Overexpression of CD73 is associated with recurrence and poor prognosis of gingivobuccal oral cancer as revealed by transcriptome and deep immune profiling of paired tumor and margin tissues

BACKGROUND

For various cancers, differences in response to treatment and subsequent survival period have been reported to be associated with variation in immune contextures.

AIM

We sought to identify whether such association exists in respect of gingivobuccal oral cancer.

MATERIALS AND METHODS

We performed deep immune profiling of tumor and margin tissues collected from 46 treatment naïve, Human Papillomavirus (HPV) negative, patients. Each patient was followed for 24 months and prognosis (recurrence/death) noted. Key findings were validated by comparing with TCGA-HNSC cohort data.

RESULTS

About 28% of patients showed poor post-treatment prognosis. These patients exhibited a high probability of recurrence even within 1 year and death within 2 years. There was restricted immune cell infiltration in tumor, but not in margin, among these patients. Reduced expression of eight immune-related genes (IRGs) (NT5E, THRA, RBP1, TLR4, ITGA6, BMPR1B, ITGAV, SSTR1) in tumor strongly predicted better quality of prognosis, both in our patient cohort and in TCGA-HNSC cohort. Tumors of patients with better prognosis were associated with (a) lower CD73+ cells with concomitant lower expression level of NT5E/CD73, (b) higher proportions of CD4+ and CD8+ T cells, B cells, NK cells, M1 macrophages, (c) higher %Granzyme+ cells, (d) higher TCR and BCR repertoire diversities. CD73 expression in tumor was associated with low CD8+ and CD4+ T cells, low immune repertoire diversity, and advanced cancer stage.

DISCUSSION AND CONCLUSION

High infiltration of anti-tumor immune cells in both tumors and margins results in good prognosis, while in patients with minimal infiltration in tumors in spite of high infiltration in margins results in poor prognosis. Targeted CD73 immune-checkpoint inhibition may improve clinical outcome.

Detection of Axillary Lymph Node Involvement in Early-Stage Breast Cancer: Comparison between Staging 18F-2-Fluoro-2-Deoxy-D-Glucose Positron Emission Tomography-Computed Tomography Scans, Mammography, and Sentinel Lymph Node Biopsy

Aims

The aim of this study was to evaluate the role of 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) scan in the detection of axillary lymph node (ALN) involvement and comparison with sentinel lymph node biopsy (SLNB) in operable early-stage breast cancer (EBC).

Settings and Design

It is a retrospective analysis of staging PET-CT scan of EBC.

Methods

A total of 128 patients with histopathologically proven breast cancer (BC) were included in the study. Preoperative mammography supplemented with ultrasonography and staging 18F-FDG PET-CT scan was done for all patients. Surgery was done within 30 (mean ± standard deviation = 13.8 ± 10.5) days of staging. SLNB was performed in patients without PET-positive ALNs. All patients with positive sentinel nodes and PET-positive ALNs underwent axillary lymph node dissection (ALND).

Statistical Analysis Used

The comparison between categorical variables was made by Chi-square/Fisher's exact test as applicable. For continuous variables comparisons, Student's t-test and one-way analysis of variance tests were used.

Results

Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of PET-CT scan for detection of ALN involvement were 41.7%, 93.2%, 92.1%, and 45.6%, respectively. Sensitivity, specificity, PPV, and NPV of mammography were 84.5%, 54.5%, 78.0%, and 68.6%, respectively. Sixteen out of 46 (34.7%) patients with negative ALNs in PET-CT scan finally showed involvement in histopathology report after SLNB resulting in upstage of the disease. The size of tumor deposits in sentinel nodes was significantly smaller than PET-positive ALNs (P = 0.01). Our observations correlate with the results of earlier studies published in the literature.

Conclusions

18F-FDG PET-CT scan cannot substitute SLNB for ALN screening in EBC. The limitations are most marked in smaller and micrometastatic tumor deposits in ALNs and may be attributed to limitations of PET resolution. However, PET-positive nodes showed good specificity for disease involvement in our study. Therefore, ALND can safely be performed by omitting SLNB in such cases.

Oncologic safety of breast conservation following NACT in women with locally advanced breast cancer

Introduction

Breast conservation surgery (BCS) is the accepted standard of treatment for early breast cancer, with evidence from randomized controlled and population-based studies. The oncological outcome of BCS in locally advanced breast cancer (LABC) is mainly available from retrospective series with a small sample size and a shorter follow-up duration.

Methods

A retrospective observational study of 411 non-metastatic LABC patients who received neoadjuvant chemotherapy (NACT) followed by surgery from 2011 to 2016. We retrieved the data from a prospectively maintained database and electronic medical records. Survival data were analyzed by Kaplan-Meier curves and Cox regression using Statistical Package for the Social Sciences 25 and STATA 14.

Results

146/411 (35.5%) women had BCS with a margin positivity rate of 3.42%. With a median follow-up of 64 months (IQR 61, 66), the local relapse rate was 8.9% in BCS and 8.3% after mastectomy. The estimated 5-year locoregional recurrence-free survival (LRFS), recurrence-free survival (RFS), distant disease-free survival (DDFS) and overall survival (OS) rates of BCS were 86.9%, 63.9%, 71% and 79.3%, and 90.1%, 57.9%, 58.3% and 71.5% in the mastectomy group. On univariate analysis, BCS showed superior survival outcomes compared to mastectomy (unadjusted HR (95% CI) for RFS: 0.70 (0.50-1), DDFS: 0.57 (0.39-0.84), OS: 0.58 (0.36-0.93)). After adjusting for age, cT stage, cN stage, poorer chemotherapy response (ypT0/is, N0) and radiotherapy, BCS and mastectomy groups were found comparable in terms of LRFS (HR: 1.1, 0.53-2.3), DDFS (HR: 0.67, 0.45-1.01), RFS (HR: 0.80, 0.55-1.17) and OS (HR: 0.69, 0.41-1.14).

Conclusion

BCS is technically feasible in LABC patients. LABC patients who respond well to NACT can be offered BCS without compromising survival outcomes.

Salvage Using Polatuzumab Vedotin Based Therapy in Relapsed Refractory Large B-Cell Lymphomas: Early Experience from a Real-World Middle-Income Setting Using Named-Patient Compassionate Access Program

Polatuzumab vedotin is a novel immunotherapy antibody-drug conjugate targeting CD79b. It has been used in relapsed/refractory (R/R) large B-cell lymphomas since its FDA approval in 2019. Presently, this drug is unaffordable or unavailable for patients in Lower-Middle Income Countries (LMIC) like India. This is a retrospective study of adult (> 18 years) patients with R/R large B-cell lymphoma failing two prior lines of therapy, who received Polatuzumab based salvage therapy on a compassionate or named-patient access program. Between May 2019 and April 2022, 10 patients received Polatuzumab vedotin, and 9 were evaluable. The most common regimen used was Polatuzumab-Bendamustine-Rituximab. Out of 43 infusions administered, the adverse event profile was manageable [One grade-2 infusion reaction, 4 patients developed grade 3-4 hematological toxicity and none had grade 3-4 non-hematological toxicities]. Ten infusions were administered in the day care service. After a median of 4.5 cycles (range 1-8), 4 patients achieved CR, 2 had partial response (PR), and 3 had progressive disease (PD). With a median follow up of 491 days (range 8-1048 days), four patients are alive (three in CR and one in PR), three patients have died and three patients were lost to follow up. Early real-world experience from a LMIC setting demonstrates feasibility and a favourable safety profile of Polatuzumab vedotin based approach, along with encouraging response rates in a subset of patients.

