[Current WHO classification (2022) of neuroendocrine neoplasms]. / Aktuelle WHO-Klassifikation (2022) neuroendokriner Neoplasien.

CLINICAL ISSUE: After the first description of the "carcinoid tumors" by the pathologist Siegfried Oberndorfer in Munich, the classification system of neuroendocrine neoplasms (NENs) is still a challenge and an evolving concept. METHODICAL INNOVATIONS: The new WHO classification system proposed a framework for universal classification. ACHIEVEMENTS: The new WHO classification system recognizes two distinct families distinguished by genetic, morphology and clinical behaviour: Well differentiated NENs are defined as neuroendocrine tumor (NET G1, G2, G3), while poorly differentiated ones are defined as neuroendocrine carcinoma (NEC, G3) and further subdivided into small and large cell carcinoma. All NENs are characterized by the expression of synaptophysin and chromogranin A, Ki-67 and morphology. MOLECULAR PATHOLOGY: The morphological NEN dichotomy is supported by genetic alterations. NECs show TP53 and RB1 alterations that are absent in NETs and are therefore useful for differentiating between NETs and NECs. PRACTICAL RECOMMENDATIONS: All NENs are divided into well-differentiated neuroendocrine tumor (NET G1, G2, G3) or poorly differentiated neuroendocrine carcinoma (NEC, G3). They are categorized by morphology, mitotic count and immunohistochemistry with synaptophysin, chromogranin and Ki-67.

Opposing effects of cannabidiol in patient-derived neuroendocrine tumor, pheochromocytoma/paraganglioma primary cultures.

CONTEXT: Treatment options for advanced neuroendocrine tumors (NETs), pheochromocytomas and paragangliomas (together PPGLs) are still limited. In recent years, anti-tumor effects of cannabinoids have been reported; however, there are only very limited data available in NETs or PPGLs. OBJECTIVE: Investigation of the effects of cannabidiol (CBD) on patient-derived human NET/PPGL primary cultures and on NET/PPGL cell lines. METHODS: We established primary cultures derived from 46 different patients with PPGLs (n = 35) or NETs (n = 11) who underwent tumor resection at two centers. Treatment of patient primary cultures with clinically relevant doses (5 µM) and slightly higher doses (10 µM) of CBD was performed. RESULTS: We found opposing effects of 5 µM CBD: significant anti-tumor effects in 5/35 (14%) and significant tumor-promoting effects in 6/35 (17%) of PPGL primary cultures. In terms of anti-tumor effects, cluster 2-related PPGLs showed significantly stronger responsivity to CBD compared to cluster 1-related PPGLs (p = 0.042). Of the cluster 2-related tumors, NF1 PPGLs showed strongest responsivity (4/5 PPGL primary cultures with a significant decrease in cell viability were NF1-mutated). We also found opposing effects of 10 µM CBD in PPGLs and NETs: significant anti-tumor effects in 9/33 of PPGL (27%) and 3/11 of NET (27%) primary cultures, significant tumor-promoting effects in 6/33 of PPGL (18%) and 2/11 of NET (18%) primary cultures. CONCLUSIONS: We suggest a potential novel treatment option for some NETs/PPGLs, but also provide evidence for caution when applying cannabinoids as supportive therapy for pain or appetite management to cancer patients, and possibly as health supplements.

The Effect of chemo- and radiotherapy on tumor necrosis in soft tissue sarcoma- does it influence prognosis?

