. Therefore, understanding of the genomic landscape of CRPC would be important to help achieve better outcomes by developing personalized therapies. One challenge contributing to our lack of therapies for CRPC is a paucity of clinically relevant animal models predictive of response to therapy in human patients. The Prostate Cancer Medically Optimized Genome Enhanced Therapy (PROMOTE) study is a Mayo Clinic prospective trial designed for patients with metastatic CRPC who are treated with abiraterone acetate, a CYP17 inhibitor, over a 12 week period. Fresh tissue from metastatic lesions, primarily bone metastases, was obtained by needle core biopsy before and 12 weeks after initiating abiraterone acetate treatment. The samples were submitted for DNA and RNA sequencing and were also used to generate patient-derived xenograft (PDX) models. PDX models were developed by injecting biopsy samples subcutaneously or under the renal capsule in male non-obese diabetic (NOD)/severe combined immunodeficient (SCID) or NOD/SCID/IL-2γ-receptor null (NSG) mice implanted with 25mg testosterone pellets at the time of tissue implantation and 2 months later. Baseline samples from 103 unique patients as well as second samples from 61 patients post abiraterone acetate treatment were injected into approximately 600 mice. Of the samples for which pathology is currently available, 31% of the biopsies injected into mice were confirmed to include tumor tissue, which may be compared with a figure of 37.5% of samples sent for sequencing. Thus far, we have established 8 PDX models, four from baseline and four from post treatment samples. Seven models were derived from metastatic bone lesions, and one model from a liver metastasis. The tumor tissue in each model was expanded into a second of generation of mice and harvested when the tumors grew. No tumor was expanded more than four times. Genomic and transcriptomic analysis of xenograft tissue from different “generations” of xenograft expansion is ongoing and will be compared with similar data for the original biopsy. The evaluation of treatment response after exposure of these PDX models to different therapies including CYP19 inhibitors, AR blockers and taxanes is ongoing. These PDX models provide a tool for future drug testing and for studying mechanisms of resistance to therapy in CRPC.

Citation Format: Fang Xie, Manish Kohli, Yin Ping, Rafael E. Jimenez, Richard M. Weinshilboum, Liewei Wang. Developing patient derived xenograft (PDX) models for metastatic castration resistant prostate cancer (CRPC) during CYP17 inhibitor therapy. [abstract]. In: Proceedings of the AACR Special Conference: Patient-Derived Cancer Models: Present and Future Applications from Basic Science to the Clinic; Feb 11-14, 2016; New Orleans, LA. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(16_Suppl):Abstract nr A05.

Abstract 3304: Role of Vascular Endothelial Growth Factor C in promoting radioresistance of prostate cancer

Radiotherapy is an important treatment regimen for prostate cancer. We have shown that the lymphangiogenic growth factor, Vascular Endothelial Growth Factor C (VEGF-C), induces docetaxel resistance and autophagy in prostate cancer (Muders et al., Cancer Res 2009 and Stanton et al., Cancer Res 2013). In this study we have evaluated the role of VEGF-C and VEGF-C induced autophagy in radioresistance of prostate cancer using cell culture experiments and human tissue samples.

The human prostate carcinoma cell lines PC-3, LNCaP and DU145 were used in these cell culture experiments. Clonogenic survival of prostate cancer cells, after RNA interference (RNAi) of VEGF-C, autophagy related gene 5 (ATG5), and after addition of recombinant human VEGF-C following irradiation therapy, was evaluated. Autophagic flux was tested after ionizing irradiation using a Light-Chain-3 II immunoblot. To confirm our in vitro findings, human tissues of patients who underwent radical prostatectomy and adjuvant radiotherapy at Mayo Clinic were evaluated for VEGF-C expression. The quantity and intensity of VEGF-C staining was evaluated by two pathologists independently and correlated with biochemical relapse free survival (BRFS). The follow-up time is up to 23 years after radiotherapy. Multivariate Cox analysis was performed.

