Transcriptomic analyses reveal three distinct molecular subgroups of Merkel cell carcinoma with differing prognoses.

Merkel cell carcinoma (MCC) is a cutaneous neuroendocrine malignancy with a poor prognosis and an unknown cell of origin. Proffered cells of origin include epithelial stem cells of the hair follicle or interfollicular epidermis, dermal stem cells and pro/pre- or pre-B cells. MCC has also been proposed to have more than one cell of origin and indeed to represent more than one type of carcinoma, currently grouped together due to phenotypic similarities. We explored the heterogeneous nature of MCC by studying the most variably expressed genes with the goal of identifying gene expression patterns that are either clinically relevant or have implications regarding the cell(s) of origin. We performed RNA sequencing on primary tumor samples from 102 patients and identified the top 200 most variably expressed genes. These genes and the tumor samples were hierarchically clustered based on their expression. The functions of three gene clusters exhibiting clearly divergent expression between samples were studied by cross-referencing the lists of genes with online databases. High expression of a gene cluster related to embryonic developmental processes and low expression of a gene cluster related to neuroendocrine processes distinguished Merkel cell polyomavirus (MCPyV)-negative tumors from MCPyV-positive tumors. Furthermore, two prognostically relevant subgroups of MCPyV-positive MCC were identified based on dichotomic expression of genes related to epidermal structures and processes. We identified three distinct molecular subgroups of MCC with prognostic relevance. We propose that the dichotomic expression of epidermis-related genes might reflect both an epidermal and a nonepidermal origin for MCPyV-positive MCC.

Radiation-associated angiosarcoma of the breast: analysis of diagnostic tools in a registry-based population.

BACKGROUND: Radiation-associated angiosarcoma of the breast (RAASB) is a serious late consequence caused by breast cancer treatment. Initial symptoms are often inconspicuous, thus contributing to diagnostic delay. Most previous studies of the diagnostic aspects of RAASB are case reports. PURPOSE: To perform a complete review of the imaging findings and biopsy methods in a nationwide RAASB cohort. MATERIAL AND METHODS: RAASB patients were identified from a national cancer registry and additional patients were included from our hospital. All available information from imaging (mammogram [MGR], ultrasound [US], magnetic resonance imaging [MRI], and computed tomography [CT]) and biopsies was reviewed. The sensitivity of imaging and biopsy methods for detection of RAASB was calculated. RESULTS: Fifty-eight patients with RAASB were found. Fourteen MGR, 30 US, 24 MRI, and 25 CT studies were available for evaluation. The sensitivity of MGR, US, MRI, and CT for detection of RAASB was 43%, 50%, 92%, and 84%, respectively. Superior sensitivity was demonstrated for punch biopsy (84%) and incisional biopsy (93%) compared to fine-needle aspiration cytology (0%) and core needle biopsy (18%). CONCLUSION: MRI and CT have comparable sensitivity for detection of RAASB, while MGR and US are unreliable. However, negative findings in MRI or CT must be interpreted with caution. Punch biopsy and incisional biopsy are the preferred biopsy methods.

Treatment and Prognosis of Radiation-Associated Breast Angiosarcoma in a Nationwide Population.

BACKGROUND: Radiation-associated angiosarcoma of the breast (RAASB) is an aggressive malignancy that is increasing in incidence. Only a few previous population-based studies have reported the results of RAASB treatment. METHODS: A search for RAASB patients was carried out in the Finnish Cancer Registry, and treatment data were collected to identify prognostic factors for survival. RESULTS: Overall, 50 RAASB patients were identified. The median follow-up time was 5.4 years (range 0.4-15.6), and the 5-year overall survival rate was 69%. Forty-seven (94%) patients were operated on with curative intent. Among these patients, the 5-year local recurrence-free survival, distant recurrence-free survival, and overall survival rates were 62%, 75%, and 74%, respectively. A larger planned surgical margin was associated with improved survival. CONCLUSIONS: We found that the majority of RAASB patients were eligible for radical surgical management in this population-based analysis. With radical surgery, the prognosis is relatively good.

Improved prognosis in soft-tissue sarcoma of extremity and trunk wall.