Subcategorization of Perineural Invasion and Its Impact on Survival in Patients with Oral Squamous Cell Carcinoma

BACKGROUND

Perineural invasion (PNI) is  recognized as a poor prognostic factor in oral squamous cell carcinoma (OSCC). However, the prognostic significance of further histologic  subcategorization of PNI is inconclusive. In this study, we determined the prognostic relevance of histologic subcategories of PNI and their correlation with the presence of other clinical and pathological parameters METHODS: This is a retrospective study of 207 homogeneously treated OSCC patients with histologically documented PNI from a single center. Univariate and multivariate survival outcomes, namely, local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS) of patients with various subcategories of PNI,namely- number of foci, size of the involved nerve, extratumoral or intratumoral extent, and intraneural or perineural location-were determined.

RESULTS

Within the histologic subcategories of PNI, tongue primary and presence of lymph node metastasis correlated significantly with the number of nerves involved with PNI. Larger size of involved nerve correlated with advanced tumor stage. Number of foci, extent, and location of PNI were not prognostically significant except size of the involved nerve which showed an inverse correlation with disease outcome as involvement of larger nerves displayed better outcomes in terms of DFS and LRFS but not of OS on multivariate analysis. Addition of adjuvant chemotherapy to radiotherapy emerged as a significant predictor of improved LRFS, DFS, and OS.

CONCLUSIONS

Histologic subcategorization of PNI did not have prognostic relevance in our study. Involvement of even small nerves was associated with poor prognosis. Addition of chemoradiation was seen to improve prognosis.

Systematically higher Ki67 scores on core biopsy samples compared to corresponding resection specimen in breast cancer: a multi-operator and multi-institutional study

Ki67 has potential clinical importance in breast cancer but has yet to see broad acceptance due to inter-laboratory variability. Here we tested an open source and calibrated automated digital image analysis (DIA) platform to: (i) investigate the comparability of Ki67 measurement across corresponding core biopsy and resection specimen cases, and (ii) assess section to section differences in Ki67 scoring. Two sets of 60 previously stained slides containing 30 core-cut biopsy and 30 corresponding resection specimens from 30 estrogen receptor-positive breast cancer patients were sent to 17 participating labs for automated assessment of average Ki67 expression. The blocks were centrally cut and immunohistochemically (IHC) stained for Ki67 (MIB-1 antibody). The QuPath platform was used to evaluate tumoral Ki67 expression. Calibration of the DIA method was performed as in published studies. A guideline for building an automated Ki67 scoring algorithm was sent to participating labs. Very high correlation and no systematic error (p = 0.08) was found between consecutive Ki67 IHC sections. Ki67 scores were higher for core biopsy slides compared to paired whole sections from resections (p ≤ 0.001; median difference: 5.31%). The systematic discrepancy between core biopsy and corresponding whole sections was likely due to pre-analytical factors (tissue handling, fixation). Therefore, Ki67 IHC should be tested on core biopsy samples to best reflect the biological status of the tumor.

Diagnostic performance and survival outcome following sentinel lymph node biopsy in breast cancer patients from a tertiary cancer centre in India

Background

Sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) for axillary staging in early node-negative breast cancer (BC) patients in developed countries. However, in resource-constrained developing countries, adoption of SLNB is slow due to logistic issues and lack of outcome data from non-screened BC cohort. Therefore, we aim to report diagnostic performance, surgical morbidity and survival outcome of SLNB in BC patients from a tertiary care cancer centre in India.

Methodology

1,521 consecutive early node-negative T1-3N0 BC patients having SLNB from 2011 to 2020 were included in the study. Data were retrieved from the institutional Redcap database and electronic medical records. Analysis was done using Stata14.

Results

SLNB was done by dual dye (methylene blue (MB) + radioisotope (RI)/indo cyanine green (ICG)) in 57.7%, MB only in 39.3%, and RI alone in 3% of patients. The identification rate (IR) and SLNB positivity rate were 96% and 27.7%, respectively. IR was highest (98%) with MB + ICG and lowest (94%) with MB alone SLNB. UltraSonoGraphy guided fine needle aspiration cytology of radiological suspicious nodes has significantly reduced the SLNB positivity rate from 34.6% to 26.4% (p < 0.01). One patient had skin necrosis, and 16 had persistent blue staining of the skin in the MB injection site. All were managed conservatively. The lymphedema rate was significantly higher (5.2%) in the ALND versus 0.5% in the SLNB alone patients (p < 0.05). In a median follow up of 27 months, the axillary recurrence rate was 0.04% (4/1,023), and false-negative rate was 0.9% in SLNB negative patients. There were 35 recurrences and 25 deaths in SLNB negative patients, with 10 years predicted disease-free survival of 81% (95% CI 66% to 89%) and overall survival of 79% (95% CI 59% to 90%).

Conclusions

SLNB should be offered as an axillary staging procedure to all eligible BC patients from developing countries to avoid the morbidity associated with ALND. Fluorescent dye can be used as an alternative for RI in a resource-constrained setup.

Dedifferentiated chordoma, a case report

Dedifferentiated chordoma is a rare variant of chordoma, exhibiting simultaneous presence of  conventional chordoma and component of high grade sarcoma. It occurs either de novo or in the form of high grade transformation of a conventional chordoma in a setting of recurrence or radiotherapy induced changes. Despite similar clinical manifestations, it shows significantly poorer survival among all variants of chordomas, making an accurate diagnosis important. We, herein, report a case of large chordoma in a 65 years old female, arising de novo in sacrum, where dedifferentiated component was present only focally, highlighting the importance of adequate grossing.

Relapsed Refractory Hodgkin Lymphoma and Brentuximab Vedotin-Bendamustine Combination Therapy as a Bridge to Transplantation: Real-World Evidence From a Middle-Income Setting and Literature Review

Introduction

Despite high cure rates with standard treatment, 30% patients with Hodgkin lymphoma develop relapsed or refractory (R/R) disease. Salvage therapy followed by autologous hematopoietic cell transplantation (HCT) is considered standard of care. Brentuximab Vedotin (Bv) in combination with Bendamustine (B) has been tested in the salvage setting with promising results.

Materials and Methodology

We conducted a single centre retrospective chart review of patients who received BBv salvage therapy to determine its activity and safety in patients with R/R classical Hodgkin lymphoma (HL). Between May 2011- December 2019, 179 patients were diagnosed with R/R HL.

Results

Thirty patients received BBv [median age: 30 (15-59) years, females (n=15)]. Primary refractory disease in 19 patients (63%), and 26 patients (87%) had advanced stage at treatment. Most patients received BBv after 2 prior lines of therapy [n=16 (53%)]. The median number of cycles of BBv were 3 (1-6). The number of BBv cycles delivered as outpatient was 63%. The most common Grade III/IV hematological adverse event was neutropenia [n=21, (70%)], while grade III/IV non-hematological toxicities included infections in 4 (13%), neuropathy in 4(13%), skin rash in 2 (7%), GI toxicities in 3 (10%) and liver dysfunction in 2 (7%) patients. The ORR and CR rates were 79% and 62%, respectively. Seventeen patients (57%) underwent an autologous HCT and 8 (26%) underwent an Allogeneic HCT (all haploidentical). The median follow up time from BBv administration was 12 months. Six patients died: 2 = disease progression, and 4 = non-relapse causes (Infection and sepsis = 2, GVHD=2). In addition to this, one patient progressed soon after HCT and another patient relapsed 22 months post HCT. Three year Overall survival (OS) and Event free survival (EFS) probability post-BBv treatment was 75% and 58%, respectively. OS and EFS analysis based on response (viz., CMR) to BBv demonstrated that patients in CMR had better survival probability [93% (p=0.0022) 3yr-OS and 72% (p=0.038) 3yr-EFS probability].