VEGF-C levels correlated with a significantly higher radioresistance in colony formation assays and human tissue samples by multivariate analysis. The risk of biochemical recurrence increased 2.8 fold (95% confidence interval: 1.109 to 7.237; p = 0.03) when VEGF-C was highly expressed in prostatectomy patients with adjuvant radiotherapy. In line with our studies on autophagy in VEGF-C mediated docetaxel resistance of prostate cancer, autophagic flux was reduced after VEGF-C depletion during radiation. Interestingly, RNAi for ATG5 showed no effect on radiosensitivity which suggests that the decrease in autophagic flux after VEGF-C depletion is not responsible for the increased radiosensitivity.

We conclude that VEGF-C is an important mediator of radiotherapy resistance in prostate cancer. In contrast to our published results on chemotherapy resistance, VEGF-C induced autophagy appears to be less important for resistance against ionizing radiation. Other VEGF-C dependent mechanisms for therapy resistance are under investigation.

Citation Format: Steffi Haberlau, Pia Hönscheid, Rafael E. Jimenez, Gustavo B. Baretton, Donald J. Tindall, Mechthild Krause, Kaustubh Datta, Michael H. Muders. Role of Vascular Endothelial Growth Factor C in promoting radioresistance of prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3304. doi:10.1158/1538-7445.AM2015-3304

Molecular and Immunophenotypic Correlates of Metastatic Epithelioid Angiomyolipoma Include Alterations of TP53, RB1, and ATRX

Context.—

Epithelioid angiomyolipomas (eAMLs) are rare tumors of the kidney that occur in patients with tuberous sclerosis complex or in a sporadic setting; a subset of these tumors exhibit metastatic behavior.

Objective.—

To analyze molecular profiling data to identify pathogenic alterations in rare cases of metastatic eAML, and to identify immunohistochemistry (IHC)-based surrogate markers.

Design.—

Molecular profiling data from the American Association for Cancer Research GENIE registry was accessed for 23 patients with angiomyolipomas, and 9 of 16 patients with eAMLs in our institutional registry were evaluated with next-generation sequencing. IHC was performed to screen for alterations of P53, RB, and ATRX for all 16 institutional cases.

Results.—

Combined alterations of 5 tumor-suppressor genes (TP53, ATRX, RB1, APC, and NF1) were identified using next-generation sequencing in 7 of 8 (88%) patients with metastatic disease compared to a single patient with nonmetastatic disease (RB1 variant of uncertain significance; 1 of 24, 4%). No cases with abnormal IHC results were identified in 11 patients with nonmetastatic disease compared to 3 of 5 patients with metastatic disease.

Conclusions.—

Our results show that the majority of metastatic eAMLs have mutations of 5 tumor-suppressor genes (TP53, ATRX, RB1, APC, and NF1), while these are rare in patients with nonmetastatic disease. Furthermore, IHC for P53, RB, and ATRX may serve as a screen for a subset of these alterations in resource-limited settings. These findings, if validated in larger data sets, have the potential to predict metastatic behavior in eAML.

Androgen receptor (AR) based biomarker association with response to abiraterone acetate/prednisone (AA/P) in metastatic castrate resistant prostate cancer (mCRPC)

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Background: AA/P is an FDA approved treatment for mCRPC. Since markers of early resistance to AA/P are unknown, we report initial findings of androgen receptor (AR) based associations with short term (12 week) progression on AA/P. Methods: mCRPC stage patients (pts) initiating pre-chemotherapy AA/P underwent metastatic site biopsies at baseline (pre AA/P) and after 12 weeks. Baseline somatic whole exome DNA, tumor gene expression for AR full length (ARFL), AR splice variant 7 (ARV7) and ARV7/ARFL ratios were compared in progessors versus non-progressors. Progression at or within 12 weeks of AA/P therapy was defined as death or disease progression by PCWG2 “composite progression (CP)” and/or “radiographic progression” endpoints. Wilcoxon rank-sum tests were used to test for differences in the two groups for comparing ARFL, ARV7 expressions and ARV7/ARFL ratios and chi square tests were used for differences in copy number variation. Results: Between 1/2013 and 6/2014, 59 pts were enrolled of which 44 have disease assessment data at the12-week time point. CP was observed in 17/44 patients. DNA seq and clinical data was available for 42/44 pts. Using radiographic progression at 12 weeks, AR Amplification/Gain was observed in 20/26 non-progressors (13 with Amplification) and in 9/16 progressors (P-value = 0.19; OR 2.5). ARFL and ARV7 gene expressions in both groups is provided in table. Conclusions: A trend towards higher ARV7/ARFL gene expression ratio in metastases was observed with early progression on AA/P. AR gain/amplification is observed less often in pts with early progression. Validation of these findings is on-going in this prospective trial. Clinical trial information: NCT# 01953640. [Table: see text]