BACKGROUND: Soft tissue sarcomas (STSs) are a heterogeneous group of tumors. Wide surgical resection is standard, often combined with neoadjuvant chemotherapy, radiotherapy, or both. Studies have shown the predictive value of tumor necrosis in bone sarcoma (BS); however, the role of necrosis in STS after neoadjuvant therapies is still unclear. This study aimed to investigate the role of chemo- and radiotherapy in the formation of tumor necrosis and to evaluate the influence of tumor necrosis on overall survival and local recurrence-free survival. Data from BS patients and patients who did not receive neoadjuvant therapy were compared. METHODS: A total of 779 patients with STS or BS were treated surgically. In all patients, tumor-specific factors such as type, size, or grading and the type of adjuvant therapy were documented. Local recurrence (LR), the diagnosis of metastatic disease, and survival during follow-up were evaluated. RESULTS: A total of 565 patients with STS and 214 with BS were investigated. In STS, 24.1% G1 lesions, 34.1% G2 lesions, and 41.8% G3 lesions were observed. Two hundred twenty-four of the patients with STS and neoadjuvant therapy had either radiotherapy (RTx) (n = 80), chemotherapy (CTx) (n = 93), or both (n = 51). Three hundred forty-one had no neoadjuvant therapy at all. In STS, tumor necrosis after neoadjuvant treatment was significantly higher (53.5%) than in patients without neoadjuvant therapy (15.7%) (p < 0.001). Patients with combined neoadjuvant chemo-/radiotherapy had substantially higher tumor necrosis than those with radiotherapy alone (p = 0.032). There was no difference in tumor necrosis in patients with combined chemo-/radiotherapy and chemotherapy alone (p = 0.4). The mean overall survival for patients with STS was 34.7 months. Tumor necrosis did not influence survival in a subgroup of G2/3 patients. In STS with no neoadjuvant therapy and grading of G2/3, the correlation between necrosis and overall survival was significant (p = 0.0248). There was no significant correlation between local recurrence (LR) and necrosis. CONCLUSION: STS shows a broad spectrum of necrosis even without neoadjuvant chemo- or radiotherapy. After CTx or/and RTx necrosis is enhanced and is significantly pronounced with a combination of both. There is a trend toward higher necrosis with CTx than with RTx. Grading substantially influences the necrosis rate, but necrosis in soft-tissue sarcoma following neoadjuvant therapy does not correlate with better survival or a lower local recurrence rate, as in bone sarcomas.

Differentiation of benign and metastatic lymph nodes in soft tissue sarcoma.

Lymph node metastasis (LNM) occurs in less than 5% of soft tissue sarcoma (STS) patients and indicates an aggressive course of disease. Suspicious lymph nodes (LN) in staging imaging are a frequent topic of discussion in multidisciplinary tumor boards. Predictive markers are needed to facilitate stratification and improve treatment of STS patients. In this study, 56 STS patients with radiologically suspicious and subsequently histologically examined LN were reviewed. Patients with benign (n = 26) and metastatic (n = 30) LN were analyzed with regard to clinical, laboratory and imaging parameters. Patients with LNM exhibited significantly larger short axis diameter (SAD) and long axis diameter (LAD) vs. patients with benign LN (median 22.5 vs. 14 mm, p < 0.001 and median 29.5 vs. 21 mm, p = 0.003, respectively). Furthermore, the presence of central necrosis and high maximal standardized uptake value (SUVmax) in FDG-PET-CT scans were significantly associated with LNM (60 vs. 11.5% of patients, p < 0.001 and median 8.59 vs. 3.96, p = 0.013, respectively). With systemic therapy, a slight median size regression over time was observed in both metastatic and benign LN. Serum LDH and CRP levels were significantly higher in patients with LNM (median 247 vs. 187.5U/L, p = 0.005 and 1.5 vs. 0.55 mg/dL, p = 0.039, respectively). This study shows significant associations between LNM and imaging features as well as laboratory parameters of STS patients. The largest SAD, SUVmax in FDG-PET-CT scan, the presence of central necrosis, and high serum LDH level are the most important parameters to distinguish benign from metastatic LNs.

Unilateral Primary Aldosteronism: Long-Term Disease Recurrence After Adrenalectomy.

BACKGROUND: Primary aldosteronism (PA) is frequently caused by a unilateral aldosterone-producing adenoma with a PA-driver mutation. Unilateral adrenalectomy has a high probability of short-term biochemical remission, but long-term postsurgical outcomes are relatively undefined. Our objective was to investigate the incidence of long-term recurrence of PA in individuals with postsurgical short-term biochemical remission. METHODS: Adrenalectomized patients for unilateral PA were included from a single referral center. Histopathology and outcomes were assessed according to international histopathology of unilateral primary aldosteronism and PASO (Primary Aldosteronism Surgical Outcome) consensuses. Genotyping was performed using CYP11B2 (aldosterone synthase)-guided sequencing. RESULTS: Classical adrenal histopathology, exemplified by a solitary aldosterone-producing adenoma, was observed in 78% of 90 adrenals, compared with 22% with nonclassical histopathology. The classical group displayed higher aldosterone-to-renin ratios (P=0.013) and lower contralateral ratios (P=0.008). Outcome assessments at both short (12 months [7; 12]) and long (89 months [48; 124]) terms were available for 57 patients. At short-term assessment, 53 (93%) displayed complete biochemical success (43 classical and 10 nonclassical), but long-term assessment demonstrated biochemical PA recurrence in 12 (23%) with an overrepresentation of the nonclassical histopathology (6 [60%] of 10 nonclassical histopathology versus 6 [14%] of 43 classical histopathology; P=0.005). PA-driver mutations were identified in 97% of 64 aldosterone-producing adenomas; there was no association of the aldosterone-producing adenoma genotype with PA recurrence. CONCLUSIONS: A substantial proportion of individuals display postsurgical biochemical recurrence of PA, which is related to the histopathology of the resected adrenal gland. These findings emphasize the role of histopathology and the requirement for continued outcome assessment in the management of surgically treated patients for PA.

