Long-term outcome after surgical resection of non-high-risk gastrointestinal stromal tumours without adjuvant therapy.

BACKGROUND: Gastrointestinal stromal tumour (GIST) is the most common intra-abdominal sarcoma. Risk classification systems, commonly the modified National Institutes of Health consensus criteria, identify tumour properties relating to patient outcomes. However, owing to limited long-term evidence, most guidelines recommend up to 10-year follow-up for all risk groups except very low-risk GIST. METHODS: This retrospective multicentre study included patients who had complete resection of primary, non-metastatic GIST from three Scandinavian sarcoma centres: Gothenburg (2004-2020), Stockholm (2000-2019), and Oslo (2000-2017). Medical records were reviewed for clinical details regarding diagnosis, treatment, and follow-up, and recurrence-free and disease-specific survival evaluated. RESULTS: The total cohort consisted of 1213 patients with GIST. High-risk patients and those treated with tyrosine kinase inhibitors were excluded. The remaining 649 patients were included in the present analysis: 118 with very low-, 381 with low-, and 150 with intermediate-risk GISTs. Five-year recurrence-free survival rates were 100, 98.5, and 100 per cent for the intermediate-, low-, and very low-risk groups respectively (P = 0.246). Disease-specific survival rates 10 years after surgery were 100, 98.4, and 100 per cent for the intermediate-, low-, and very low-risk groups respectively (P = 0.262). CONCLUSION: Patients with completely resected non-high-risk GISTs have an excellent long-term outcome, irrespective of risk group. Follow-up programmes to detect disease recurrences in these patients are probably not indicated.

Gastrointestinal stromal tumours (GISTs) originate from the muscle layer of the gastrointestinal tract. They are divided into risk groups according to size, location, and how quickly they grow. Patients with GIST, regardless of risk group, have been followed with imaging for several years after their tumour has been successfully removed with an operation. The aim of this study was to evaluate whether follow-up is necessary for patients in the lower-risk groups. Six hundred and forty-nine patients with GISTs from the lower-risk groups were followed for 5 years (median). Only 1.2 per cent of the patients experienced a recurrence of their cancer. It was concluded that patients with GIST in the lower-risk groups do not need follow-up with imaging after a successful operation.

The spectrum and frequency of histopathological diagnosis of oral diseases in Oslo: Implications to oral pathology syllabus.

INTRODUCTION: To assure knowledge and skills in diagnostic work of oral diseases a continuously updated curriculum is essential. The first aim of the present study was to evaluate the spectrum and frequency of oral histopathological diagnoses signed out by oral pathologists at the Department of Pathology, Oslo University Hospital (OUS), Norway during a two-year period. The second aim was to compare the spectrum of histopathological diagnoses with the content of the current syllabus in oral pathology at the Faculty of Dentistry, University of Oslo (UiO). MATERIALS AND METHODS: In this retrospective cross-sectional study, all histological diagnosis signed out during 2015 and 2016 were included. All histopathological reports were analysed with regard to clinical information and histopathological diagnosis. The spectrum of histopathological diagnoses was compared to the diagnoses presented in lectures and courses for dental and dental hygienist students at UiO. RESULTS: Three thousand four hundred and two histopathological reports (47% males and 53% females) were included. The diagnoses were categorised into eight disease groups and the three most frequent disease groups were cysts, benign tumours/reactive lesions, and white, red, ulcerative and vesiculobullous lesions. The lateral periodontal cyst was more frequent than expected. CONCLUSIONS: We conclude that a minor revision of the syllabus is needed, although the most frequent oral conditions presented in this study are well covered in the oral pathology teaching in Oslo. A more clinical related teaching approach should be considered by categorising oral diseases according to, for example location and age groups.

Validation of a novel risk score to predict early and late recurrence in solitary fibrous tumour.

