Dysglycemia in non-functioning pancreatic neuroendocrine tumors (NF-PNET): Further insights into an under recognized entity

Objective

Pancreatic neuroendocrine tumors (PNETs) are rare, but their incidence has risen significantly in recent years. Whereas diabetes mellitus (DM) is recognized in association with chronic pancreatitis and pancreatic cancer, it has not been well-characterized concerning non-functioning (NF)-PNETs.Study aim: to determine whether NF-PNETs are associated with DM/ Pre-DM and characterize the features of this putative association.

Methods

Retrospective study to evaluate rate of Pre-DM /DM in subjects with NF-PNETs.

Results

Study cohort of 129 patients with histologically confirmed NF-PNETs, ∼60% were men (M/F: 77/52). Abnormal glucose metabolism that preceded any treatment was seen in 70% of this cohort: overt DM in 34% and Pre-DM in 36% of the subjects. However, during follow-up, the overall prevalence rose to 80.6%, owing exclusively to newly diagnosed DM in subjects who received treatment.Patients with DM/Pre-DM were older (65 ± 11; 54 ± 14; p < 0.0001), the tumor was more commonly localized in the pancreatic body and tail (76.5% vs. 23.5% p = 0.03), while BMI (27 ± 6 vs. 28 ± 5 kg/m2), and tumor size (2.4 ± 2 vs. 2.9 ± 3.2 cm) were similar. The relative prevalence of DM in our cohort of NF-PNETs was 1.6 higher than that in the age and gender-adjusted general Israeli population (95 %CI: 1.197-2.212p = 0.03).

Conclusions

We found a high rate of impaired glucose metabolism, either DM or Pre-DM, in a large cohort of NF-PNETs. The high prevalence of diabetes/pre-diabetes was unrelated to obesity or tumor size. This observation should increase awareness of the presence of DM on presentation or during treatment of "NF"-PNETs.

Esophagogastroduodenal Findings in Patients with Intraductal Papillary Mucinous Neoplasms

The association between intraductal papillary mucinous neoplasms (IPMNs) and extra-pancreatic malignancies is controversial. This cross-sectional study compared esophagogastroduodenal findings in 340 IPMN patients to those of age- and gender-matched controls without known IPMNs who underwent esophagogastroduodenoscopies (EGDs) for similar clinical reasons. The presence of gastric and esophageal cancer, Barrett's esophagus, neuroendocrine tumors (NETs), gastrointestinal stromal tumors (GISTs), gastric adenomas, and ampullary tumors was assessed. The results showed that 4/340 (1.2%) of the IPMN patients had gastric cancer and 1/340 (0.3%) had esophageal cancer. The matched control group had a similar incidence of gastric cancer (5/340) (1.5%), with no esophageal cancer cases (p > 0.999). The overall incidence of other esophagogastroduodenal conditions did not significantly differ between the IPMN patients and the controls. However, the incidence of gastric cancer in the IPMN patients was higher than expected based on national cancer registry data (standardized incidence ratio of 31.39; p < 0.001; CI 8.38-78.76). In conclusion, IPMN patients have a significantly higher incidence of gastric cancer compared to the general population. However, the incidence of esophagogastroduodenal findings, including gastric and esophageal cancer, is similar between IPMN patients and those who undergo an EGD for similar clinical indications. Further research is needed to determine optimal surveillance strategies for IPMN patients regarding their risk of developing gastric cancer.

PD-1 Blockade Combined with Heated Intraperitoneal Chemotherapy Improves Outcome in Experimental Peritoneal Metastases from Colonic Origin in a Murine Model

BACKGROUND

Heated intraperitoneal chemotherapy (HIPEC) was shown to induce immunogenicity of peritoneal metastases from colorectal cancer (PM-CRC) by induction of immunogenic cell death. We aimed to explore whether the addition of a checkpoint inhibitor would augment the effect of HIPEC in an experimental murine model of PM-CRC.