Conclusions

BBv is an active and well-tolerated salvage treatment for patients with R/R HL, even in refractory and advanced settings. In middle-income settings, cost constraints and access determine patient uptake of this regimen.

The tale of TILs in breast cancer: A report from The International Immuno-Oncology Biomarker Working Group

The advent of immune-checkpoint inhibitors (ICI) in modern oncology has significantly improved survival in several cancer settings. A subgroup of women with breast cancer (BC) has immunogenic infiltration of lymphocytes with expression of programmed death-ligand 1 (PD-L1). These patients may potentially benefit from ICI targeting the programmed death 1 (PD-1)/PD-L1 signaling axis. The use of tumor-infiltrating lymphocytes (TILs) as predictive and prognostic biomarkers has been under intense examination. Emerging data suggest that TILs are associated with response to both cytotoxic treatments and immunotherapy, particularly for patients with triple-negative BC. In this review from The International Immuno-Oncology Biomarker Working Group, we discuss (a) the biological understanding of TILs, (b) their analytical and clinical validity and efforts toward the clinical utility in BC, and (c) the current status of PD-L1 and TIL testing across different continents, including experiences from low-to-middle-income countries, incorporating also the view of a patient advocate. This information will help set the stage for future approaches to optimize the understanding and clinical utilization of TIL analysis in patients with BC.

Determinants of prognosis in patients with oral squamous cell carcinoma metastasizing to a single cervical lymph node

OBJECTIVES

Metastasis in a single lymph node without adverse tumour factors and perineural invasion has been assigned to a lower risk category by the ASCO recommendations of 2019. We analyzed patients with a single positive node with a view to identifying high risk features and their impact on prognosis within this subgroup.

MATERIALS AND METHODS

The study retrospectively analyzed 707 patients with OSCC. Descriptive statistics were used to compare distribution of clinicopathologic risk features between 323 N0 and 121 single node positive (N_s) patients. The N_s group was further analyzed for the impact of clinicopathologic factors on disease free (DFS) and overall survival (OS) using univariate and multivariate models.

RESULTS

The N_s group exhibited greater depth of invasion compared to the N0 group and significantly higher proportion of lymphovascular invasion (LVI), perineural invasion (PNI) and poorly differentiated tumors. Within the N_s group, primary tumor localised to the gingivobuccal subsite (HR 2.55, 1.18-5.52 95%CI, p = 0.02) and PNI (HR 2.55, 1.14-5.62, 95%CI p = 0.02) exhibited poor DFS. PNI also contributed to poor OS (HR 2.86, 1.27-6.47 95%CI, p = 0.01). Uninvolved margins (HR 0.46, 0.22-0.96 95%CI, p = 0.04) and chemoradiation (HR 0.18,0.05-0.68 95% CI, p = 0.01) improved OS.

CONCLUSION

Significant differences are noted in the prevalence of pathologic risk factors between the single node positive and node negative groups. Within the single node positive group, tumour factors like the gingivobuccal subsite, PNI and margin positivity impacted survival. Among nodal factors, deposit size of 12 mm or more and presence of ENE are pointers to poor prognosis. These patients would benefit from adjuvant treatment.

Diagnostic Performance of Indocyanine Green Plus Methylene Blue Versus Radioisotope Plus Methylene Blue Dye Method for Sentinel Lymph Node Biopsy in Node-Negative Early Breast Cancer

PURPOSE

Sentinel lymph node biopsy (SLNB) by dual-dye method (radioisotope plus blue) is the gold standard for axillary staging in patients with breast cancer, but in developing countries, logistic issues and financial constraint play a vital role. Recently, indocyanine green (ICG) has emerged as an alternative to radioisotope (technetium-99 [Tc-99]) for SLNB in breast cancer. This study compared the diagnostic performance of Tc-99 plus methylene blue (MB) dye versus ICG + MB dye SLNB.

METHODS

Two hundred seven patients with early breast cancer (T1-3N0) were included in the study from 2017 to 2019. SLNB was done either with Tc-99 + MB or with ICG + MB as per availability of radioisotope. SLN identification rate (IR), SLN positivity rate, and metastatic SLN counts were compared between the 2 groups.

RESULTS

IR was 199 (96%) of 207. IR was 95% in Tc-99 + MB compared with 97% with ICG + MB. The mean number of SLNs identified were 3.17 (standard deviation [SD], 1.84), with > 1 SLN identified in 87% patients by Tc-99 + MB. SLN was positive in 31.3% of patients with a metastatic SLN count of 0.37 (SD, 0.76). With ICG + MB, the number of SLNs was 2.73 (SD, 1.55), with > 1 SLN identified in 79% of patients. Twenty-eight percent of patients had positive SLNs, with a metastatic SLN count of 0.41 (SD, 0.77). A sharp decline in the availability of Tc-99 was observed, with 58% of patients in 2014 and only 12% of patients in 2018.

CONCLUSION

ICG is equivalent to Tc-99 for SLNB in early breast cancer and has a good potential to be adopted by surgeons in resource-constrained setups.

Reliability of Ki67 visual scoring app compared to eyeball estimate and digital image analysis and its prognostic significance in hormone receptor-positive breast cancer

We analysed the reproducibility of Ki67 labelling index (LI) between two scorers using the International Ki67 Working Group (IKWG) global methods on an Android application (APP), correlated the APP and eyeball estimate (EBE) with digital image analysis (DIA) scores and determined the prognostic significance of Ki67LI. Global weighted (GW) and global unweighted (GUW) Ki67 app scores of hormone receptor-positive and HER2 (human epidermal growth factor receptor 2)-negative breast cancer patients were obtained. Reproducibility of Ki67LI between 2 scorers and correlation of APP and EBE scores with DIA scores were performed. The prognostic significance of APP scores and its correlation with other clinico-pathologic variables were evaluated. The intra-class correlation coefficient (ICC) between 2 scorers showed excellent reliability with both GW and GUW methods. ICC between DIA and APP scores was significantly greater than DIA versus EBE. The three categories of APP scores based on median value and cut points of 10%, 18% and 38% were significantly associated with poor DFS. On multivariate analysis, significant association between Ki67LI, tumour size, nodal involvement and DFS was noted. Our study shows that the visual Ki67 scoring app is effective in bringing consistency to KI67LI and APP scores showed significant correlation with DFS.

Outcomes of diffuse large B-cell lymphoma in elderly patients-real-world experience from a middle-income country setting

Background

Diffuse large B-cell lymphoma (DLBCL) is the commonest subtype of lymphoma in the elderly and poses unique challenges in this group of patients. There is a need for more information on real-world outcomes across economic disparities.

Methods

Electronic Medical Record of 3,087 lymphomas (>18 years) were evaluated retrospectively, of which 842 (27%) patients were ≥65 years. Two hundred and twelve patients who were ≥65 years received first line treatment for DLBCL between May 2011 and Dec 2016. Demography, clinical features, associated co-morbidities, first line treatment outcomes and hospital costs were analysed. Patients were followed up till March 2020.