BACKGROUND: Current risk models in solitary fibrous tumour (SFT) were developed using cohorts with short follow-up and cannot reliably identify low-risk patients. We recently developed a novel risk model (G-score) to account for both early and late recurrences. Here, we aimed to validate the G-score in a large international cohort with long-term follow-up. METHODS: Data were collected from nine sarcoma referral centres worldwide. Recurrence-free interval (RFi) was the primary endpoint. RESULTS: The cohort comprised 318 patients with localised extrameningeal SFTs. Disease recurrence occurred in 96 patients (33%). The estimated 5-year RFi rate was 72%, and the 10-year RFi rate was 52%. G-score precisely predicted recurrence risk with estimated 10-year RFi rate of 84% in low risk, 54% in intermediate risk and 36% in high risk (p < 0.001; C-index 0.691). The mDemicco (p < 0.001; C-index 0.749) and SalasOS (p < 0.001; C-index 0.674) models also predicted RFi but identified low-risk patients less accurate with 10-year RFi rates of 72% and 70%, respectively. CONCLUSIONS: G-score is a highly significant predictor of early and late recurrence in SFT and is superior to other models to predict patients at low risk of relapse. A less intensive follow-up schedule could be considered for patients at low recurrence risk according to G-score.

Improving public cancer care by implementing precision medicine in Norway: IMPRESS-Norway.

BACKGROUND: Matching treatment based on tumour molecular characteristics has revolutionized the treatment of some cancers and has given hope to many patients. Although personalized cancer care is an old concept, renewed attention has arisen due to recent advancements in cancer diagnostics including access to high-throughput sequencing of tumour tissue. Targeted therapies interfering with cancer specific pathways have been developed and approved for subgroups of patients. These drugs might just as well be efficient in other diagnostic subgroups, not investigated in pharma-led clinical studies, but their potential use on new indications is never explored due to limited number of patients. METHODS: In this national, investigator-initiated, prospective, open-label, non-randomized combined basket- and umbrella-trial, patients are enrolled in multiple parallel cohorts. Each cohort is defined by the patient's tumour type, molecular profile of the tumour, and study drug. Treatment outcome in each cohort is monitored by using a Simon two-stage-like 'admissible' monitoring plan to identify evidence of clinical activity. All drugs available in IMPRESS-Norway have regulatory approval and are funded by pharmaceutical companies. Molecular diagnostics are funded by the public health care system. DISCUSSION: Precision oncology means to stratify treatment based on specific patient characteristics and the molecular profile of the tumor. Use of targeted drugs is currently restricted to specific biomarker-defined subgroups of patients according to their market authorization. However, other cancer patients might also benefit of treatment with these drugs if the same biomarker is present. The emerging technologies in molecular diagnostics are now being implemented in Norway and it is publicly reimbursed, thus more cancer patients will have a more comprehensive genomic profiling of their tumour. Patients with actionable genomic alterations in their tumour may have the possibility to try precision cancer drugs through IMPRESS-Norway, if standard treatment is no longer an option, and the drugs are available in the study. This might benefit some patients. In addition, it is a good example of a public-private collaboration to establish a national infrastructure for precision oncology. Trial registrations EudraCT: 2020-004414-35, registered 02/19/2021; ClinicalTrial.gov: NCT04817956, registered 03/26/2021.

Real-world evidence on perioperative chemotherapy in localized soft tissue sarcoma of the extremities and trunk wall; a population-based study.

BACKGROUND: Data from the real-world setting on perioperative chemotherapy in high-risk, localized soft tissue sarcoma (STS) is limited. Real-world data (RWD) includes data derived from patients treated outside clinical trials and often captures long-term follow-up not recorded in clinical trials. The aim of this study was to provide population-based, real-world evidence on perioperative chemotherapy in localized STS. MATERIAL AND METHODS: Adult patients with localized STS in the extremities or trunk wall treated at Oslo University Hospital, Oslo, Norway from 1998 to 2017 were included in the study. Data were extracted from a prospectively maintained database, supplemented by retrospective review of medical records. RESULTS: The total study cohort included 806 patients, of whom 154 (19%) received perioperative chemotherapy. A regimen with anthracycline and ifosfamide was given in 141 of 154 cases (92%). During long-term follow-up two patients developed secondary malignancies, cardiac toxicity was registered in 11 patients (7%) and renal toxicity in 12 patients (8%). Seventy-one of 154 patients (46%) were treated outside of clinical trials and constituted the RWD cohort. The median age at surgery was slightly lower and there were more synovial sarcomas and fewer myxofibrosarcomas in the RWD cohort. No difference in chemotherapy dose intensity was observed. The estimated 5-year metastasis-free survival (MFS) in all patients receiving perioperative chemotherapy was 58%. In the RWD cohort 5-year MFS was 53% and in the clinical study cohort 61% (HR 1.24; 95% CI 0.77-2.00). CONCLUSION: Long-term outcome after perioperative chemotherapy was comparable for patients treated in routine clinical practice to those in clinical trials. Secondary malignancy and cardiac toxicity were observed. The risk of serious late side effects should be included in the decision process on perioperative chemotherapy.