METHODS

PM-CRC was established in C57BL mice by intraperitoneal inoculation of MC38 colon cancer cells. HIPEC was administered using the closed technique with mitomycin C (MMC). Clinical and immunological parameters were compared between animals treated with HIPEC alone and those treated with HIPEC + anti-programmed death receptor-1 (aPD-1).

RESULTS

MMC-based HIPEC increased the overall survival of animals compared with sham-treated animals (22.8; 95% confidence interval [CI] 21.14-24.53 vs. 18.9 days; 95% CI 17.6-20.3, p < 0.001). The extent of peritoneal disease as measured by the modified peritoneal carcinomatosis index was also reduced by HIPEC. This clinical benefit was accompanied by increased infiltration of CD8⁺, CD68⁺, and CD20⁺ cells into tumor metastases in HIPEC-treated animals compared with sham-treated animals. We identified heat shock protein (HSP) 90 as a potential immunogenic cell death protein whose expression is increased under HIPEC conditions (fold change: 2.37 ± 1.5 vs. 1 without HIPEC, p < 0.05). Combined HIPEC + PD-1 treatment ameliorated survival compared with HIPEC alone and sham treatment (24.66; 95% CI 20.13-29.2 vs. 19; 95% CI 15.85-22.14 and 14.33 days; 95% CI 9.6-19.04, respectively; p = 0.008). This clinical effect was accompanied by increased CD8⁺ tumor infiltration.

CONCLUSIONS

HIPEC induced the expression of immunogenic cell death signals that can support an anti-tumor immune response. This response can be further exploited by a checkpoint inhibitor.

The risk of PD-L1 expression misclassification in triple-negative breast cancer

Purpose

Stratification of patients with triple-negative breast cancer (TNBC) for anti-PD-L1 therapy is based on PD-L1 expression in tumor biopsies. This study sought to evaluate the risk of PD-L1 misclassification.

Methods

We conducted a high-resolution analysis on ten surgical specimens of TNBC. First, we determined PD-L1 expression pattern distribution via manual segmentation and measurement of 6666 microscopic clusters of positive PD-L1 immunohistochemical staining. Then, based on these results, we generated a computer model to calculate the effect of the positive PD-L1 fraction, aggregate size, and distribution of PD-L1 positive cells on the diagnostic accuracy.

Results

Our computer-based model showed that larger aggregates of PD-L1 positive cells and smaller biopsy size were associated with higher fraction of false results (P < 0.001, P < 0.001, respectively). Additionally, our model showed a significant increase in error rate when the fraction of PD-L1 expression was close to the cut-off (error rate of 12.1%, 0.84%, and 0.65% for PD-L1 positivity of 0.5–1.5%, ≤ 0.5% ,and ≥ 1.5%, respectively, P < 0.0001). Interestingly, false positive results were significantly higher than false negative results (0.51–22.62%, with an average of 6.31% versus 0.11–11.36% with an average of 1.58% for false positive and false negative results, respectively, P < 0.05). Furthermore, heterogeneous tumors with different aggregate sizes in the same tumor, were associated with increased rate of false results in comparison to homogenous tumors (P < 0.001).

Conclusion

Our model can be used to estimate the risk of PD-L1 misclassification in biopsies, with potential implications for treatment decisions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-022-06630-3.

ROS1-positive Inflammatory Myofibroblastic Tumor of the Small Bowel Causing Obstruction: A Case Report

Inflammatory Myofibroblastic Tumors (IMTs) are rare fibroblastic/myofibroblastic neoplasms that affect predominately pediatric patients and young adults. Almost half of the patients with IMTs have a chromosomal abnormality in the Anaplastic Lymphoma Kinase 1 gene on chromosome 2p23. Although these tumors occur primarily in the lung, lesions have been reported in a variety of intra-abdominal organs like the liver, spleen, and mesentery. Small bowel IMTs are particularly rare. IMTs generally pursue a benign clinical course, however intra-abdominal and retroperitoneal tumors have typically shown higher local recurrence and even distant metastases. The most common presenting symptoms of an intra-abdominal IMT are abdominal pain and change in bowel habits. Laboratory results are nonspecific and can include anemia and minor elevation of inflammatory markers like C-reactive protein. We report an unusual case of IMT in the small bowel causing the obstruction.