The Tsar's doctor: The selfless and devoted life of Dr Eugene Botkin

Eugene Botkin was Nicholas II's court physician from 1908 until the abolition of the monarchy. He accompanied the royal family into exile and shared their fate at Ekaterinburg in 1918. The son of a prominent St. Petersburg physician, he trained at the Universities of St. Petersburg, Berlin, and Heidelberg. As court physician, he participated in the management of the Tsarevich Alexei's hemophilia, but most of his time was spent taking care of the Tsarina's multiple psychosomatic ailments. A deep sense of duty, rendered him unable to part from the royal family during the difficult months of exile and imprisonment. During this period there were several episodes of imminent threat to his life, where despite having the opportunity to leave, he voluntarily decided to stay with the Romanovs. In up to three occasions he said his goodbyes to his children, only to find out the next day that the threat had been contained. Ironically, the last time he spoke to them he did not think they would be separated for long. In this study, we will analyze his life, in particular the events of his last days, and will explore the reasoning behind his selfless actions.

Abstract 4518: Targeting SIAH2 E3 ligase to inhibit HER2/EGFR/RAS activation and to block tumorigenesis and metastasis of highly invasive human breast cancer cells

Breast cancer is the most common form of cancer diagnosed and the second leading cause of cancer death among women in the United States. Cancer metastases are the major cause of morbidity and mortality among breast cancer patients. The central importance of the HER2/Neu/EGFR/RAS signaling pathway has been well established in the growth, invasion and metastasis of human breast cancer, even though oncogenic RAS mutations are rare in breast cancer, activation of the tumor-promoting ERBB/RAS pathway has been consistently documented in high-grade breast tumors. As such, novel approaches to inhibit activated ERBB/RAS signals constitute important measures to block tumor growth and metastasis in mammary tumors. In this study, instead of targeting an upstream signaling component such as HER2/EGFR/RAS, we targeted the most downstream signaling module identified in the RAS pathway - the SIAH proteolytic machinery. SIAH is an evolutionarily conserved RING E3 ligase that is a critical “gatekeeper” required for RAS signal transduction in human cancer cells. SIAH is specifically expressed in tumor cells in 120 human breast cancer patients examined so far. The increased SIAH expression is correlated with increased grades and aggressiveness of human breast cancer. We then asked whether inhibiting the gatekeeper function of SIAH would be effective in blocking mammary tumorigenesis and metastasis in human breast cancer. Our results indicated that SIAH2-deficiency successfully abolished tumor growth of three breast cancer cell lines (MDA-MB-231, MDA-MB-435 and MDA-MB-468) in soft agar assays as well as in athymic nude mice. Importantly, by inhibiting SIAH2 function in highly aggressive human breast cancer cells, we are able to completely block tumorigenesis and metastasis of two highly invasive and metastatic human breast cancer cell lines (MDA-MB-231 and MDA-MB-435). These findings suggest that SIAH2 may be an attractive new therapeutic target for novel breast cancer therapy and developing anti-SIAH molecules will aid in expanding our arsenal of effective anticancer therapies. More effective breast cancer treatments may be obtained by multi-pronged synergistic inhibitions at upstream (HER2/EGFR membrane receptors), midstream (RAS/RAF/MEK/mTOR) and downstream (SIAH E3 ligase) signaling modules in the HER2/EGFR/RAS pathway in parallel. Thus, by attacking the growth-promoting ERBB/RAS pathway at multiple signaling modules simultaneously, we may be in a great position to halt the genesis, progression and metastasis of human breast cancer. If successful, this study has the promise to be translated to the cancer clinics to alleviate tumor burdens, inhibit cancer metastasis, improve the efficacy for the treatment of breast cancer, and in particularly help cancer patients with metastatic diseases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4518.

