Morphometric analysis, ploidy and response to chemotherapy in squamous carcinomas of the head and neck

PanCancer insights from The Cancer Genome Atlas: the pathologist's perspective

The Cancer Genome Atlas (TCGA) represents one of several international consortia dedicated to performing comprehensive genomic and epigenomic analyses of selected tumour types to advance our understanding of disease and provide an open-access resource for worldwide cancer research. Thirty-three tumour types (selected by histology or tissue of origin, to include both common and rare diseases), comprising >11 000 specimens, were subjected to DNA sequencing, copy number and methylation analysis, and transcriptomic, proteomic and histological evaluation. Each cancer type was analysed individually to identify tissue-specific alterations, and make correlations across different molecular platforms. The final dataset was then normalized and combined for the PanCancer Initiative, which seeks to identify commonalities across different cancer types or cells of origin/lineage, or within anatomically or morphologically related groups. An important resource generated along with the rich molecular studies is an extensive digital pathology slide archive, composed of frozen section tissue directly related to the tissues analysed as part of TCGA, and representative formalin-fixed paraffin-embedded, haematoxylin and eosin (H&E)-stained diagnostic slides. These H&E image resources have primarily been used to verify diagnoses and histological subtypes with some limited extraction of standard pathological variables such as mitotic activity, grade, and lymphocytic infiltrates. Largely overlooked is the richness of these scanned images for more sophisticated feature extraction approaches coupled with machine learning, and ultimately correlation with molecular features and clinical endpoints. Here, we document initial attempts to exploit TCGA imaging archives, and describe some of the tools, and the rapidly evolving image analysis/feature extraction landscape. Our hope is to inform, and ultimately inspire and challenge, the pathology and cancer research communities to exploit these imaging resources so that the full potential of this integral platform of TCGA can be used to complement and enhance the insightful integrated analyses from the genomic and epigenomic platforms. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Basic fibroblast growth factor and angiogenesis in squamous carcinoma of the tongue

The relationship between basic fibroblast growth factor (bFGF), receptors for bFGF and neoangiogenesis was investigated in 51 patients with squamous cell carcinoma of the tongue, 26 of whom had metastatic disease in cervical lymph nodes. Vessels were demonstrated by immunocytochemical labelling for CD34 and expressed as raw counts and volume-weighted counts. bFGF protein and its receptors FGFR1(flg) and FGFR2(bek), were demonstrated using immunocytochemical labelling. In situ hybridisation for bFGF mRNA was performed using a 250-bp digoxigenin-labelled RNA probe. In normal epithelium, the expression of bFGF protein and mRNA was more intense in the basal layer, while receptors for bFGF were expressed more strongly in the superficial parts. In carcinomas, expression of bFGF was greater in the more poorly-differentiated cells, but showed no relation to the overall tumour differentiation. There was strong bFGF expression in tumour-infiltrating lymphocytes. The expression of bFGF receptors was variable, with FGFR2 being particularly high in areas of keratinisation. There were no consistent changes in bFGF or receptor expression between primary carcinomas and their lymph node metastases, and there was no correlation with measures of vascularity or tumour growth pattern. bFGF is synthesised by all squamous carcinomas and has the potential to modulate angiogenesis. However, these data suggest that changes in the expression of bFGF and its receptors are not related to the intensity of neoangiogenesis in lingual carcinomas or their nodal metastases.

Neoangiogenesis and squamous cell carcinoma of the tongue

The relationship between neoangiogenesis and prognosis was investigated in 51 patients with surgically resected squamous carcinomas of the tongue. Twenty-six patients had lymph node metastases treated by radical neck dissection. Potential methodological sources of variation in vascular counts were examined. Vessels were immunolabeled for CD34, and the vessel counts (VC)--as well as the vessel counts adjusted for tumor area (VV)--were obtained in the most vascular parts of the carcinomas. Vascular hot spots were distributed throughout the carcinomas. The VC per hot spot increased with increasing size of carcinoma, and was higher in the resected carcinoma than in the diagnostic biopsy in four of eight cases. VC was not related to the growth pattern of the carcinoma or to metastasis, but patients with nodal metastases tended to have a lower VV than those with no metastases (p = 0.049). The tumor-specific survival of the whole group was 59%, and patients with nodal metastases had a shorter survival than those without metastases (p = 0.008). Cox's proportional hazards model demonstrated that carcinomas with a low VC tended to have a good prognosis (p = 0.023). The results from this relatively small series of cases support the hypothesis that some measures of neoangiogenesis are independent predictors of the spread and prognosis of lingual carcinomas. The variations in methodology among different studies currently preclude an accurate assessment of the prognostic significance of neoangiogenesis.

DNA ploidy analysis of squamous cell carcinomas of the oral and maxillofacial region: clinical and pathologic correlations

DNA ploidy was investigated in 61 specimens obtained from 25 patients with squamous carcinoma of the oral and maxillofacial region. Biopsy specimens of normal tissue surrounding the tumor were also obtained in six patients. Single-cell suspensions for flow cytometric analysis were prepared. The DNA ploidy and histogram were calculated and compared with the histologic grade, presence of lymph node metastases, and course of the disease. The ploidy of the main stemline was peridiploid in 17 carcinomas, hyperdiploid in three, and aneuploid in five. Histologic grade but not nodal involvement was associated with the ploidy of the main stemline. Of 15 multisampled carcinomas 13 showed constant DNA ploidy and histogram classification. In the other two major changes in DNA ploidy (from peridiploid to hyperdiploid in the first and from peridiploid to aneuploid in the second) were found. Survival information was available for 24 patients. Ploidy values higher or lower than 2.5 c were strongly predictive of both overall (p < 0.001) and relapse-free survival (p < 0.001). The lymph node status proved a powerful prognostic indicator (p = 0.014) but was not related to the relapse-free time of survival. Multiparametric evaluation of survival revealed an independent role of both DNA ploidy and nodal involvement in the prognosis of squamous carcinoma of the oral and maxillofacial region.

Morphological predictors of survival in early and advanced gastric carcinoma

In 351 patients with gastric carcinomas resected for cure, the relationship between macroscopic and microscopic features and survival was studied by univariate and multivariate analyses. In the multivariate survival analysis with covariates according to the Cox regression model, in early cancer all significant correlations to survival rate are covered by the stage grouping according to the UICC schedule of 1987. In advanced gastric carcinoma the UICC stage and, in addition, the Borrmann type and the intensity of cellular infiltration are effective. By additional consideration of these two variables an extended pathological staging schedule is proposed. It has the advantage of better discrimination between patients who differ in prognosis and seems to improve the prognostic prediction of outcome. Testing of this extended staging system in larger collectives is recommended.