A novel risk score to predict early and late recurrence in solitary fibrous tumour.

AIMS: Solitary fibrous tumours (SFTs) are rare mesenchymal neoplasms with recurrence rates of 10-30%. Current risk stratification systems for extrameningeal SFTs are based on cohorts with limited follow-up and are not suitable for prediction of late recurrences. In this study we aimed to develop a prognostic model accounting for both early and late recurrences using a relatively large patient cohort with long-term follow-up. METHODS AND RESULTS: Clinicopathological factors were analysed in a cohort of 100 extrameningeal, STAT6-positive SFTs. Median follow-up for overall survival (OS) and recurrence-free interval (RFi) were 121 and 84 months, respectively. Disease relapse occurred in 31% of patients and median time to recurrence was 63 months. In univariate analysis mitotic count, necrosis, male gender and presence of severe atypia and pleomorphism were associated with inferior RFi. Mitotic count, necrosis and male gender were independent predictors of recurrence in multivariate analysis. Previously published risk models were also statistically associated with RFi in our cohort, but failed to reliably identify low-risk patients due to poor prediction of late recurrences. A novel risk score based on mitotic count, necrosis and gender was able to stratify patients into low-, intermediate- and high-risk groups for both early and late recurrences. CONCLUSIONS: In this cohort of patients with extrameningeal SFT and long-term follow-up mitotic count, necrosis and gender were independent prognostic markers of recurrence. We propose a novel risk score based on these factors and accounting for late recurrences, which should be validated in external cohorts with sufficient follow-up time.

Risk stratification for central conventional chondrosarcoma of bone: A novel system predicting risk of metastasis and death in the Cancer Registry of Norway cohort.

BACKGROUND AND OBJECTIVES: Interobserver variability in histological grading of central conventional chondrosarcoma (CCCS) limits the quality of patient information and research progression. We aim to quantify known and new prognostic variables and propose a risk stratification model. METHOD: We selected 149 cases from the Cancer Registry of Norway. Cox proportional hazard models were estimated. Based on these results a dichotomous risk classification was proposed and presented by Kaplan-Meier estimates for rates of local recurrence, metastasis, and disease-specific survival. RESULTS: The influence of axial skeletal location (Hazard ratio [HR] = 19.06), a soft tissue component ≥1 cm (HR = 13.45), and histological grade 3 (HR = 16.46) are all significant in predicting the rate of metastasis. The creation of a variable combining axial skeletal location and a soft tissue component ≥1 cm strongly predicts the risk of metastasis (HR = 14.02; P < .001) and death (HR = 2.74; P = .030) at multivariate analysis, making the histological grade insignificant. Together with metastasis at diagnosis (HR = 285.65; P < .001), this forms the basis of our proposed risk stratification, producing a small high-risk group (39 cases with 33% risk of metastasis) and a large low-risk group (103 cases with 2% risk of metastasis) without a histological grade. CONCLUSION: Axial skeletal location and a soft tissue component ≥1 cm combined divides a CCCS cohort into low- and high-risk groups without a histological grade.

Chondrosarcoma in Norway 1990-2013; an epidemiological and prognostic observational study of a complete national cohort.

BACKGROUND: Knowledge of chondrosarcoma (CS) of bone to date is based on institutional reports and registry publications with limits in reporting, detail and quality of data. METHOD: We have performed a retrospective search of CS of bone in the National Cancer Registry in Norway from 1990-2013, cross checked against local tumor databases with further quality control and supplementation of all data from clinical files. The time period is defined by the routine use of axial imaging in clinical practice. A total of 311 cases are included. We performed 108 pathological reviews and 223 radiological reviews. The manuscript was prepared according to the STROBE checklist for strengthening of observational studies. We performed uni-/multivariate cox analyses to define independent prognostic variables from the main cohort of central CS of bone. RESULTS: The incidence of CS of bone in Norway is 2.85/million/yr. for both sexes overall, rising to 3.45/million/yr. in the last 5-year period. There is an increase in the most common central CS subtype, stronger for women than for men. Central CS had, in general 10-15% local recurrence rates, all evident by 5 years while metastasis rate increases with location and grade. Exceptions are extremity grade 1 CS which displayed no metastatic events and axial grade-3 disease with high rates (50%) of both local and metastatic relapse. Peripheral CS had limited metastatic potential (2%), but rates of local relapse (13%) continue to appear towards 10 years of follow up. Malignancy grade 3 independently predicts rate of metastasis and presence of soft tissue component predicts local recurrence, metastasis and survival. CONCLUSION: Rates of local recurrence, metastasis and disease specific survival follow clear patterns depending on subtype, location and grade allowing better tailoring of follow-up regimes. Malignancy grade 3 and the presence of a soft tissue component independently predict behavior for central CS of bone.