Penile squamous cell carcinoma exclusive to the shaft, with a proposal for a novel staging system

Penile squamous cell carcinomas (SCC) originating in the shaft are rare. pT1/pT2 categories in the American Joint Committee on Cancer (AJCC) staging manual (8th edition) are poorly defined for SCCs arising in the dorsal shaft as anatomic structures differ between the glans and dorsal shaft (corpus spongiosum vs dartos/Buck's fascia, respectively). We reviewed six penile SCC cases exclusive to the shaft, an unusual presentation, identified amongst 120 patients treated with penectomy. We propose a novel pT staging system for dorsal shaft tumors tailored to its anatomic landmarks, where tumors extending to Buck's fascia are considered pT2 instead of pT1. The mean age at penectomy, average duration of follow-up, and mean depth of invasion were 64 years, 45 months, and 9.8 mm, respectively. Four cases were moderately differentiated, HPV-negative SCCs of the usual type and two cases were HPV-positive basaloid and warty-basaloid carcinomas. Three cases had nodal or distant metastasis at the time of penectomy, and histologic assessment in these cases showed invasion into the Buck's fascia or deeper. According to the current AJCC system, only one of these three cases would be staged as ≥ pT2. In contrast, all three metastatic tumors would be staged as ≥ pT2 in the proposed model. At last follow-up, one patient died of disease-related complications. Based on this limited series, the proposed staging model appears to suggest better patient stratification for pT1/pT2 stages. This model incorporates Buck's fascia, which has been postulated as a pathway of tumor infiltration. Additional studies are needed to validate this model.

Proteomic and Clinicopathologic Assessment of Penile Amyloidosis: A Single Institutional Review of 12 Cases

OBJECTIVES

There is a paucity of data on penile amyloidosis. We aimed to assess the frequency of different amyloid types in surgical specimens from the penis involved by amyloidosis and correlate relevant clinicopathologic parameters with proteomic findings.

METHODS

Since 2008, our reference laboratory has performed liquid chromatography/tandem mass spectrometry (LC-MS/MS) for amyloid typing. The institutional pathology archive and reference laboratory database were queried to retrospectively identify all penile surgical pathology specimens with LC-MS/MS results between January 1, 2008, and November 23, 2022. Archived H&E-stained and Congo red-stained sections were re-reviewed.

RESULTS

Twelve cases of penile amyloidosis were identified, which represented 0.35% (n = 3,456) of penile surgical specimens. AL-type amyloid was most frequent (n = 7), followed by keratin-type amyloid (n = 3) and ATTR (transthyretin)-type amyloid (n = 2). AL-type amyloid cases often showed diffuse dermal/lamina propria deposition, whereas all keratin-type amyloid cases were localized to the superficial dermis. Two cases with keratin-type amyloid had concomitant cutaneous findings (penile intraepithelial neoplasia and condyloma).

CONCLUSIONS

This series, the largest to date, demonstrates that penile amyloidosis has a heterogeneous proteomic landscape. To the best of our knowledge, this is the first study describing ATTR (transthyretin)-type penile amyloid.