Results

The median age at presentation was 71 years. Gender ratio was 2.5:1. 38% patients presented with early-stage disease, 37% with low and low-intermediate International prognostic index, 49% with nodal disease. One or more co-morbidities were present in 58%. The commonest extra nodal site was gastro-intestinal (29%). Two-thirds of the patients presented with non-Germinal centre B subtype. The overall response (OR) to treatment was 72.5%. Patients who received anthracycline-based therapy (n = 124) and rituximab-based therapy (n = 159) had a median progression free survival (PFS), not reached and 47.0 months, respectively, versus 10 months and 7.9 months, respectively, for patients receiving non-anthracycline and non-rituximab therapies. At a median follow-up of 24 months, the 5-year overall survival and PFS are 44% and 41%, respectively, for the entire cohort.

Conclusions

DLBCL is a curable lymphoma in elderly patients with standard anthracycline and rituximab-based therapies. Improvement in outcomes largely depends on social and financial support to complete the scheduled treatments.

Pancreatic adenocarcinoma with primary tumor calcification and calcified liver metastasis: Report of a rare case and review of literature

Calcification is a feature of benign pancreatic diseases such as chronic calcific pancreatitis (CCP) or benign pancreatic tumors such as solid and papillary epithelial neoplasm of the pancreas and serous cystadenoma. The presence of calcification in a primary malignant pancreatic tumor is uncommon except for neuroendocrine tumors of the pancreas. Calcification in adenocarcinoma of the pancreas involving the primary tumor as well as the metastasis resulting thereof is extremely rare in the absence of CCP. To our knowledge, this is the first report of a case of primary adenocarcinoma of the pancreas that presented with calcification of the primary tumor as well as the metastatic liver nodules, accompanied by hypercalcemia.

Relapsed plasmablastic lymphoma in a HIV-negative patient: Pushing the envelope

This case emphasizes that, with the availability of novel immunotherapy agents (Daratumumab), and repurposed use of bortezomib, a patient with HIV-negative relapsed PBL can be treated successfully and consolidated with an allogeneic haploidentical hematopoietic cell transplantation.

Nodal yield and topography of nodal metastases from oral cavity squamous cell carcinoma - An audit of 1004 cases undergoing primary surgical resection

OBJECTIVES

Nodal metastasis is an important prognostic factor in oral squamous cell carcinoma (OSCC). Detailed topographic study of metastasis can guide surgical and adjuvant radiation treatment protocols.

METHODS

Retrospective analysis of distribution of nodal spread was done by auditing pathology records of 1004 patients who underwent primary surgical management at our center.

RESULTS

The median nodal yield was 41 (range of 9-166) nodes, per patient. Metastasis was present in 42.9% patients, of which 52.3% demonstrated extranodal extension. Reclassification by AJCC8 criteria resulted in up-staging in 35.6% patients (pN1, pN2a, pN2b, pN2c, pN3a and pN3b in 13.1%, 3.7%, 6.9%, 0.9%, 0%, 18.1% respectively). Ipsilateral levels Ib and IIa were involved in a quarter of patients each, while IIb, IV and V were involved in < 4%, 3% and 1% of patients, respectively. Contralateral nodal metastasis was present in 5.4%. Skip metastases to level IV were 2.2% and 1.2% for tongue and gingivobuccal primaries. Tongue primaries had a lower likelihood of involving level Ib, but higher of level IIa and III, compared to gingivobuccal primaries, and a lower likelihood of extranodal extension. Primary site did not influence nodal metastasis to levels IIb, IV or V, but other factors like lymphovascular invasion, pT stage and margin status had an influence.

CONCLUSION

This large series with high nodal yield, shows low level of metastasis to level IIb, IV and V, which can help modify future guidelines for extent of surgery and avoid targeted adjuvant radiation to specific levels.

Lymph node characteristics and their prognostic significance in oral squamous cell carcinoma

BACKGROUND

The prognostic significance of various histopathologic lymph node-based biomarkers in oral squamous cell carcinoma (OSCC) needs further evaluation.

METHODS

Retrospective analysis of 212 OSCC patients with regional metastasis to determine the association of extranodal extension (ENE), extent of ENE, size of metastatic deposit, lymph node yield (LNY), lymph node ratio (LNR), and topography of involvement with survival outcomes.

RESULTS

The presence of ENE, larger nodal deposit, higher pN stage, lymph nodes in the lower levels, and patients who did not receive adjuvant treatment had poor disease-free survival (DFS). In addition, more positive nodes and high LNR showed worse overall survival (OS). ENE beyond 5 mm resulted in poorer outcomes. Larger sizes of metastatic deposit predisposed to ENE. Multivariate analyses showed only lower level of neck involvement to affect both DFS and OS.

CONCLUSIONS

Lymph node metastasis to lower levels and other lymph node characteristics affect prognosis and must be considered in the evolution of staging systems for OSCC.

AutoIHC-Analyzer: computer-assisted microscopy for automated membrane extraction/scoring in HER2 molecular markers

Human epidermal growth factor receptor 2 (HER2) is one of the widely used Immunohistochemical (IHC) markers for prognostic evaluation amongst the patient of breast cancer. Accurate quantification of cell membrane is essential for HER2 scoring in therapeutic decision making. In modern laboratory practice, expert pathologist visually assesses the HER2-stained tissue sample under the bright field microscope for cell membrane assessment. This manual assessment is time consuming, tedious and quite often results in interobserver variability. Further, the burden of increasing number of patients is a challenge for the pathologists. To address these challenges, there is an urgent need with a rapid HER2 cell membrane extraction method. The proposed study aims at developing an automated IHC scoring system, termed as AutoIHC-Analyzer, for automated cell membrane extraction followed by HER2 molecular expression assessment from stained tissue images. A series of image processing approaches have been used to automatically extract the stained cells and membrane region, followed by automatic assessment of complete and broken membrane. Finally, a set of features are used to automatically classify the tissue under observation for the quantitative scoring as 0/1+, 2+ and 3+. In a set of surgically extracted cases of HER2-stained tissues, obtained from collaborative hospital for the testing and validation of the proposed approach AutoIHC-Analyzer and publicly available open source ImmunoMembrane software are compared for 90 set of randomly acquired images with the scores by expert pathologist where significant correlation is observed [(r = 0.9448; p < 0.001) and (r = 0.8521; p < 0.001)] respectively. The output shows promising quantification in automated scoring. LAY DESCRIPTION: In cancer prognosis amongst the patient of breast cancer, human epidermal growth factor receptor 2 (HER2) is used as Immunohistochemical (IHC) biomarker. The correct assessment of HER2 leads to the therapeutic decision making. In regular practice, the stained tissue sample is observed under a bright microscope and the expert pathologists score the sample as negative (0/1+), equivocal (2+) and positive (3+) case. The scoring is based on the standard guidelines relating the complete and broken cell membrane as well as intensity of staining in the membrane boundary. Such evaluation is time consuming, tedious and quite often results in interobserver variability. To assist in rapid HER2 cell membrane assessment, the proposed study aims at developing an automated IHC scoring system, termed as AutoIHC-Analyzer, for automated cell membrane extraction followed by HER2 molecular expression assessment from stained tissue images. The input image is preprocessed using modified white patch and CMYK and RGB colour space were used in extracting the haematoxylin (negatively stained cells) and diaminobenzidine (DAB) stain observed in the tumour cell membrane. Segmentation and postprocessing are applied to create the masks for each of the stain channels. The membrane mask is then quantified as complete or broken using skeletonisation and morphological operations. Six set of features were assessed for the classification from a set of 180 training images. These features are: complete to broken membrane ratio, amount of stain using area of Blue and Saturation channels to the image size, DAB to haematoxylin ratio from segmented masks and average R, G and B from five largest blobs in segmented DAB-masked image. These features are then used in training the SVM classifier with Gaussian kernel using 5-fold cross-validation. The accuracy in the training sample is found to be 88.3%. The model is then used for 90 set of unknown test sample images and the final labelling of stained cells and HER2 scores (as 0/1+, 2+ and 3+) are compared with the ground truth, that is expert pathologists' score from the collaborative hospital. The test sample images were also fed to ImmunoMembrane software for a comparative assessment. The results from the proposed AutoIHC-Analyzer and ImmunoMembrane software were compared with the expert pathologists' score where significant agreement using Pearson's correlation coefficient [(r = 0.9448; p < 0.001) and (r = 0.8521; p < 0.001) respectively] is observed. The results from AutoIHC-Analyzer show promising quantitative assessment of HER2 scoring.