Lymph Node Metastases from Visceral Peritoneal Colorectal Metastases are Associated with Systemic Recurrence

BACKGROUND

Visceral peritoneal colorectal metastases (VPCMs) may further metastasize to lymph nodes that drain those organs. The rate of lymph node metastases (LNMs) from VPCMs and their clinical and prognostic significance are unknown.

METHODS

This study retrospectively analyzed the authors' institutional databases of 160 patients with peritoneal colorectal metastases who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Patients with LNM-VPCM (n = 12) were identified by pathologic reports, and both their short- and long-term outcomes were compared with those of patients without LNM-VPCM.

RESULTS

The clinical presentation and primary tumor pathologic characteristics did not differ between the two groups. The patients with LNM-VPCM had a higher tumor burden (measured by the peritoneal carcinomatosis index [PCI]) and visible remnant disease compared with those who had no LNM-VPI (10 vs 5.5 [p = 0.03] vs 33.3% vs 6.8% [p = 0.007], respectively). The postoperative outcomes also were comparable. The patients with LNM-VPCM had a shorter overall survival (OS) than those without LNM-VPCM (median OS, 22.5 months; 95% confidence interval [CI], 15.1-29.9 months vs 40.1 months; 95% CI, 38.1-42 months; p = 0.02). However, only tumor grade and PCI were predictors of OS in the multivariate analysis (hazard ratio [HR], 2.33 [p = 0.001]; 1.77 [p = 0.03], respectively). The study showed that LNM-VPCM was associated with systemic but not peritoneal recurrence compared with non-LNM-VPCM (81.8% vs 51.6% for systemic recurrence, respectively; p = 0.05).

CONCLUSION

The small distinct group of patients defined by LNM-VPCM were prone to systemic recurrence. Given its correlation with systemic recurrence, LNM-VPCM may indicate the need for adjuvant treatment.

Automatic ganglion cell detection for improving the efficiency and accuracy of hirschprung disease diagnosis

Histopathologic diagnosis of Hirschsprung's disease (HSCR) is time consuming and requires expertise. The use of artificial intelligence (AI) in digital pathology is actively researched and may improve the diagnosis of HSCR. The purpose of this research was to develop an algorithm capable of identifying ganglion cells in digital pathology slides and implement it as an assisting tool for the pathologist in the diagnosis of HSCR. Ninety five digital pathology slides were used for the construction and training of the algorithm. Fifty cases suspected for HSCR (727 slides) were used as a validation cohort. Image sets suspected to contain ganglion cells were chosen by the algorithm and then reviewed and scored by five pathologists, one HSCR expert and 4 non-experts. The algorithm was able to identify ganglion cells with 96% sensitivity and 99% specificity (in normal colon) as well as to correctly identify a case previously misdiagnosed as non-HSCR. The expert was able to achieve perfectly accurate diagnoses based solely on the images suggested by the algorithm, with over 95% time saved. Non-experts would require expert consultation in 20–58% of the cases to achieve similar results. The use of AI in the diagnosis of HSCR can greatly reduce the time and effort required for diagnosis and improve accuracy.

Protective Desmoplasia in Pancreatic Adenocarcinoma: High Vitamin D Receptor Expression and Collagen Content

BACKGROUND/AIM

Vitamin D receptor (VDR) has been shown to suppress desmoplasia in pancreatic ductal adenocarcinoma (PDAC). Our aim was to assess the clinical effects of VDR expression and its correlation with collagen content in the desmoplasia of PDAC patients.

PATIENTS AND METHODS

This is a retrospective analysis of 127 patients with peritumoral desmoplasia resected for PDAC. VDR expression and collagen content were assessed by immunohistochemistry and correlated with clinical outcome.