Single nucleotide polymorphism (SNP) chromosomal microarray as a diagnostic tool for mucinous tubular and spindle cell carcinoma: A validation study

Mucinous tubular and spindle cell carcinoma (MTSCC) shows significant overlap with papillary renal cell carcinoma (PRCC), and harbor recurrent copy-number alterations (CNA). We evaluated 16 RCC with features suggestive of MTSCC using chromosomal microarrays. The cohort was comprised of 8 females and males, each, with an age range of 33-79 years (median, 59), and a tumor size range of 3.4-15.5 cm (median, 5.0). Half the tumors were high-grade (8/16, 50%) with features such as necrosis, marked cytologic atypia, and sarcomatoid differentiation, and 5/16 (31%) were high stage (≥pT3a). Three (of 16, 19%) cases had a predominant (>95%) spindle cell component, whereas 5/16 (31%) were composed of a predominant (>95%) epithelial component. Most cases (12/16, 75%) exhibited a myxoid background and/or extravasated mucin, at least focally. Twelve (of 16, 75%) cases demonstrated CNA diagnostic of MTSCC (losses of chromosomes 1, 4, 6, 8, 9, 13, 14, 15, and 22). In addition, 2 high-grade tumors showed loss of CDKN2A/B, and gain of 1q, respectively, both of which are associated with aggressive behavior. Three (of 16, 19%) cases, demonstrated nonspecific CNA, and did not meet diagnostic criteria for established RCC subtypes. One (of 16, 6%) low-grade epithelial predominant tumor (biopsy) demonstrated characteristic gains of 7, 17, and loss of Y, diagnostic of PRCC. MTSCC can be a morphologically heterogenous tumor. Our study validates the detection of characteristic chromosomal CNA for diagnostic use that may be useful in challenging cases with unusual spindle cell or epithelial predominant features, as well as in high-grade tumors.

Abstract P6-15-14: Inhibit SIAH E3 Ligase, a Downstream Signaling Module Required for the HER2/EGFR/RAS Signal Transduction, To Block Tumorigenesis and Metastasis of Highly Invasive Human Breast Cancers

The central importance of the HER2/Neu/EGFR/RAS signaling pathway has been well established in the growth, invasion and metastasis of human breast cancer, even though oncogenic RAS mutations are rare in breast cancer, activation of the tumor-promoting ERBB/RAS/MEK/MAPK pathway has been consistently documented in high-grade breast tumors. As such, novel approaches to inhibit activated ERBB/RAS signals constitute important measures to block tumor growth and metastasis in mammary tumors. In this study, instead of targeting an upstream signaling component such as HER2/EGFR/RAS, we targeted the most downstream signaling module identified in the RAS pathway — the SIAH proteolytic machinery. SIAH is an evolutionarily conserved RING E3 ligase that is a critical “gatekeeper” required for RAS signal transduction in human cancer cells. SIAH is specifically expressed in tumor cells in 120 human breast cancer patients examined so far. The increased SIAH expression is correlated with increased grades and aggressiveness of human breast cancer. We then asked whether inhibiting the gatekeeper function of SIAH would be effective in blocking mammary tumorigenesis and metastasis in human breast cancer. Our results indicated that SIAH2-deficiency successfully abolished tumor growth of three breast cancer cell lines (MDA-MB-231, MDA-MB-435 and MDA-MB-468) in soft agar assays as well as in athymic nude mice. Importantly, by inhibiting SIAH2 function in highly aggressive human breast cancer cells, we are able to completely block tumorigenesis and metastasis of two highly invasive and metastatic human breast cancer cell lines (MDA-MB-231 and MDA-MB-435). These findings suggest that SIAH2 may be an attractive new therapeutic target for novel breast cancer therapy and developing anti-SIAH molecules will aid in expanding our arsenal of effective anticancer therapies. More effective breast cancer treatments may be obtained by multi-pronged synergistic inhibitions at upstream (HER2/EGFR membrane receptors), midstream (RAS/RAF/MEK/mTOR) and downstream (SIAH E3 ligase) signaling modules in the HER2/EGFR/RAS pathway in parallel. Thus, by attacking the growth-promoting ERBB/RAS pathway at multiple signaling modules simultaneously, we may be in a great position to halt the genesis, progression and metastasis of human breast cancer.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-15-14.