Refusal of Adjuvant Therapies and Its Impact on Local Control and Survival in Patients with Bone and Soft Tissue Sarcomas of the Extremities and Trunk.

BACKGROUND: In soft tissue or bone sarcomas, multimodal therapeutic concepts represent the standard of care. Some patients reject the therapeutic recommendations due to several reasons. The aim of this study was to assess the impact of that rejection on both prognosis and local recurrence. METHODS: Between 2012 and 2019, a total of 828 sarcoma patients were surgically treated. Chemotherapy was scheduled as a neoadjuvant, and adjuvant multi-agent therapy was performed following recommendations from an interdisciplinary tumor board. Radiotherapy, if deemed appropriate, was administered either in a neoadjuvant or an adjuvant manner. The recommended type of therapy, patient compliance, and the reasons for refusal were documented. Follow-ups included local recurrences, diagnosis of metastatic disease, and patient mortality. RESULTS: Radiotherapy was recommended in 407 (49%) patients. A total of 40 (10%) individuals did not receive radiation. A reduction in overall survival and local recurrence-free survival was evident in those patients who declined radiotherapy. Chemotherapy was advised for 334 (40%) patients, 250 (75%) of whom did receive all recommended cycles. A total of 25 (7%) individuals did receive a partial course while 59 (18%) did not receive any recommended chemotherapy. Overall survival and local recurrence-free survival were reduced in patients refusing chemotherapy. Overall survival was worst for the group of patients who received no chemotherapy due to medical reasons. Refusing chemotherapy for non-medical reasons was seen in 8.8% of patients, and refusal of radiotherapy for non-medical reasons was seen in 4.7% of patients. CONCLUSIONS: Divergence from the advised treatment modalities significantly impacted overall survival and local recurrence-free survival across both treatment modalities. There is an imperative need for enhanced physician-patient communication. Reducing treatment times, as achieved with hypofractionated radiotherapy and with therapy in a high-volume sarcoma center, might also have a positive effect on complying with the treatment recommendations.

High-Dose Rate Brachytherapy Combined with PD-1 Blockade as a Treatment for Metastatic Adrenocortical Carcinoma - A Single Center Case Series.

The response rate of advanced adrenocortical carcinoma (ACC) to standard chemotherapy with mitotane and etoposide/doxorubicin/cisplatin (EDP-M) is unsatisfactory, and benefit is frequently short lived. Immune checkpoint inhibitors (CPI) have been examined in patient's refractory to EDP-M, but objective response rates are only approximately 15%. High-dose rate brachytherapy (HDR-BT) is a catheter-based internal radiotherapy and expected to favorably combine with immunotherapies. Here we describe three cases of patients with advanced ACC who were treated with HDR-BT and the CPI pembrolizumab. None of the tumors were positive for established response markers to CPI. All patients were female, had progressed on EDP-M and received external beam radiation therapy for metastatic ACC. Pembrolizumab was initiated 7 or 23 months after brachytherapy in two cases and prior to brachytherapy in one case. Best response of lesions treated with brachytherapy was complete (n=2) or partial response (n=1) that was ongoing at last follow up after 23, 45 and 4 months, respectively. Considering all sites of tumor, response was complete and partial remission in the two patients with brachytherapy prior to pembrolizumab. The third patient developed progressive disease with severe Cushing's syndrome and died due to COVID-19. Immune-related adverse events of colitis (grade 3), gastroduodenitis (grade 3), pneumonitis (grade 2) and thyroiditis (grade 1) occurred in the two patients with systemic response. HDR-BT controlled metastases locally. Sequential combination with CPI therapy may enhance an abscopal antitumoral effect in non-irradiated metastases in ACC. Systematic studies are required to confirm this preliminary experience and to understand underlying mechanisms.

Colitis induced by IL-17A-inhibitors.