Inferior survival for patients with malignant peripheral nerve sheath tumors defined by aberrant TP53.

Malignant peripheral nerve sheath tumor is a rare and aggressive disease with poor treatment response, mainly affecting adolescents and young adults. Few molecular biomarkers are used in the management of this cancer type, and although TP53 is one of few recurrently mutated genes in malignant peripheral nerve sheath tumor, the mutation prevalence and the corresponding clinical value of the TP53 network remains unsettled. We present a multi-level molecular study focused on aberrations in the TP53 network in relation to patient outcome in a series of malignant peripheral nerve sheath tumors from 100 patients and 38 neurofibromas, including TP53 sequencing, high-resolution copy number analyses of TP53 and MDM2, and gene expression profiling. Point mutations in TP53 were accompanied by loss of heterozygosity, resulting in complete loss of protein function in 8.2% of the malignant peripheral nerve sheath tumors. Another 5.5% had MDM2 amplification. TP53 mutation and MDM2 amplification were mutually exclusive and patients with either type of aberration in their tumor had a worse prognosis, compared to those without (hazard ratio for 5-year disease-specific survival 3.5, 95% confidence interval 1.78-6.98). Both aberrations had similar consequences on the gene expression level, as analyzed by a TP53-associated gene signature, a property also shared with the copy number aberrations and/or loss of heterozygosity at the TP53 locus, suggesting a common "TP53-mutated phenotype" in as many as 60% of the tumors. This was a poor prognostic phenotype (hazard ratio = 4.1, confidence interval:1.7-9.8), thus revealing a TP53-non-aberrant patient subgroup with a favorable outcome. The frequency of the "TP53-mutated phenotype" warrants explorative studies of stratified treatment strategies in malignant peripheral nerve sheath tumor.

Recurrence-Free Survival After Resection of Gastric Gastrointestinal Stromal Tumors Classified According to a Strict Definition of Tumor Rupture: A Population-Based Study.

BACKGROUND: In gastrointestinal stromal tumors (GISTs), rupture is a high-risk feature and an indication for adjuvant treatment; however, the independent impact of rupture on prognosis is uncertain and the term is inconsistently defined. In the present study, a previously proposed definition of 'tumor rupture' was applied on a population-based cohort of gastric GISTs. METHODS: Patients undergoing surgery for non-metastatic gastric GISTs from 2000 to 2015 were identified in the regional sarcoma database of Oslo University Hospital. Tumor rupture included spillage or fracture, piecemeal resection, incisional biopsy, blood-tinged ascites, gastric perforation, and microscopic adjacent infiltration. Minor defects of tumor integrity were not considered rupture, i.e. core needle biopsy, peritoneal tumor penetration, superficial peritoneal rupture, and R1 resection. Risk was assessed according to the modified National Institutes of Health consensus criteria. RESULTS: Among 242 patients, tumor rupture occurred in 22 patients and minor defects of tumor integrity occurred in 81 patients. Five-year recurrence-free survival (RFS) for patients with tumor rupture, minor defects of tumor integrity, and no defect was 37, 91, and 96%, respectively (p < 0.001). In the high-risk group, 5 year RFS for patients with rupture was 37%, versus 77% without rupture (hazard ratio 3.56, 95% confidence interval 1.57-8.08, p = 0.001). On multivariable analysis, tumor rupture and mitotic index were independently associated with recurrence. Of 13 patients who received adjuvant imatinib after tumor rupture, 11 relapsed. CONCLUSIONS: Tumor rupture according to the present definition was independently associated with recurrence. With tumor rupture, patients relapsed despite adjuvant treatment. Without rupture, prognosis was good, even in the high-risk group.

Multimodal kreftbehandling av gastrointestinal stromal tumor.