Abstract P4-17-08: Surveillance mammography after treatment for male breast cancer

Background: The clinical utility of routine annual mammogram after curative-intent treatment for male breast cancer is uncertain. There is potentially greater value after lumpectomy (as surveillance for ipsilateral recurrence) than mastectomy (as screening for a new contralateral cancer). The goal of this study was to assess real world use of mammography in men during the first year after lumpectomy or mastectomy to treat breast cancer.

Methods: Administrative claims data from OptumLabs Data Warehouse (a large US database that includes privately insured patients and Medicare Advantage-insured enrollees from all 50 states and of all ages and ethnic and racial groups) were used to identify men treated with breast surgery for a new diagnosis of breast cancer between 2007 and 2017. We required continuous coverage starting at least 6 months prior to the non-metastatic breast cancer diagnosis and continuing until at least 13 months after the breast surgery. Our primary endpoint was the proportion of patients who had at least one mammogram during the year (13-month period, to allow for scheduling and other logistical delays) after lumpectomy or mastectomy. Univariate and multivariate testing were performed to identify predictors of mammography (with p&lt;0.05 used as the threshold for statistical significance for both). Our secondary endpoint was the proportion with at least one mammogram within 24 months of surgery, performed in a subset who maintained their insurance coverage for at least that duration.

Results: The 13-month analysis included 730 men with a median age at diagnosis of 62 years (Range: 25 to 87 years) and a median follow-up duration of 35 months (Range: 13 to 134 months). 209 (29%) of these men underwent mammography within 13 months after surgery. The characteristics of patients who underwent mammography and those who did not are shown in Table 1. Mammography was more likely after lumpectomy than mastectomy (41% vs. 27%) and after radiation therapy (41% vs. 32% in those who did not receive radiation). In a multivariate logistic regression model, more recent diagnosis (2015+) was associated with lower odds of undergoing mammography, while receipt of radiation was associated with higher odds of undergoing mammography. In the subset of patients with two or more years of post-surgery coverage (n=527), the proportion who had at least one mammogram during that 24-month period was 49% after lumpectomy and 40% after mastectomy.

Conclusions: In this insured cohort, 73% of men did not undergo mammography within a year after mastectomy, and 59% did not within a year after lumpectomy. Mammography was less likely in patients diagnosed more recently (perhaps due to acknowledgment of the unique aspects of male breast cancer including a relatively low risk of contralateral second primary tumors), and more likely in those who received radiation. These variations in practice likely result from the paucity of evidence-based guidelines for male breast cancer survivorship care. More research is needed pertaining to whether or not mammograms improve clinical outcomes after curative intent treatment for male breast cancer.

Table 1: Patient characteristics associated with receipt of mammogram within first 13 months after male breast cancer surgeryUnivariate AnalysisMultivariate AnalysisNo Mammogram (N=521)Mammogram (N=209)P-value, chi-square testOdds Ratio (OR) and 95% CIP-value for ORAge Group:0.1225-4966 (12.7%)32 (15.3%)Reference50-64216 (41.5%)98 (46.9%)0.99 (0.60, 1.63)0.9665-74112 (21.5%)44 (21.1%)0.87 (0.48, 1.57)0.6575+127 (24.4%)35 (16.7%)0.57 (0.30, 1.07)0.08Census Region:0.52Midwest138 (26.5%)59 (28.2%)ReferenceNortheast97 (18.6%)47 (22.5%)1.10 (0.68, 1.78)0.69South223 (42.8%)79 (37.8%)0.74 (0.49, 1.11)0.15West63 (12.1%)24 (11.5%)0.83 (0.47, 1.47)0.51Year of diagnosis:0.072007-2010126 (24.2%)65 (31.1%)Reference2011-2014199 (38.2%)82 (39.2%)0.80 (0.54, 1.20)0.292015+196 (37.6%)62 (29.7%)0.63 (0.41, 0.96)0.03Elixhauser Category:0.250148 (28.4%)69 (33.0%)Reference1-2218 (41.8%)74 (35.4%)0.85 (0.56, 1.28)0.433+155 (29.8%)66 (31.6%)1.18 (0.75, 1.87)0.47Surgery Type:0.005Lumpectomy55 (10.6%)38 (18.2%)ReferenceMastectomy466 (89.4%)171 (81.8%)1.57 (0.97, 2.55)0.07Chemotherapy:0.79No301 (57.8%)123 (58.9%)ReferenceYes220 (42.2%)86 (41.1%)0.79 (0.54, 1.16)0.23Radiation:0.02No355 (68.1%)124 (59.3%)ReferenceYes166 (31.9%)85 (40.7%)1.51 (1.03, 2.20)0.03