Abstract P5-02-01: Analytical validation and prognostic potential of an automated digital scoring protocol for Ki67: An International Ki67 Working Group study

Background: The nuclear proliferation biomarker Ki67 has multiple potential roles in breast cancer, including aiding decisions based on prognosis, but has unacceptable between-laboratory variability. Here we tested an open source and calibrated automated digital image analysis (DIA) platform to: (i) Assess inter-laboratory reproducibility of automated Ki67 measurement among 17 participating labs and compare those with standardized pathologist-based visual scoring. (ii) Investigate the comparability of Ki67 measurement across corresponding core biopsy and whole section cases. (iii) Test prognostic potential of the built Ki67 scoring algorithms on an independent cohort.

Methods: Two sets of 60 previously stained slides containing 30 core-cut biopsy and 30 corresponding whole tumor sections from 30 ER+ breast cancer cases were sent to 17 participating labs for automated assessment of average Ki67 expression. The blocks were centrally cut and stained for Ki67 using the Mib-1 antibody. The QuPath (open-source software) DIA platform was used to evaluate tumoral Ki67 expression. Calibration of the DIA method was performed in our previous study (Acs et al, Lab Invest 2019). A detailed guideline for building an automated Ki67 scoring algorithm was sent to the participating labs. Visual scoring of average Ki67 expression was performed by pathologists according to published standardized methods (Leung et al, NPJ Br Cancer 2016; Leung et al, Histopath 2019). Locked down DIA Ki67 scoring algorithms were applied to a validation cohort: 222 breast cancer cases from the Karolinska University Hospital in whole section format. Sufficient reproducibility to declare analytical validity was defined as an Intra Class Correlation (ICC) with lower limit of 95% credible interval (CI) &gt;0.80. Markov Chain Monte Carlo routines for generalized linear mixed models were used to estimate ICCs and calculate corresponding CIs.

Results: The same-section ICC was 0.902 (CI: 0.852-0.949) across 17 labs using calibrated DIA platform on core biopsy slides and 0.845 (CI: 0.778-0.912) on whole sections. The different-section ICC across the 17 labs was 0.873 (CI: 0.806-0.932) scoring on core biopsy slides and 0.777 (CI: 0.670-0.874) on whole sections. The pathologist-based visual Ki67 scoring showed ICC of 0.860 for all comparisons, respectively (CI: 0.795-0.927). Similar to what was observed for visual Ki67 scoring, the DIA scores are higher for core biopsy slides compared to paired whole sections (p≤0.001; median difference: 5.31%; IQR: 11.50%). Ki67 scores of all locked down DIA algorithms correlates significantly (p≤0.023) with outcome on the validation cohort (observed hazard ratios range: 2.518-2.922).

Conclusions: Automated Ki67 evaluation using a calibrated, open-source DIA platform (QuPath) met the pre-specified criterion of success on core biopsies but not on whole sections in the multi-institutional setting. The systematic discrepancy between core biopsy and corresponding whole sections was likely due to pre-analytical factors (tissue handling, fixation) and intratumor heterogeneity. We found that different algorithms built according to calibrated DIA methods had similar prognostic potential. Assessment of clinical utility is planned.

Citation Format: Balazs Acs, Samuel C.Y. Leung, Kelley M. Kidwell, Indu Arun, Renaldas Augulis, Sunil S. Badve, Yalai Bai, Anita L. Bane, John M.S. Bartlett, Jane Bayani, Gilbert Bigras, Annika Blank, Signe Borgquist, Henk Buikema, Martin C. Chang, Robin L. Dietz, Andrew Dodson, Anna Ehinger, Susan Fineberg, Cornelia M. Focke, Dongxia Gao, Allen M. Gown, Carolina Gutierrez, Johan Hartman, Judith C. Hugh, Zuzana Kos, Anne-Vibeke Lænkholm, Arvydas Laurinavicius, Richard M. Levenson, Rustin Mahboubi-Ardakani, Mauro G. Mastropasqua, Takuya Moriya, Sharon Nofech-Mozes, C. Kent Osborne, Liron Pantanowitz, Frédérique M. Penault-Llorca, Tammy Piper, Mary Anne Quintayo, Tilman T. Rau, Stefan Reinhard, Stephanie Robertson, Takashi Sakatani, Roberto Salgado, Melanie Spears, Jane Starczynski, Tomoharu Sugie, Bert van der Vegt, Giuseppe Viale, Shakeel Virk, Lila A. Zabaglo, Daniel F. Hayes, Mitch Dowsett, Torsten O. Nielsen, David L. Rimm, International Ki67 in Breast Cancer Working Group, BIG-NABCG. Analytical validation and prognostic potential of an automated digital scoring protocol for Ki67: An International Ki67 Working Group study [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 P5-02-01.

Analytical validation of a standardised scoring protocol for Ki67 immunohistochemistry on breast cancer excision whole sections: an international multicentre collaboration

AIMS

The nuclear proliferation marker Ki67 assayed by immunohistochemistry has multiple potential uses in breast cancer, but an unacceptable level of interlaboratory variability has hampered its clinical utility. The International Ki67 in Breast Cancer Working Group has undertaken a systematic programme to determine whether Ki67 measurement can be analytically validated and standardised among laboratories. This study addresses whether acceptable scoring reproducibility can be achieved on excision whole sections.

METHODS AND RESULTS

Adjacent sections from 30 primary ER⁺ breast cancers were centrally stained for Ki67 and sections were circulated among 23 pathologists in 12 countries. All pathologists scored Ki67 by two methods: (i) global: four fields of 100 tumour cells each were selected to reflect observed heterogeneity in nuclear staining; (ii) hot-spot: the field with highest apparent Ki67 index was selected and up to 500 cells scored. The intraclass correlation coefficient (ICC) for the global method [confidence interval (CI) = 0.87; 95% CI = 0.799-0.93] marginally met the prespecified success criterion (lower 95% CI ≥ 0.8), while the ICC for the hot-spot method (0.83; 95% CI = 0.74-0.90) did not. Visually, interobserver concordance in location of selected hot-spots varies between cases. The median times for scoring were 9 and 6 min for global and hot-spot methods, respectively.

CONCLUSIONS

The global scoring method demonstrates adequate reproducibility to warrant next steps towards evaluation for technical and clinical validity in appropriate cohorts of cases. The time taken for scoring by either method is practical using counting software we are making publicly available. Establishment of external quality assessment schemes is likely to improve the reproducibility between laboratories further.

Prevalence estimation of microsatellite instability in colorectal cancers using tissue microarray based methods - A tertiary care center experience

Aim

Microsatellite instability (MSI) pathway is known to be implicated in carcinogenesis of 15% colorectal carcinomas (CRC), including 2%-3% of cases of Lynch syndrome, as per western literature. MSI status has important prognostic and therapeutic implications. The prevalence of MSI in Indian CRC patients is unknown. We aimed to determine the prevalence by studying 231 consecutive unselected cases of CRC.