BACKGROUND: Interleukin (IL)-17A is essential for intestinal mucosal integrity, contributing to the prevention of detrimental immunity such as infectious colitis and inflammatory bowel disease (IBD). Indeed, neutralization of IL-17A has been abandoned as a therapeutic principle in IBD because of increased disease activity. However, it is controversial whether IL-17A inhibitors increase the risk of developing colitis in patients who do not have underlying IBD. Here, we present two cases of different forms of colitis that occurred during treatment with two IL-17A inhibitors, secukinumab and ixekizumab. CASE PRESENTATIONS: We report the case of a 35-year-old female with SAPHO (synovitis-acne-pustulosis-hyperostosis-osteitis) syndrome who was admitted due to severe colitis with bloody diarrhea, fever, abdominal pain and weight loss after receiving secukinumab for 3 months as well as the case of a 41-year-old male with psoriatic arthritis who presented himself to the outpatient clinic with bloody stools, abdominal pain and nausea 5 months after changing his therapy from secukinumab to ixekizumab. In both patients, treatment with IL-17A-inhibitors was stopped and tumor necrosis factor inhibitors were started. Both patients recovered, are clinically stable and show no more signs of active colitis. CONCLUSION: The role of IL-17A inhibitors in the pathogenesis of infectious colitis and new-onset IBD is not fully understood and requires further research. Patients receiving IL-17A-inhibitor therapy should be carefully screened and notified of the possible side effects.

Implementing precision oncology for sarcoma patients: the CCCLMUmolecular tumor board experience.

PURPOSE: Due to poor outcomes and limited treatment options, patients with advanced bone and soft tissue sarcomas (BS/STS) may undergo comprehensive molecular profiling of tumor samples to identify possible therapeutic targets. The aim of this study was to determine the impact of routine molecular profiling in the setting of a dedicated precision oncology program in patients with BS/STS in a German large-volume sarcoma center. METHODS: 92 BS/STS patients who received comprehensive genomic profiling (CGP) and were subsequently discussed in our molecular tumor board (MTB) between 2016 and 2022 were included. Patient records were retrospectively reviewed, and the clinical impact of NGS-related findings was analyzed. RESULTS: 89.1% of patients had received at least one treatment line before NGS testing. At least one molecular alteration was found in 71 patients (82.6%). The most common alterations were mutations in TP53 (23.3% of patients), followed by PIK3CA and MDM2 mutations (9.3% each). Druggable alterations were identified, and treatment recommended in 32 patients (37.2%). Of those patients with actionable alterations, ten patients (31.2%) received personalized treatment and six patients did benefit from molecular-based therapy in terms of a progression-free survival ratio (PFSr) > 1.3. CONCLUSION: Our single-center experience shows an increasing uptake of next-generation sequencing (NGS) and highlights current challenges of implementing precision oncology in the management of patients with BS/STS. A relevant number of patients were diagnosed with clinically actionable alterations. Our results highlight the potential benefit of NGS in patients with rare cancers and currently limited therapeutic options.

NTRK fusion events and targeted treatment of advanced radioiodine refractory thyroid cancer.

PURPOSE: Pathogenic fusion events involving neurotrophic receptor tyrosine kinase (NTRK) have been described in ~ 2% of differentiated thyroid cancer (DTC). The selective tropomyosin receptor kinase (TRK) inhibitors entrectinib and larotrectinib have been approved in a tumor agnostic manner based on phase 1/2 clinical trials. In a real-world setting at five referral centers, we aimed to describe the prevalence of NTRK gene fusions and the efficacy and safety of TRK inhibitor treatment for non-medullary, advanced thyroid cancer (TC). METHODS: A total of 184 TC patients with testing for NTRK gene fusions were included. Progression-free survival (PFS) and overall survival (OS) probabilities were estimated using the Kaplan-Meier method in six patients with NTRK fusion-positive TC who underwent TRK inhibitor therapy. RESULTS: 8/184 (4%) patients harbored NTRK gene fusions. Six patients with radioiodine (RAI)-refractory TC harboring NTRK1 (n = 4) and NTRK3 (n = 2) gene fusions were treated with larotrectinib. Five patients (83%) had received ≥ 1 prior systemic therapy and one patient did not receive prior systemic therapy. All patients had morphologically progressive disease before treatment initiation. Objective response rate was 83%, including two complete remissions. Median PFS from start of TRK inhibitor treatment was 23 months (95% confidence interval [CI], 0-57.4) and median OS was not reached (NR) (95% CI, NR). Adverse events were of grade 1-3. CONCLUSION: The prevalence of NTRK gene fusions in our cohort of RAI-refractory TC is slightly higher than reported for all TC patients. Larotrectinib is an effective treatment option in the majority of NTRK gene fusion-positive advanced TC patients after prior systemic treatment and has a favorable safety profile.