Citation Format: Siddhartha Yadav, Lindsey Sangaralingham, Stephanie R. Payne, Karthik V. Giridhar, Tina J. Hieken, Judy C. Boughey, Robert W. Mutter, John R. Hawse, Rafael E. Jimenez, Rachel A. Freedman, Sadia Choudhery, Fergus J. Couch, Celine M. Vachon, Nilay Shah, Roberto A. Leon-Ferre, Kathryn J. Ruddy. Surveillance mammography after treatment for male breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-17-08.

"A monument to suffering and to patience": The harrowing journey of Nabby Adams through breast cancer

In 1813, Abigail "Nabby" Adams, the daughter of the second president of the United States, John Adams (1797-1801), passed away from metastatic breast cancer. Her ordeal began in 1810, at age 44, when she discovered a lump in her right breast She consulted with Dr Benjamin Rush, one of the most prominent physicians of the time and a signer of the Declaration of Independence, which resulted in a recommendation for an immediate mastectomy. The surgery was performed at her parent's home in Quincy, Massachusetts, by Dr John Warren. The crude and painful nature of the surgical procedure was highly traumatic to Ms. Adams and her family. After a few months, she returned to her home in rural New York. Within a few months she began feeling generalized pain. When it was evident that her symptoms were the result of disseminated breast cancer, she returned to her parents' house, where she died on August 15, a mere 22 months after her surgery. Ms. Adams' suffering through the stark treatment was the result of a unique historical period, when the medical community had just recently dismissed Galen's paradigms, but still lacked a basic knowledge of the disease's nature or the ability to administer painless, safe surgical treatment.

High-risk human papilloma virus status & outcomes for penile squamous cell carcinoma: A single institution experience

OBJECTIVES

There is a paucity of data on North American cohorts of patients with penile squamous cell carcinoma (pSCC). Herein, we aimed to assess the sensitivity of various modalities to identify human papillomavirus (HPV) status, determine the prevalence of high-risk HPV-positivity, and evaluate the prognostic impact of relevant clinicopathologic variables.

METHODS

Patients with pSCC (n = 121) consecutively treated with partial/total penectomy (2000-2022) at a single institution were included. HPV status (based on immunohistochemistry [IHC], in situ hybridization [ISH], and panviral metagenomic sequencing [PMS]), histologic features, and outcomes were reviewed. Outcome events included death due to disease and progression.

RESULTS

The majority of patients were white (105/121, 86.8%). Thirty-seven (30.6%) were high-risk HPV-positive, and morphologic evaluation had a sensitivity of 97.3% (95% confidence interval [CI], 86.2-99.5) for predicting high-risk HPV status compared to IHC/ISH/PMS. Disease progression was more common among high-risk HPV-negative compared to high-risk HPV-positive patients (HR 2.74, CI 1.12-8.23, P = 0.03). Moreover, among high-risk HPV-negative patients, those with moderate-poorly differentiated tumors had increased disease-specific mortality (32.6%, CI 17.1-48.1) compared to those with well-differentiated tumors (0%). Among high-risk HPV-positive patients, those with basaloid morphology had lower disease-specific mortality (0% vs 14.4%, CI 0.0-33.1).

CONCLUSIONS

We demonstrate high-risk HPV-positivity in approximately one-third of patients with pSCC. Morphologic evaluation alone had a high sensitivity in correctly determining HPV status. Our results suggest that high-risk HPV status and morphologic features (differentiation in high-risk HPV-negative, and basaloid subtype in high-risk HPV-positive pSCC) may have prognostic value.