Methods

Tissue microarrays using duplicate cores per case for 141 cases, and whole tissue sections for 90 cases, were used. Immunohistochemistry with four mismatch repair (MMR) markers - MLH1, MSH2, MSH6, and PMS2 was performed. Molecular analysis for MSI status was performed in 18 randomly selected cases. Correlation with various clinical and histopathological features was done using univariate and multivariate analysis.

Results

Loss of MMR immunohistochemical (IHC) was seen in 53/231 cases, i.e. 22.94% (95% confidence interval 17.52%-28.36%). MLH1-PMS2 dual loss comprised 13.9%, MSH2-MSH6 7.4%, and isolated PMS2 loss in 1.73% of cases. Univariate analysis showed significant association with age (<60 years), right-sided tumor location, histologic type, high grade, the presence of severe intratumoral lymphocytic (ITL) and peri-tumoral lymphocytic response, and N0 nodal stage. On multivariate analysis, independent variables were age < 60 years, right-sided location, and severe ITL. Molecular testing for MSI corroborated with the IHC results.

Conclusion

The study results show a slightly higher prevalence of MSI-H phenotype, compared to Western literature, stressing the need for more widespread testing for better clinical management and identification of possible hereditary colon cancer syndrome.

A subtype of cancer-associated fibroblasts with lower expression of alpha-smooth muscle actin suppresses stemness through BMP4 in oral carcinoma

Cancer-associated fibroblasts (CAFs) demonstrate the characteristics of myofibroblast differentiation by often expressing the ultrastructure of alpha-smooth muscle actin (αSMA). However, heterogeneity among cancer-associated fibroblasts (CAFs), with respect to αSMA expression, has been demonstrated in several clinical studies of oral cancer. Like normal stem cells, stem-like cancer cells (SLCCs) are also regulated extrinsically by its microenvironment; therefore, we postulated that the heterogeneous oral-CAFs would differently regulate oral-SLCCs. Using transcriptomics, we clearly demonstrated that the gene expression differences between oral tumor-derived CAFs were indeed the molecular basis of heterogeneity. This also grouped these CAFs in two distinct clusters, which were named as C1 and C2. Interestingly, the oral-CAFs belonging to C1 or C2 clusters showed low or high αSMA-score, respectively. Our data with tumor tissues and in vitro co-culture experiments interestingly demonstrated a negative correlation between αSMA-score and cell proliferation, whereas, the frequency of oral-SLCCs was significantly positively correlated with αSMA-score. The oral-CAF-subtype with lower score for αSMA (C1-type CAFs) was more supportive for cell proliferation but suppressive for the self-renewal growth of oral-SLCCs. Further, we found the determining role of BMP4 in C1-type CAFs-mediated suppression of self-renewal of oral-SLCCs. Overall, we have discovered an unexplored interaction between CAFs with lower-αSMA expression and SLCCs in oral tumors and provided the first evidence about the involvement of CAF-expressed BMP4 in regulation of self-renewal of oral-SLCCs.

Sentinel and Non-Sentinel Lymph Node Metastasis Prediction and Validation of the MSKCC Nomograms for Indian Breast Cancer Patients

Background: Sentinel lymph node (SLN) biopsy accurately stages the axilla, but is time consuming and resource intensive. Nomograms and scoring systems have been developed, based on clinical and pathologic data available before surgery, to attempt to predict the likelihood of lymph node metastasis before surgery. As the management of the axilla in patients with low nodal burden changes, it is also important to predict whether there will be further axillary disease in patients with a positive SLN. Aim: To explore the risk factors for SLN and non-SLN metastasis in Indian women with breast cancer, by analysis of clinical and pathologic data. To assess the validity and clinical utility of two MSKCC nomograms that predicts axillary lymph node status for Western patients. Methods: Clinical data, and pathologic data available from core biopsy, for a consecutive series of women having SLNB was analyzed, and was plotted on two MSKCC nomograms. Univariate analysis was done by χ2 and Fischer exact tests and multivariate analysis was done by logistic regression method. A receiver-operating characteristic (ROC) curve was drawn and predictive accuracy was assessed by calculating the area under the ROC curve (AUC). Results: 34% (89 out of 256) of our patients had SLN positivity. When correlated with SLN metastasis by univariate analysis, LVI (χ2 = 80, P ≤ 0.001), PNI (χ2 = 13.36, P ≤ 0.001), ER+ (χ2 = 6.85, P = 0.009), PR+ (χ2 = 7.1, P = 0.008) and age ( P = 0.03) were significant. However, multivariate analysis showed that age (OR=1.04, P = 0.007) and LVI (OR=0.07, P ≤ 0.001) were identified as independent predictors for SLN metastasis. The area under the ROC curve was 0.772 and it fairly correlated with MSKCC nomogram. Patients with MSKCC scores lower than 38% had a frequency of SLN metastasis of 7.7% (5/65) and this cut-off could be used as a guide for not doing frozen section analysis in this subgroup. Further axillary dissection showed 41% (38 out of 92) had non-sentinel nodes positive. When correlated with non-SLN metastasis by univariate analysis, LVI (χ2 = 8.8, P = 0.003), PNI (χ2 = 6.85, P = 0.009), and extracapsular extension (χ2 = 4.18, P = 0.04) were significant. Number of SLN negative ( P = 0.01), SLN ratio (number of SLN positive/total number of SLN removed) ( P = 0.01) and size of SLN metastasis ( P = 0.002) were significant. However, multivariate analysis showed that only size of SLN metastasis (OR=0.845, P = 0.02) was identified as independent predictor for non-SLN metastasis. The area under the ROC curve was 0.66 and it poorly correlated with MSKCC nomogram. Conclusion: The MSKCC nomogram can provide a fairly accurate prediction of the probability of SLN metastasis, but is not for non-SLN metastasis. An institutional nomogram for non-SLN metastasis, including additional factors such as size of SLN metastasis, may improve prediction.

Abstract P2-03-01: Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration

Aims: (i) Determine whether between-observer reproducibility for Ki67 when assessed on whole sections according to a standardized scoring protocol is adequate for clinical application. (ii) Compare between-observer reproducibility of Ki67 scores assessed on hot-spots to scores using a global method that averages across a tissue section.

Background: The nuclear proliferation biomarker Ki67 has multiple potential roles in breast cancer, including aiding decisions based on prognosis, but unacceptable levels of between-laboratory variability have been observed. The International Ki67 in Breast Cancer Working Group has undertaken a systematic program to determine whether Ki67 measurement can be analytically validated and standardized across labs. In phase 1, variability in visual interpretation was identified as an important source of variability. Phases 2 and 3a showed that adherence to defined scoring methods substantially improved reproducibility in scoring tissue microarrays and core-cut biopsies. We now assess whether acceptable reproducibility can be achieved on whole sections.

Methods: Adjacent sections from 30 primary ER+ breast cancers were centrally stained for Ki67 to assemble 4 sets of 30 stained tumor sections, circulated around 23 labs in 12 countries. Ki67 was scored by 2 methods by all labs: (a) global: 4 fields of 100 tumor cells each were selected to reflect observed heterogeneity in nuclear staining (b) hot-spot: the field with highest Ki67 percentage of tumor cells with nuclear staining was selected and up to 500 cells scored. Ki67 scores were log2-transformed for statistical analyses and back-transformed for presentation. The primary objective was to assess whether either method could achieve an intraclass correlation coefficient (ICC) significantly greater than 0.8, considered substantial to almost-perfect reproducibility. Secondary objectives were to assess which method had highest observed ICC and to assess whether observers identified the same “hot-spots”.