RESULTS

Patients were classified into those with high and those with low VDR expression. High VDR expression was associated with improved overall survival (OS) in localized disease (N0) (median= 33; 95%CI=26.4-39.6 vs. 18; 15.5-20.5 months, p=0.01). Patients with high vs. low collagen content had improved OS [34, (range=22.3-45.6 months) vs. 17, (range=14.4-19.6 months), p<0.001]. The number of VDR+ cells was the same for patients with either high or low collagen content.

CONCLUSION

Protective desmoplasia is associated with increased VDR expression and collagen content.

Laparoscopic sentinel lymph node dissection followed by open radical hysterectomy for early stage cervical cancer: A pilot study

OBJECTIVE

To propose a treatment algorithm, after the LACC trial, of laparoscopic sentinel lymph node biopsy with frozen section, followed by immediate open radical hysterectomy in node-negative cases, for early stage cervical cancer.

METHODS

We retrospectively collected all cases of cervical cancer that were surgically treated between 2019-2020. In all cases, surgery began with laparoscopic sentinel lymph node biopsy ± ovarian transposition. Node-negative cases continued with open radical hysterectomy. In node-positive cases, surgery was discontinued, sparing the patient a laparotomy incision.

RESULTS

Nine patients with cervical cancer were referred for surgery. Laparoscopic bilateral lymph node identification was achieved in all. In two cases, sentinel lymph nodes were positive for metastatic cancer and surgery was discontinued. For the other seven, node-negative patients, open radical hysterectomy was completed. Four patients had laparoscopic ovarian transposition. There were no cases where nodes were negative on frozen section but positive on final pathology.

CONCLUSION

Laparoscopic sentinel lymph node biopsy before open radical hysterectomy may spare a considerable number of laparotomies on the one hand and bi-modal treatment with surgery and radiation on the other, for node-positive patients. The oncological safety of this approach is yet to be determined.

Spatial heterogeneity of PD-L1 expression and the risk for misclassification of PD-L1 immunohistochemistry in non-small cell lung cancer

BACKGROUND

Intra-tumor heterogeneity for PD-L1 expression in non-small cell lung cancer (NSCLC) might lead to inaccurate stratification of patients to immunotherapy. The purpose of this research was to quantitate the effect of different factors on the risk of inaccurate diagnosis of PD-L1 expression.

METHODS

MATLAB software was used to model tumor with a different fraction, distribution and clustering of PD-L1 protein expression and their effect on false positive and negative diagnosis in subsets of the modeled tumor (representing biopsies). Additionally, we evaluated the agreement between PD-L1 status in random segments and whole slides of PD-L1 stained clinical NSCLC cases.

RESULTS

Our computer-based model showed a significant increase in error rate when the fraction of PD-L1 positive cells was closer to the cut-off value (error rate of 33.33 %, 0.45 % and 0.74 % for PD-L1 positivity in 40-60%, ≤20 % and ≥80 % of tumor cells, respectively, P < 0.0001). In addition, biopsy size showed negative correlation with error rate (P < 0.0001) and larger clusters of PD-L1 positive cells were associated with higher error rate (P < 0.0001). Analysis of the clinical samples supported those of the computer-based model with higher error rate in cases with positive PD-L1 expression closer to the cutoff value. Based on our computerized model and clinical analysis, we developed a model to predict error rate based on biopsy size and the fraction of PD-L1 positive cells in the biopsy.

CONCLUSION

Analysis of small biopsies for PD-L1 expression might be associated with significant error rate. The model presented can be used to identify cases with increased risk for error in whom interpretation of the test results should be made with caution.

SAT-180 Adrenocortical Carcinoma - A Tertiary Center’s Recent 5-Year Experience

BACKGROUND: Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with poor prognosis. The aim of this study was to characterize patients diagnosed with ACC at a single center between 2014-2019.

METHODS: We retrospectively reviewed data regarding demographics, tumor characteristics and functionality, treatment and survival.