Gastrointestinal stromal tumour (GIST) is a subtype of sarcoma that may occur in any part of the gastrointestinal system, most frequently in the stomach and small intestine. The most common symptoms are bleeding and abdominal pain. In this clinical review, we summarise the progress made with this condition and discuss the recommended diagnostics and treatment of GIST.

Use of liquid biopsies to monitor disease progression in a sarcoma patient: a case report.

BACKGROUND: Many patients experience local recurrence or metastases after receiving potentially curative treatment, and early detection of these events is important for disease control. Recent technological advances make it possible to use blood plasma containing circulating cell-free tumour DNA (ctDNA) as a liquid biopsy. In this case report we show how serial liquid biopsies can be used to monitor the disease course and detect disease recurrence in a sarcoma patient. CASE PRESENTATION: A 55-year-old male presented with a rapidly growing, painful palpable mass in the left groin region, and a biopsy revealed a high-grade malignant spindle cell sarcoma. No metastases were detected on radiologic imaging scans. Using targeted resequencing with a custom 900 cancer gene panel, eight somatic mutations among them KRAS and NF1, were identified in the primary tumour. Targeted resequencing of plasma cell-free DNA (ctDNA) collected before and after surgery and at disease progression confirmed the presence of six of eight mutations at all three time points. The ctDNA level, estimated from the somatic allele frequencies of these six mutations, was high in plasma taken at the time of surgery, at levels similar to the primary tumour. Detection of low levels of ctDNA three days after surgery indicated persistent microscopic disease. Repeated radiologic imaging six weeks postoperatively showed widespread metastatic disease in the lungs, skeleton and the pelvic region. At this time point there was a dramatic increase in the ctDNA level, reflecting the disease progression of the patient. The patient had an unusually aggressive cancer, and succumbed to the disease 13 weeks after surgery. CONCLUSIONS: This case report demonstrated that targeted resequencing of ctDNA from longitudinal collected plasma can be used to monitor disease progression in a soft tissue sarcoma patient, including manifestation of metastatic disease. The ctDNA represented the genomic profile of the tumour, supporting clinical use of liquid biopsies to identify tumour-specific mutations as well as recurrent disease.

Multimodal treatment of craniofacial osteosarcoma with high-grade histology. A single-center experience over 35 years.

High-grade craniofacial osteosarcoma (CFOS) is an aggressive malignancy with a poor prognosis. Our goals were to evaluate treatment outcomes in those treated at a single referral institution over 35 years and to compare our results to the available literature. A retrospective analysis of all 42 patients treated between 1980 and 2015 at Oslo University Hospital, Norway, identified in a prospectively collected database, was conducted. Mean follow-up was 79.6 months. Overall survival at 2 and 5 years was 70.5 and 44.7%, respectively. The corresponding disease-specific survival rates were 73.0 and 49.8%. Treatment was surgery only in eight cases. Additional therapy was administered in 34 patients: chemotherapy in nine, radiotherapy in seven, and a combination of these in 18 cases. Stratified analysis by resection margins demonstrated significantly better survival at 2 and 5 years after radical surgical treatment. Neoadjuvant chemotherapy and subsequent adequate surgery resulted in better survival than surgery alone. Half of the patients either had a primary or familial cancer predisposition. This is the largest single-center study conducted on high-grade CFOS to date. Our experience indicates that neoadjuvant chemotherapy with complete surgical resection significantly improved survival, compared to surgery alone.

The Scandinavian Sarcoma Group Central Register: 6,000 patients after 25 years of monitoring of referral and treatment of extremity and trunk wall soft-tissue sarcoma.

Purpose - We wanted to examine the potential of the Scandinavian Sarcoma Group (SSG) Central Register, and evaluate referral and treatment practice for soft-tissue sarcomas in the extremities and trunk wall (STS) in the Nordic countries. Background - Based on incidence rates from the literature, 8,150 (7,000-9,300) cases of STS of the extremity and trunk wall should have been diagnosed in Norway, Finland, Iceland, and Sweden from 1987 through 2011. The SSG Register has 6,027 cases registered from this period, with 5,837 having complete registration of key variables. 10 centers have been reporting to the Register. The 5 centers that consistently report treat approximately 90% of the cases in their respective regions. The remaining centers have reported all the patients who were treated during certain time periods, but not for the entire 25-year period. Results - 59% of patients were referred to a sarcoma center untouched, i.e. before any attempt at open biopsy. There was an improvement from 52% during the first 5 years to 70% during the last 5 years. 50% had wide or better margins at surgery. Wide margins are now achieved less often than 20 years ago, in parallel with an increase in the use of radiotherapy. For the centers that consistently report, 97% of surviving patients are followed for more than 4 years. Metastasis-free survival (MFS) increased from 67% to 73% during the 25-year period. Interpretation - The Register is considered to be representative of extremity and trunk wall sarcoma disease in the population of Scandinavia, treated at the reporting centers. There were no clinically significant differences in treatment results at these centers.