TIM-3 Qualifies as a Potential Immunotherapeutic Target in Specific Subsets of Patients with High-Risk Soft Tissue Sarcomas (HR-STS).

(1) Background: The expression of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), an immune checkpoint receptor on T cells, has been associated with dismal outcomes and advanced tumor stages in various solid tumors. The blockade of TIM-3 is currently under examination in several clinical trials. This study examines TIM-3 expression in high-risk soft tissue sarcomas (HR-STS). (2) Methods: Tumor cell expression of TIM-3 on protein level was analyzed in pre-treatment biopsies of patients with HR-STS. TIM-3 expression was correlated with clinicopathological parameters including tumor-infiltrating lymphocyte (TIL) counts, programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PDL-1) expression in patients with HR-STS. Survival dependent on the expression of TIM-3 was analyzed. (3) Results: TIM-3 expression was observed in 101 (56%) out of 179 pre-treatment biopsies of patients with HR-STS. TIM-3 expression was significantly more often observed in undifferentiated pleomorphic sarcomas (UPS) compared to other histological subtypes (p < 0.001), high TIL counts (p < 0.001), and high PD-1 (p < 0.001) and PD-L1 expression (p < 0.001). TIM-3 expression did not have a prognostic impact on survival in patients with HR-STS. (4) Conclusions: This is the first study to demonstrate a significant tumor cell expression of TIM-3 in specific subsets of patients with HR-STS. TIM-3 qualifies as a potential immunotherapeutic target in HR-STS.

The Novel Monoclonal IgG1-Antibody AB90-E8 as a Diagnostic Tool to Rapidly Distinguish Aspergillus fumigatus from Other Human Pathogenic Aspergillus Species.

In most cases, invasive aspergillosis (IA) is caused by A. fumigatus, though infections with other Aspergillus spp. with lower susceptibilities to amphotericin B (AmB) gain ground. A. terreus, for instance, is the second leading cause of IA in humans and of serious concern because of its high propensity to disseminate and its in vitro and in vivo resistance to AmB. An early differentiation between A. fumigatus and non-A. fumigatus infections could swiftly recognize a potentially ineffective treatment with AmB and lead to the lifesaving change to a more appropriate drug regime in high-risk patients. In this study, we present the characteristics of the monoclonal IgG1-antibody AB90-E8 that specifically recognizes a surface antigen of A. fumigatus and the closely related, but not human pathogenic A. fischeri. We show immunostainings on fresh frozen sections as well as on incipient mycelium picked from agar plates with tweezers or by using the expeditious tape mount technique. All three methods have a time advantage over the common procedures currently used in the routine diagnosis of IA and outline the potential of AB90-E8 as a rapid diagnostic tool.

Diagnostic accuracy of biopsy after neoadjuvant treatment for well-differentiated and dedifferentiated retroperitoneal liposarcoma.

PURPOSE: Accurate histopathological grading of percutaneous biopsies is essential to guide adequate management of patients with suspected retroperitoneal liposarcoma. In this regard, however, limited reliability has been described. Therefore, we conducted a retrospective study to assess the diagnostic accuracy in retroperitoneal soft tissue sarcomas and simultaneously investigate its impact on patients' survival. MATERIALS AND METHODS: Reports of an interdisciplinary sarcoma tumor board between 2012 and 2022 were systematically screened for patients with well-differentiated (WDLPS) and dedifferentiated retroperitoneal liposarcoma (DDLPS). Histopathological grading on pre-operative biopsy was correlated with corresponding postoperative histology. Additionally, patients' survival outcomes were examined. All analyses were performed in two subgroups: patients with primary surgery and patients with neoadjuvant treatment. RESULTS: A total of 82 patients met our inclusion criteria. Diagnostic accuracy of patients who underwent upfront resection (n = 32) was significantly inferior to patients with neoadjuvant treatment (n = 50) (66% versus 97% for WDLPS, p < 0.001; 59% versus 97% for DDLPS, p < 0.001). For patients with primary surgery, histopathological grading on biopsy and surgery was concordant in only 47% of cases. Sensitivity for detecting WDLPS was higher than for DDLPS (70% versus 41%). Higher histopathological grading in surgical specimens correlated with worse survival outcomes (p = 0.01). CONCLUSION: Histopathological grading of RPS may no longer be reliable after neoadjuvant treatment. The true accuracy of the percutaneous biopsy may need to be studied in patients who do not receive neoadjuvant treatment. Future biopsy strategies should aim to improve identification of DDLPS to inform patient management.