RESULTS: The study cohort included 27 subjects (56% females), followed for 27±10.6 months. The mean age at diagnosis was 49.4±9 years. Co-morbidities at presentation included hypertension (63%), diabetes mellitus (22%) and dyslipidemia (26%). 74.1% of tumors were functioning – of which 85% were cortisol-secreting and 15% androgen-secreting. Aldosterone was secreted additionally in 15%. ENSAT stage at diagnosis was stage 1 in 15%, stage 2 in 35%, stage 3 in 12% and stage 4 in 38%. Eighty-nine % of patients underwent surgery. Treatment with mitotane was initiated in 82% of patients, reaching a mean maximal dose of 3.3 ±0.4 grams/day. Chemotherapy and/or radiation were given in 37% and 22%, respectively. Several patients (14.8%) had a second primary cancer, diagnosed before ACC in 75%. Progression was observed in 48% of patients, with a progression-free survival of 8.3±6.6 months. Thirty-five % of patients died during follow up, time to death was 12.8±0.4 months. Twenty two % of patients survived over 30 months after diagnosis. KI67 above 20% or stage above 2 negatively affected survival.

CONCLUSIONS: ACC remains a rare disease with a poor prognosis. However, it is a heterogeneous disease, with some patients achieving survival of over 30 months after diagnosis. Further characterization of this population may improve our understanding of the biology and treatment of this rare disease.

Traumatic Ulcerative Granuloma with Stromal Eosinophilia: CD30 analysis and clonality for T cell receptor gene re-arrangement

INTRODUCTION

Traumatic Ulcerative Granuloma with Stromal Eosinophilia (TUGSE) is a rare oral ulcerated lesion of uncertain etiology, showing eosinophil-rich granulation tissue, with occasional large atypical CD30 positive mononuclear cells. It had been suggested that it may represent an oral counterpart of cutaneous lymphomatoid papulosis, with a potential to evolve into CD30 + T cell lymphoma OBJECTIVES: To compare TUGSE and non-specific oral ulcers (NSU) clinically, histopathologically and by clonality analysis for T-cell receptor re-arrangement, aiming to determine whether TGUSE with atypical cells is a lymphomatous premalignant condition, and whether therapeutic approach should be radical or conservative.

MATERIALS AND METHODS

Retrospective archival analysis included 17 TUGSE and 8 NSU cases. Histopathological parameters included mean eosinophil number per high power field (HPF), presence of infiltration of deep soft tissues and presence of atypical cells. Immuno-morphometry comprised of the mean number of CD30+ atypical cells per HPF. T-cell receptor (TCR) gene rearrangement by polymerase chain reaction (PCR) was performed in all cases showing atypical cells. Clinical and follow up data were retrieved from files.

RESULTS

TUGSE showed a significantly higher mean eosinophil number/HPF in comparison to NSU (7.0 + 4.2 cells and 2.3 + 1.72, respectively; p < 0.001). Atypical cells were found in 9 (53%) cases of TUGSE and in only 1 (11%) case of NSU. CD30+ atypical cells were found in 7 (41%) cases of TUGSE and only in 1 (11%) case of NSU. Mean number of CD30+ cells/HPF was 0.23 + 0.19 (range 0 - 0.54 cells/HPF) for TUGSE. In the only NSU case with CD30+ cells, their density was 0.52/HPF. All lesions with atypical cells were polyclonal for TCR. All cases were self-limiting, with no recurrences, after 3-9 years (mean 4.6 years) follow up.

CONCLUSIONS

Analysis found no support to the suggestion that TUGSE with atypical cells represents the oral counterpart of lymphomatoid papulosis or predisposes the lesions for a hematolymphoid malignancy. Suggestions for radical therapeutic approach and long-term follow-up are probably unjustified, with no recurrences or malignancy recorded following conservative treatment alone for a period of up to 9 years of follow-up. Staining for CD30 and PCR for TCR gene rearrangement should be reserved only for rare cases with abundant large atypical cells and/or unusual clinical behavior.