Recurrent fusion of the genes FN1 and ALK in gastrointestinal leiomyomas.

Leiomyomas of the gastrointestinal tract are mostly found in the esophagus, stomach, and colon. Genetic information about them is very limited and no fusion genes have been described. We present herein cytogenetic and molecular genetic analyses of two gastrointestinal leiomyomas found in the esophagus and small intestine. The esophageal leiomyoma had the karyotype 45,Y,der(X)t(X;6)(p22;p21),inv(2)(p23q35),add(6)(p21),-11[cp6]/46,XY[7]. The intestinal leiomyoma karyotype was 46,X,add(X)(q2?),der(2)add(2)(p23)add(2)(q33),add(4)(p14),add(14)(q22)[10]/47,XX,+12[2]/46,XX[1]. RNA-sequencing detected FN1-ALK fusion transcripts in both tumors. RT-PCR together with Sanger sequencing verified the presence of the FN1-ALK fusion transcripts. Fluorescence in situ hybridization using an ALK breakapart probe further confirmed the rearrangement of the ALK gene. Immunohistochemical investigation of ALK in the leiomyoma of the small intestine revealed positivity with strong granular cytoplasmatic staining in the tumor cells. This is the first ever ALK fusion reported in gastrointestinal leiomyomas. Our results are of potential clinical importance because crizotinib, a selective ALK inhibitor, has demonstrated effect in patients whose tumors harbor ALK rearrangements. Thus, ALK emerges as a possible therapeutic target in patients whose tumors, including gastrointestinal leiomyomas, carry ALK fusions.

Referral patterns, treatment and outcome of high-grade malignant bone sarcoma in Scandinavia--SSG Central Register 25 years' experience.

AIMS: The objectives of this study were to present changes in referral patterns, treatment and survival in patients with high-grade malignant bone sarcoma in Sweden and Norway based on data in the Scandinavian Sarcoma Group (SSG) Central Register. METHOD: Data on 1,437 patients with diagnosis 1986-2010 was analyzed. RESULTS: Osteosarcoma was the most frequentl diagnosis (45%), followed by Ewing sarcoma (21%) and chondrosarcoma (17%). Thirty-one percent of Swedish and 41% of Norwegian patients had tumors in the axial skeleton. Eighty-six percent of extremity tumors and 66% of axial tumors were referred to a sarcoma center prior to unplanned surgery or biopsy. During the past decade, limb salvage surgery has risen from under 50% to over 80%. Five-year overall survival in non-metastatic osteosarcoma was 70% for extremity tumors, and 35% for axial tumors. No improvement in osteosarcoma survival was observed during the last decade. Five-year survival in Ewing sarcoma improved from 50% to 69%. CONCLUSION: Referral patterns in bone sarcomas have improved. However, greater efforts should be dedicated to improving referral of patients with possible tumors in the axial skeleton to multidisciplinary teams (MDTs). Overall survival of patients with high-grade malignant bone sarcomas in Sweden and Norway is in line with other reports.

Time-trends on incidence and survival in a nationwide and unselected cohort of patients with skeletal osteosarcoma.