Comparison of somatostatin receptor expression in patients with neuroendocrine tumours with and without somatostatin analogue treatment imaged with [18F]SiTATE.

Purpose: Somatostatin analogues (SSA) are frequently used in the treatment of neuroendocrine tumours. Recently, [18F]SiTATE entered the field of somatostatin receptor (SSR) positron emission tomography (PET)/computed tomography (CT) imaging. The purpose of this study was to compare the SSR-expression of differentiated gastroentero-pancreatic neuroendocrine tumours (GEP-NET) measured by [18F]SiTATE-PET/CT in patients with and without previous treatment with long-acting SSAs to evaluate if SSA treatment needs to be paused prior to [18F]SiTATE-PET/CT. Methods: 77 patients were examined with standardised [18F]SiTATE-PET/CT within clinical routine: 40 patients with long-acting SSAs up to 28 days prior to PET/CT examination and 37 patients without pre-treatment with SSAs. Maximum and mean standardized uptake values (SUVmax and SUVmean) of tumours and metastases (liver, lymphnode, mesenteric/peritoneal and bones) as well as representative background tissues (liver, spleen, adrenal gland, blood pool, small intestine, lung, bone) were measured, SUV ratios (SUVR) were calculated between tumours/metastases and liver, likewise between tumours/metastases and corresponding specific background, and compared between the two groups. Results: SUVmean of liver (5.4 ± 1.5 vs. 6.8 ± 1.8) and spleen (17.5 ± 6.8 vs. 36.7 ± 10.3) were significantly lower (p < 0.001) and SUVmean of blood pool (1.7 ± 0.6 vs. 1.3 ± 0.3) was significantly higher (p < 0.001) in patients with SSA pre-treatment compared to patients without. No significant differences between tumour-to-liver and specific tumour-to-background SUVRs were observed between both groups (all p > 0.05). Conclusion: In patients previously treated with SSAs, a significantly lower SSR expression ([18F]SiTATE uptake) in normal liver and spleen tissue was observed, as previously reported for 68Ga-labelled SSAs, without significant reduction of tumour-to-background contrast. Therefore, there is no evidence that SSA treatment needs to be paused prior to [18F]SiTATE-PET/CT.

Case report: Extended Isolated Stopflow Limb Infusion (EISLI) for highly malignant osteosarcoma - complete pathological tumor remission and implantation of a knee joint prosthesis.

INTRODUCTION AND IMPORTANCE: An 18-year old osteosarcoma patient with a huge tumor mass at the distal femur and inguinal metastases was treated with the intention to preserve the leg and additionally treat the pelvic metastases locally. Therefore we modulated the technique of isolated limb perfusion. CASE PRESENTATION: Isolated Limb Perfusion was performed as an Extended Isolated Limb Stop-Flow Infusion (EISLI) where the pelvis was included into the perfusion bed. Balloon catheters were placed in the arterial and venous bifurcation in the pelvis. For increasing the drug concentration at the tumor site, an angiographic catheter was placed arterially with the tip right in front of the tumor region. A Stop-Flow phase before the perfusion phase was applied. CLINICAL DISCUSSION: After 4 cycles of EISLI the lesions in the pelvis disappeared and surgical resection of the tumor and implantation of an endoprosthesis was possible and successful. Histopathological findings showed no vital cells in the resected tumor region. Currently the patient is tumor free and does not show recurrence or pulmonal metastases for 18 months after the last induction treatment cycle. CONCLUSION: With EISLI the inclusion of the pelvis is possible during isolated limb perfusion. In addition with low total dosages EISLI enabled drug concentrations many times higher at the tumor site than possible during systemic chemotherapy or standard isolated limb perfusion. It is a technique that allows limb preservation and treatment of positive lymphnodes in the groin. Quality of life is maintained during the Regional Chemotherapy (RCT).

GATA4 and GATA6 loss-of-expression is associated with extinction of the classical programme and poor outcome in pancreatic ductal adenocarcinoma.