A sorafenib-sparing effect in the treatment of thyroid carcinoma cells attained by co-treatment with a novel isoflavone derivative and 1,25 dihydroxyvitamin D3

BACKGROUND

Sorafenib improves progression-free survival in patients with progressive radioactive iodine-refractory differentiated thyroid carcinoma, but causes severe side effects. Estrogens may accelerate thyroid carcinoma cell growth. Our group recently reported that isoflavone derivative 7-(O)-carboxymethyl daidzein conjugated to N-t-boc-hexylenediamine (cD-tboc), a novel anti-estrogenic compound, retards the growth of both thyroid carcinoma cell lines and cultured human carcinoma cells. Vitamin D receptor (VDR) is expressed in malignant cells and responds to 1,25 dihydroxyvitamin D3 (1.25D) by decreased proliferative activity in vitro. The purpose of this study was to examine the effects of vitamin D metabolites (VDM) on the expression of estrogen receptors (ERs), VDR, and 1OHase mRNA, and to evaluate the inhibitory effect of low doses of sorafenib in combination with cDtboc and VDM on cell proliferation in cultured human papillary thyroid carcinoma (PTC).

METHODS

In 19 cultured PTC specimens and 19 normal thyroid specimens, harvested during thyroidectomies from the same patients, expression levels of ERα, ERβ, VDR, and 1 alpha-hydroxylase (1OHase) mRNA (by quantitative real-time PCR) were determined at baseline and after treatment with VMD. Cell proliferation was determined by measurement of ³[H] thymidine incorporation after treatment with sorafenib alone, sorafenib with added 1.25D or cD-tboc, and sorafenib with both 1.25D and cD-tboc added.

RESULTS

1,25D increased mRNA expression of all tested genes in the malignant and normal thyroid cells, while the ERα mRNA of the normal cells was unaffected. 1.25D dose-dependently inhibited cell proliferation in the malignant cells. The inhibitory effect of sorafenib on cell proliferation in the malignant cells was amplified after the addition of cDtboc and 1.25D, such that the maximal inhibition was not only greater, but also had been attained at a 10-fold lower concentration of sorafenib (20 μg/ml). This inhibition was similar to that of the generally used concentration of sorafenib (200 μg/ml) alone.

CONCLUSIONS

The demonstration that low concentrations of cDtboc and 1.25D markedly amplify the inhibitory effect of sorafenib on the growth of human PTC supports the use of a 10-fold lower concentration of sorafenib. The findings may promote a new combination treatment for progressive radioactive iodine-refractory PTC.

Vitamin D receptor expression is linked to potential markers of human thyroid papillary carcinoma

Genes regulated cell-cell and cell-matrix adhesion and degradation of the extracellular matrix (ECM) have been screened as potential markers of malignant thyroid nodules. The mRNA expression levels of two of them, the ECM protein-1 (ECM1) and the type II transmembrane serine protease-4 (TMPRSS4), were shown to be an independent predictor of an existing thyroid carcinoma. The vitamin D receptor (VDR) is expressed in epithelial cells of the normal thyroid gland, as well as in malignant dividing cells, which respond to the active metabolite of vitamin D by decreased proliferative activity in vitro. We evaluated the relationship between mRNA gene expressions of TMPRSS4, ECM1 and VDR in 21 papillary thyroid carcinoma samples and compared it to 21 normal thyroid tissues from the same patients. Gene expression was considered as up- or down-regulated if it varied by more or less than 2-fold in the cancer tissue relative to the normal thyroid tissue (Ca/N) from the same patient. We found an overall significant adjusted correlation between the mRNA expression ratio (ExR) of VDR and that of ECM1 in Ca/N thyroid tissue (R=0.648, P<0.001). There was a high ExR of VDR between Ca/N thyroid tissue from the same patient (3.06±2.9), which also exhibited a high Ca/N ExR of ECM1 and/or of TMPRSS4 (>2, P=0.05).The finding that increased VDR expression in human thyroid cancer cells is often linked to increased ECM1 and/or TPMRSS4 expression warrants further investigation into the potential role of vitamin D analogs in thyroid carcinoma.