Results: ICC for the global method was 0.87 (95%CI: 0.799-0.93), marginally meeting the prespecified success criterion. The ICC for the hot-spot method was 0.83 (95%CI: 0.74-0.90) and had a CI extending below the success criterion. Across the 23 labs, geometric mean value of the 30 scores ranged from 8.5 to 19.6 for the global method and from 12.8 to 30.3 for the hot-spot method. The overall mean (95% CI) of these values was 12.9 (11.9-14.0) and 20.9 (19.1-22.8), respectively. Visually, between-laboratory agreement in location of selected hot-spot varies between cases. The median times for scoring were 9 and 6 minutes for global and hot-spot methods respectively.

Conclusions: The global method marginally met the prespecified criterion of success; it should now be evaluated for clinical validity in appropriate cohorts of cases. The hot-spot method was observed to have slightly less reproducibility between labs. The time taken for scoring by either method is practical using counting software we are making publicly available. Establishment of external quality assessment schemes is likely to improve the reproducibility between labs further.

(Supported by a grant from the Breast Cancer Research Foundation)

Citation Format: Nielsen TO, Leung SCY, Zabaglo LA, Arun I, Badve SS, Bane AL, Bartlet JMS, Borgquist S, Chang MC, Dodson A, Ehinger A, Fineberg S, Focke CM, Gao D, Gown AM, Gutierrez C, Hugh JC, Kos Z, Lænkholm A-V, Mastropasqua MG, Moriya T, Nofech-Mozes S, Osborne CK, Penault-Llorca FM, Piper T, Sakatani T, Salgado R, Starczynski J, Sugie T, van der Vegt B, Viale G, Hayes DF, McShane LM, Dowsett M. Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-03-01.

Quality Indicators for Sentinel Lymph Node Biopsy in Breast Cancer: Applicability and Clinical Relevance in a Non-screened Population

Quality Indicators for Sentinel Lymph Node Biopsy in Breast Cancer: Applicability and Clinical Relevance in a Non-screened Population: sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) as standard of care for management of early breast cancer. This study assessed our SLNB program against 11 published quality indicators (QIs). All breast cancer patients who underwent SLNB in our centre from June 2013-Dec 2015 were included. Clinical, pathological and follow-up data were extracted from the institutional REDCap data system. Analysis was done with SPSS 23. Following validation, 234 patients had SLNB, always performed along with primary surgery. Identification rate was 95.3% and > 1 SLN was identified in 72% of patients. SLNB positivity was 33%, of these, 100% underwent ALND. Overall 91% of QI eligible patients underwent SLNB. No ineligible patients (T4) underwent SLNB. For the patients who had radio colloid, injection criteria were met for 100%. Pathological evaluation and reporting criteria were met for 100% of patients. There were no axillary recurrences in a median follow-up of 2 years. 7.6% patients had SLN negative on frozen section but positive on final histology. 7.2% of patients with clinical negative nodes had pN2 disease in final histopathology report after surgery. Sixty percent of patients who had completion ALND had only positive SLN. This study supports the applicability of published QI of SLNB in a non-screened cohort of early breast cancer patients. Although QI were useful, modification based on patient characteristics and resource availability may be needed. These indicators can be used as audit tools to improve the overall accuracy of the procedure.

AutoIHC-scoring: a machine learning framework for automated Allred scoring of molecular expression in ER- and PR-stained breast cancer tissue

In prognostic evaluation of breast cancer Immunohistochemical (IHC) markers namely, oestrogen receptor (ER) and progesterone receptor (PR) are widely used. The expert pathologist investigates qualitatively the stained tissue slide under microscope to provide the Allred score; which is clinically used for therapeutic decision making. Such qualitative judgment is time-consuming, tedious and more often suffers from interobserver variability. As a result, it leads to imprecise IHC score for ER and PR. To overcome this, there is an urgent need of developing a reliable and efficient IHC quantifier for high throughput decision making. In view of this, our study aims at developing an automated IHC profiler for quantitative assessment of ER and PR molecular expression from stained tissue images. We propose here to use CMYK colour space for positively and negatively stained cell extraction for proportion score. Also colour features are used for quantitative assessment of intensity scoring among the positively stained cells. Five different machine learning models namely artificial neural network, Naïve Bayes, K-nearest neighbours, decision tree and random forest are considered for learning the colour features using average red, green and blue pixel values of positively stained cell patches. Fifty cases of ER- and PR-stained tissues have been evaluated for validation with the expert pathologist's score. All five models perform adequately where random forest shows the best correlation with the expert's score (Pearson's correlation coefficient = 0.9192). In the proposed approach the average variation of diaminobenzidine (DAB) to nuclear area from the expert's score is found to be 7.58%, as compared to 27.83% for state-of-the-art ImmunoRatio software.

MRF-ANN: a machine learning approach for automated ER scoring of breast cancer immunohistochemical images

Molecular pathology, especially immunohistochemistry, plays an important role in evaluating hormone receptor status along with diagnosis of breast cancer. Time-consumption and inter-/intraobserver variability are major hindrances for evaluating the receptor score. In view of this, the paper proposes an automated Allred Scoring methodology for estrogen receptor (ER). White balancing is used to normalize the colour image taking into consideration colour variation during staining in different labs. Markov random field model with expectation-maximization optimization is employed to segment the ER cells. The proposed segmentation methodology is found to have F-measure 0.95. Artificial neural network is subsequently used to obtain intensity-based score for ER cells, from pixel colour intensity features. Simultaneously, proportion score - percentage of ER positive cells is computed via cell counting. The final ER score is computed by adding intensity and proportion scores - a standard Allred scoring system followed by pathologists. The classification accuracy for classification of cells by classifier in terms of F-measure is 0.9626. The problem of subjective interobserver ability is addressed by quantifying ER score from two expert pathologist and proposed methodology. The intraclass correlation achieved is greater than 0.90. The study has potential advantage of assisting pathologist in decision making over manual procedure and could evolve as a part of automated decision support system with other receptor scoring/analysis procedure.

Automated characterization and counting of Ki-67 protein for breast cancer prognosis: A quantitative immunohistochemistry approach

Ki-67 protein expression plays an important role in predicting the proliferative status of tumour cells and deciding the future course of therapy in breast cancer. Immunohistochemical (IHC) determination of Ki-67 score or labelling index, by estimating the fraction of Ki67 positively stained tumour cells, is the most widely practiced method to assess tumour proliferation (Dowsett et al. 2011). Accurate manual counting of these cells (specifically nuclei) due to complex and dense distribution of cells, therefore, becomes critical and presents a major challenge to pathologists. In this paper, we suggest a hybrid clustering algorithm to quantify the proliferative index of breast cancer cells based on automated counting of Ki-67 nuclei. The proposed methodology initially pre-processes the IHC images of Ki-67 stained slides of breast cancer. The RGB images are converted to grey, L*a*b*, HSI, YCbCr, YIQ and XYZ colour space. All the stained cells are then characterized by two stage segmentation process. Fuzzy C-means quantifies all the stained cells as one cluster. The blue channel of the first stage output is given as input to k-means algorithm, which provides separate cluster for Ki-67 positive and negative cells. The count of positive and negative nuclei is used to calculate the F-measure for each colour space. A comparative study of our work with the expert opinion is studied to evaluate the error rate. The positive and negative nuclei detection results for all colour spaces are compared with the ground truth for validation and F-measure is calculated. The F-measure for L*a*b* colour space (0.8847) provides the best statistical result as compared to grey, HSI, YCbCr, YIQ and XYZ colour space. Further, a study is carried out to count nuclei manually and automatically from the proposed algorithm with an average error rate of 6.84% which is significant. The study provides an automated count of positive and negative nuclei using L*a*b*colour space and hybrid segmentation technique. Computerized evaluation of proliferation index can aid pathologist in assessing breast cancer severity. The proposed methodology, further, has the potential advantage of saving time and assisting in decision making over the present manual procedure and could evolve as an assistive pathological decision support system.