OBJECTIVE: GATA6 is a key regulator of the classical phenotype in pancreatic ductal adenocarcinoma (PDAC). Low GATA6 expression associates with poor patient outcome. GATA4 is the second most expressed GATA factor in the pancreas. We assessed whether, and how, GATA4 contributes to PDAC phenotype and analysed the association of expression with outcome and response to chemotherapy. DESIGN: We analysed PDAC transcriptomic data, stratifying cases according to GATA4 and GATA6 expression and identified differentially expressed genes and pathways. The genome-wide distribution of GATA4 was assessed, as well as the effects of GATA4 knockdown. A multicentre tissue microarray study to assess GATA4 and GATA6 expression in samples (n=745) from patients with resectable was performed. GATA4 and GATA6 levels were dichotomised into high/low categorical variables; association with outcome was assessed using univariable and multivariable Cox regression models. RESULTS: GATA4 messenger RNA is enriched in classical, compared with basal-like tumours. We classified samples in 4 groups as high/low for GATA4 and GATA6. Reduced expression of GATA4 had a minor transcriptional impact but low expression of GATA4 enhanced the effects of GATA6 low expression. GATA4 and GATA6 display a partially overlapping genome-wide distribution, mainly at promoters. Reduced expression of both proteins in tumours was associated with the worst patient survival. GATA4 and GATA6 expression significantly decreased in metastases and negatively correlated with basal markers. CONCLUSIONS: GATA4 and GATA6 cooperate to maintain the classical phenotype. Our findings provide compelling rationale to assess their expression as biomarkers of poor prognosis and therapeutic response.

Immuno-histochemical correlation of fibrosis-related markers with the desmoplastic reaction of the mesentery in small intestine neuroendocrine neoplasms.

INTRODUCTION: Small intestine neuroendocrine neoplasms (siNENs) will attain more importance due to their increasing incidence. Moreover, siNENs might lead to a desmoplastic reaction (DR) of the mesentery causing severe complications and deteriorating prognosis. The expression of fibrosis-related proteins appears to be the key mechanisms for the development of this desmoplastic reaction. Therefore, this study aimed to investigate the association of the desmoplastic mesentery with specific fibrosis-related protein expression levels. MATERIALS AND METHODS: By immunohistochemistry, the protein expression levels of four fibrosis-related markers (APLP2, BNIP3L, CD59, DKK3) were investigated in primary tumors of 128 siNENs. The expression levels were correlated with the presence of a desmoplastic reaction and clinico-pathological parameters. RESULTS: In the primary tumor, APLP2, BNIP3L, CD59 and DKK3 were highly expressed in 29.7% (n = 38), 64.9% (n = 83), 92.2% (n = 118) and 80.5% (n = 103), respectively. There was no significant correlation of a single marker or the complete marker panel to the manifestation of a desmoplastic mesentery. The desmoplastic mesentery was significantly associated with clinical symptoms, such as flushing and diarrhea. However, neither the fibrosis-related marker panel nor single marker expressions were associated with clinical symptoms. DISCUSSION: The expression rates of four fibrosis-related markers in the primary tumor display a distinct pattern. However, the expression patterns are not associated with desmoplastic altered mesenteric lymph node metastases and the expression patterns did not correlate with prognosis. These findings suggest alternative mechanisms being responsible for the desmoplastic reaction.

Heterogeneous molecular behavior in liver tumors (HCC and CCA) of two patients with acute intermittent porphyria.

INTRODUCTION: Acute intermittent porphyria (AIP) is a very rare (orphan) metabolic disorder of porphyrin biosynthesis which is characterized by elevated plasma and urine levels of 5-aminolevulinic acid (5-ALA) and porphobilinogen (PBG). Patients with this disorder which is caused by a germline mutation of the hydroxymethylbilan-synthase (HMBS)-gene have a high risk of primary liver cancer which may be determined by disease activity. The exact mechanism of carcinogenesis of this rare tumor is unknown, however. MATERIALS AND METHODS: We analyzed paraffin-embedded formalin-fixed liver tumor and normal liver specimens of two female AIP patients treated at the Munich EPNET center. One patient had developed hepatocellular carcinoma (HCC), the other intrahepatic cholangiocarcinoma (CCA). Since biallelic inactivation of HMBS had been observed in one study, we used Sanger and next-generation sequencing with a 8 gene porphyria panel plus 6 potential modifier loci to search for mutations in DNA extractions. RESULTS: In the patient with the HCC, we found a second inactivating mutation in the HMBS gene in the tumor but not in the adjacent normal liver tissue. No mutation could be found in the liver tissues of the patient with CCA, however. CONCLUSIONS: Biallelic inactivation of HMBS or protoporphyrinogen-oxidase (PPOX), another enzyme of porphyrin biosynthesis, has been observed in patients with acute porphyrias and liver tumors. We could confirm this in our patient with HCC with a mutation in HMBS but not in the one with CCA. Since 5-ALA can be converted into carcinogenic substances such as 4,5-dioxovaleric acid (DOVA) or 3,6-dihydropyrazine-2,5-dipropanoic acid (= cyclic dimerization product of 5-ALA), local production of these metabolites in hepatic areas with complete loss of HMBS activity may contribute to liver carcinogenesis.