BACKGROUND: This study describes time-trends on epidemiology, subtypes and histopathological entities of osteosarcoma (OS) in a nationwide and unselected cohort of OS patients in Norway between 1975 and 2009. Few nationwide studies are published, and we still have particularly limited knowledge regarding patients not included in clinical trials comprising about half of the OS population. METHOD: Histologically verified skeletal OS for all subgroups were included, resulting in 473 eligible cases from a total of 702 evaluated patients. To ensure completeness, the present cohort was based on all cases reported to the Norwegian Cancer Registry, complemented with data from all Norwegian hospitals involved in sarcoma management. Survival analyses were performed with overall and sarcoma-specific survival as endpoints. RESULTS: Mean annual age-standard incidence amounted to about 3.8 per million in male and 2.8 per million in female with no clear time-trends. The male to female ratio was 1.4. Peak incidence was observed in the second decade for both genders. Conventional OS comprised 71.2% of all cases, while low grade OS represented 10.4% and telangiectatic OS only 1.3%. The most common primary site of OS was femur and tibia, respectively. The axial to appendicular ratio increased with the age. The overall 10-year survival did increase from about 30% during the late 1970s to around 50% 20 years later, with no subsequent improvement during the last two decades. Axial tumours, age above 40 years and overt metastatic disease at time of diagnosis were all negative prognostic factors. CONCLUSION: No improvement in the overall survival for OS since the 1990s was documented. The survival rates are still poor for elderly people, patients with axial disease and in the primary metastatic setting. The average incidence rate of skeletal OS in Norway was in line with international figures.

Response to preoperative chemotherapy in patients undergoing resection of pulmonary metastasis from soft tissue sarcoma - a predictor of outcome?

UNLABELLED: Approximately 50% of patients with high-grade soft tissue sarcoma (STS) will develop pulmonary metastasis. This is the most frequent cause of death and improving treatment is warranted. Preoperative chemotherapy is used for selected patients, usually those with less favorable prognosis and mainly outside clinical trials. The predicted value of histological and radiological response to preoperative chemotherapy on outcome was the main focus for this investigation. PATIENTS AND METHODS: This retrospective study comprises 93 patients with metachronous lung metastasis from STS who underwent complete metastasectomy alone (n = 41) or metastasectomy following preoperative chemotherapy (n = 52). Clinical data, histological and radiological responses to chemotherapy were recorded and survival analyses performed. RESULTS: The time from initial STS diagnosis to the appearance of metastasis was shorter in the preoperative chemotherapy group than in those treated with surgery alone (p = 0.02). However, no statistical differences in post-metastasis disease-specific survival (DSS) or progression-free survival (PFS) between the groups were demonstrated. Patients in the preoperative chemotherapy group with good (complete) histological response had improved PFS compared with poor responders (p = 0.04). Radiological partial response was an independent, favorable prognostic factor for improved PFS and DSS (p = 0.003). CONCLUSION: Despite having unfavorable disease characteristics, some patients may benefit from preoperative chemotherapy. Both histological and radiological responses to preoperative chemotherapy seem to be prognostic in STS patients undergoing complete pulmonary metastasectomy.

Fusion of the ZC3H7B and BCOR genes in endometrial stromal sarcomas carrying an X;22-translocation.

Endometrial stromal sarcomas (ESS) are genetically heterogeneous uterine tumors in which a JAZF1-SUZ12 chimeric gene resulting from the chromosomal translocation t(7;17)(p15;q21) as well as PHF1 rearrangements (in chromosomal band 6p21) with formation of JAZF1-PHF1, EPC1-PHF1, and MEAF6-PHF1 chimeras have been described. Here, we investigated two ESS characterized cytogenetically by the presence of a der(22)t(X;22)(p11;q13). Whole transcriptome sequencing one of the tumors identified a ZC3H7-BCOR chimeric transcript. Reverse transciptase-PCR with the ZC3H7B forward and BCOR reverse primer combinations confirmed the presence of a ZC3H7-BCOR chimeric transcript in both ESS carrying a der(22)t(X;22) but not in a control ESS with t(1;6) and the MEAF6-PHF1 fusion. Sequencing of the amplified cDNA fragments showed that in both cases ESS exon 10 of ZC3H7B (from 22q13; accession number NM_017590 version 4) was fused to exon 8 of BCOR (from Xp11; accession number NM_001123385 version 1). Reciprocal multiple BCOR-ZC3H7B cDNA fragments were amplified in only one case suggesting that ZC3H7B-BCOR, on the der(22)t(X;22), is the pathogenetically important fusion gene. The putative ZC3H7B-BCOR protein would contain the tetratricopeptide repeats and LD motif from ZC3H7B and the AF9 binding site (1093-1233aa), the 3 ankyrin repeats (1410-1509 aa), and the NSPC1 binding site of BCOR. Although the presence of these motifs suggests various functions of the chimeric protein, it is possible that its most important role may be in epigenetic regulation. Whether or not the (patho)genetic subsets JAZF1-SUZ12, PHF1 rearrangements, and ZC3H7B-BCOR correspond to any phenotypic, let alone clinically important, differences in ESS remain unknown.