PAX-5 Positivity in Anaplastic Lymphoma Kinase-Negative Anaplastic Large Cell Lymphoma: A Case Report and Review of Literature

Anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma (ALCL) is a subtype of T-cell lymphomas that may mimic several other malignancies morphologically. With the help of immunohistochemistry, most cases of ALCL can be diagnosed on the basis of expression of T-cell lineage associated antigens. However, aberrations in the expression of immunohistochemical markers pose diagnostic challenges. The morphological and immunophenotypic features of ALCL show considerable overlap with classical Hodgkin lymphoma (CHL), which is a B-cell lymphoma. The 2008 World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues suggests that staining for the B-cell transcription factor, paired box 5 (PAX-5), is helpful in differentiating between them, as it is weakly positive in most CHL and should be negative in ALCL. We report a rare case of ALK-negative ALCL, which was positive for PAX-5 and CD15, mimicking CHL by immunohistochemistry, resulting in a diagnostic dilemma.

Outcomes Following a Moderately Hypofractionated Adjuvant Radiation (START B Type) Schedule for Breast Cancer in an Unscreened Non-Caucasian Population

AIMS

Breast cancer is the most common cancer in women. Western data have confirmed hypofractionated radiation therapy to be safe and effective in the adjuvant radiation therapy of breast cancers. We report the disease-related outcomes in a non-Caucasian, unscreened population treated with hypofractionated radiation.

MATERIALS AND METHODS

Unselected case notes of patients presenting to a tertiary cancer centre between June 2011 and December 2013 were reviewed from the electronic hospital case records. Patients with a diagnosis of non-metastatic invasive non-sarcomatous breast cancer were identified. Demographic information, oestrogen receptor (ER), progesterone receptor (PR), HER2 status, pathological tumour, nodal stage at diagnosis and outcomes of treatment, including systemic therapies, surgery and hypofractionated radiation, were documented. Local recurrence rates, disease-free survival (DFS) and overall survival were calculated.

RESULTS

Overall 925 patents were identified, median age 53.0 years (interquartile range 45-61), 330 of whom had neoadjuvant chemotherapy. The median follow-up time was 22.6 months and 23.5 months for overall and neoadjuvant chemotherapy groups, respectively. ER, PR and HER2 status was available in 788 patients, 77.2% of whom were ER/PR positive, 14.7% had triple negative disease, while 9.5% were HER2 rich. Overall, 34.2% (113 patients) underwent breast conservation surgery; 744 (80.4%) patients were treated with systemic chemotherapy and 878 (94.9%) patients received adjuvant radiation therapy, of whom 407 (44.0%) received supraclavicular-fossa radiotherapy. Overall survival, DFS and locoregional recurrence-free survival (LRRFS) for the overall group were 93%, 86.9% and 97.1%, respectively. LRRFS in the breast conservation surgery versus mastectomy groups were 99% versus 95.5% (P=0.003), with more node-positive patients in the mastectomy group. Stage N0/1 had better LRRFS compared with N2/2 (99.1% versus 95.7%); 94.3% versus 82.3%; P=0.005, 0.000. Grade 3 (53.8%) tumours had worse overall survival compared with grade 1 or grade 2 disease (89.6% versus 100% and 96.4%; P<0.001) although the LRRFS was not significantly different between the groups (98.9% versus 97.8%; P=0.37). There was no difference in LRRFS based on molecular subtypes.

CONCLUSION

Local recurrence rates following hypofractionated radiation in our population were comparable with those reported by the START trialists and were found to be safe in the medium term for patients irrespective of breast conservation surgery/mastectomy or radiotherapy to the supraclavicular field. Molecular group frequencies were comparable with Western populations but did not affect LRRFS.

Analytical validation of a standardized scoring protocol for Ki67: phase 3 of an international multicenter collaboration

Pathological analysis of the nuclear proliferation biomarker Ki67 has multiple potential roles in breast and other cancers. However, clinical utility of the immunohistochemical (IHC) assay for Ki67 immunohistochemistry has been hampered by unacceptable between-laboratory analytical variability. The International Ki67 Working Group has conducted a series of studies aiming to decrease this variability and improve the evaluation of Ki67. This study tries to assess whether acceptable performance can be achieved on prestained core-cut biopsies using a standardized scoring method. Sections from 30 primary ER+ breast cancer core biopsies were centrally stained for Ki67 and circulated among 22 laboratories in 11 countries. Each laboratory scored Ki67 using three methods: (1) global (4 fields of 100 cells each); (2) weighted global (same as global but weighted by estimated percentages of total area); and (3) hot-spot (single field of 500 cells). The intraclass correlation coefficient (ICC), a measure of interlaboratory agreement, for the unweighted global method (0.87; 95% credible interval (CI): 0.81–0.93) met the prespecified success criterion for scoring reproducibility, whereas that for the weighted global (0.87; 95% CI: 0.7999–0.93) and hot-spot methods (0.84; 95% CI: 0.77–0.92) marginally failed to do so. The unweighted global assessment of Ki67 IHC analysis on core biopsies met the prespecified criterion of success for scoring reproducibility. A few cases still showed large scoring discrepancies. Establishment of external quality assessment schemes is likely to improve the agreement between laboratories further. Additional evaluations are needed to assess staining variability and clinical validity in appropriate cohorts of samples.

NK/T Cell Lymphoma: A Tertiary Centre Experience

Extranodal NK/T-cell lymphoma (ENKTL), nasal type, is a rare type of non-Hodgkin lymphoma that is commonly seen in East Asian countries and is associated with Epstein-Barr virus infection. This is a retrospective study where we describe nine cases of ENKTL; nasal type diagnosed and treated at our center over a period of 2 years. These cases were analyzed retrospectively for clinical presentation (age, sex, site of involvement), immunophenotype, treatment, response and toxicity profile. Sino-nasal symptoms (blocked nose, headache, epistaxis, regurgitation) were the most common presenting complaints (n = 8). Almost 67 % (n = 6/9) of the cases were referred from Bhutan. Necrosis and angiocentricity were the commonest histological features. Depending on the stage of the disease patient were initially treated with chemotherapy (SMILE/CHOP) and Radiotherapy (IFRT). We describe our experience of management of ENKTL, where we observe that Bhutan could be endemic region for this rare tumour.

Clear cell renal cell carcinoma with hemangioblastoma-like features: A recently described pattern with unusual immunohistochemical profile

The diagnosis of clear cell renal cell carcinoma may sometimes pose challenges because of the presence of uncharacteristic morphology, varied immunophenotypic patterns and due to lack of molecular or genetic determinants. More often, the morphological variations can be easily overlooked in routine practice and a more common diagnosis is usually put forward. Solid, acinar and alveolar are the common patterns described in the literature. We report a recently described pattern of clear cell renal cell carcinoma which has hemangioblastoma-like morphology and an unusual immunoprofile. In our case, the tumor showed a diffuse hemangioblastoma-like pattern and diffuse positivity for Alpha-inhibin on immunohistochemistry. A thorough literature search, extensive sampling and an expanded immunohistochemistry panel revealed a clear cell renal cell carcinoma component. Presence of renal vein thrombosis and focal necrosis were other helpful features in discerning the malignant nature of tumor.