Treatment of metastatic alveolar soft part sarcoma with axitinib and pembrolizumab in an 80-year-old patient with a history of autoimmune disorders.

Alveolar soft part sarcoma (ASPS) is a rare malignancy with low sensitivity to chemotherapy. While localized ASPS has a very good prognosis after resection, the 5-year overall survival rate drops substantially in metastatic disease. We report the case of an 80-year-old male patient with ASPS of the left elbow and metastasis to the lung, lymph nodes and peritoneum. After weighing the benefits and risks, systemic treatment with the anti-PD-1 checkpoint inhibitor pembrolizumab combined with the vascular endothelial growth factor receptor tyrosinkinase inhibitor axitinib was initiated in this patient with a history of psoriasis and Crohn's disease. After only two cycles of therapy, a significant size reduction of the nodal cervical metastasis became apparent. A partial response of all metastases was then confirmed in the first computed tomography restaging. So far, side effects have remained manageable, especially with regard to the development or worsening of autoimmune adverse events. The patient continued to have a high quality of life, while also remaining in ongoing partial response for 15 months at the time of submission. While sarcomas generally have low sensitivity to immunotherapies, ASPS is an exception, and checkpoint inhibition is an integral part of its systemic therapy.

Thyroidal Angiotensin-Converting Enzyme 2 Protein Expression and Thyroid Function Tests in Patients with COVID-19: Results from a Retrospective Case Series and a Prospective Cohort Study.

Background: Infection with SARS-CoV-2 has initially been known as a respiratory disease but in the course of the pandemic the understanding has emerged that severity is owing to fatal inflammatory responses apart from lung injury. In this context, endocrine disorders such as thyroiditis as well as pituitary dysfunction in addition to nonthyroidal illness syndrome have been described. Furthermore, angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 cell receptor, has been detected in most endocrine tissues, including the thyroid gland. Objective: To evaluate histopathologic changes and compare thyroidal ACE2 protein expression in thyroid tissue from patients who died from severe COVID-19 with thyroid tissue from patients without SARS-CoV-2 infection in a retrospective case series. Furthermore, to assess and compare alterations in thyroid function tests (TFTs) between patients with or without SARS-CoV-2 infection as well as association of TFTs with the severity of the disease in a prospective cohort study. Methods: Thyroid tissue of deceased COVID-19 patients (n = 23) was analyzed for histopathology and ACE2 expression by immunohistochemical staining. A total of 153 patients with confirmed SARS-CoV-2 were evaluated regarding TFTs and divided into a severe (intubation, intensive care treatment) and an intermediate group. Results: Thyroidal ACE2 expression was detected in 87% of the deceased COVID-19 patients. Normal thyroid tissue from patients without SARS-CoV-2 infection showed no ACE2 protein expression. Half of the severely ill COVID-19 patients had low free triiodothyronine (fT3) levels. Combination of low fT3 and thyrotropin (TSH) was associated significantly with deadly disease. Conclusion: The high percentage of positive ACE2 immunostaining in deceased patients compared with normal thyroid tissue of patients without SARS-CoV-2 infection suggests involvement of the thyroid in COVID-19, although further research will have to show the pathogenic role of thyroidal ACE2 in COVID-19. Abnormal fT3 and a TSH of ≤0.5 mU/L were associated with a fatal outcome in our severely ill SARS-CoV-2 patient cohort. Therefore, assessment of TFTs is crucial in the treatment of severely ill COVID-19 patients. Trial Registration: COVID-19 Registry of the LMU University Hospital Munich (CORKUM), WHO trial ID DRKS00021225.