Background and purpose - Soft-tissue sarcoma (STS) is rare, with challenging individualized treatment, so diagnostics and treatment should be centralized. Historical controls are sometimes used for investigation of whether new diagnostic or therapeutic tools affect patient outcome. However, as yet unknown factors may affect the outcome. We investigated prognostic factors and prognosis in 2 nationwide cohorts of patients diagnosed with a local STS during the periods 1998-2001 and 2005-2010, with special interest in finding factors lying behind possible improvement of prognosis. Patients and methods - 2 cohorts of patients with STS of the extremities or trunk diagnosed during the periods 1998-2001 and 2005-2010 were retrieved from the nationwide Finnish Cancer Registry. Detailed information was gathered from patient files. Results - Compared to first cohort, a larger proportion of patients with inadequate surgery in the second cohort received radiation therapy, and both the local control rate and the sarcoma-specific survival rate improved in the second cohort. For sarcoma-specific survival, cohort (HR =0.6, 95% CI: 0.5-0.9), age, depth, grade, and margin were significant factors in multivariate analysis. For local control, cohort (HR =0.6, 95% CI: 0.5-0.9), age, and margin were significant in multivariate analysis. Interpretation - Known prognostic factors including type of treatment did not entirely explain the secular trend of continuous improvement in prognosis in STS. This illustrates the danger of using historical controls for investigation of whether new diagnostic or therapeutic tools have an effect on patient outcome.

Marginal miss or radioresistance? The pattern of local recurrence after operation and 3D planned radiation treatment in soft tissue sarcoma of the extremities and the limb girdles; an analysis based on image fusion.

BACKGROUND: Most local recurrences have developed in the clinical target volume in previously published series after combined modality treatment for soft tissue sarcoma. However, marginal misses were seen in almost 20% of the patients. The aim of the present study was to determine the location of the recurrence and the total dose at the centre point of the local recurrence for future radiation therapy planning. MATERIAL AND METHODS: We included only patients with images in digital form, during 1999-2006 (n = 17), treated for soft tissue sarcoma with combined surgical therapy and radiotherapy at Helsinki University Central Hospital. Image fusion was used to determine the location of the recurrence in relation to radiation therapy target. RESULTS: In the present study utilising digital image fusion, in patients with 3D CT-based radiation treatment planning the risk of marginal miss was low as only one patient of 17 relapsed outside the target. Estimated mean radiation dose at the site of local recurrence was 49.1 Gy in patients with positive margins and 48.1 Gy in patients with negative margins. CONCLUSION: The risk of marginal miss in soft tissue sarcoma is low after modern 3D planned radiation treatment combined with surgery. More generous use of boost might improve in-target local control.

Soft tissue sarcoma - a population-based, nationwide study with special emphasis on local control.

BACKGROUND: A prospective diagnostics and treatment protocol for extremity and trunk wall soft tissue sarcoma (STS) was introduced by the Scandinavian Sarcoma Group in 1986 and it was also widely adopted in Finland. We have updated the protocol and made it more detailed at the Helsinki University Central Hospital. We retrospectively compared diagnostics and treatment of STS in a nationwide population-based material to this protocol with special emphasis on local control. METHODS: Data for 219 patients with an STS of extremity or trunk wall diagnosed during 1998-2001 was retrieved from the nationwide Finnish Cancer Registry. Histologic review was performed. Treatment centres were divided into high-, intermediate- and low-volume centres based on the number of patients with final surgery during the study period. RESULTS: Significantly more patients were operated with a preoperative histological or cytological diagnosis at high-volume centres. No preoperative diagnosis was a strong predictor for the patient to undergo more than one operation (p < 0.0001). Wide surgical margin was achieved more often at high-volume centres, but in all centre categories a considerable percentage of patients with inadequate surgical margin did not receive adjuvant radiation therapy. Local control at five years was 82% at high-volume centres, 61% at intermediate-volume centres treating highest percentage of deep tumours and 69% at low-volume centres (p = 0.046). Local control improved as the number of patients operated (surgical volume of the centre) increased. CONCLUSION: The present quality-control study is the first nationwide population-based study to assess diagnostics and treatment of STS. When referred to a specialised sarcoma centre even patients with inadequate surgery can achieve good local control. STS is a rare cancer and its treatment should be centralised in Finland, which has 5.4 million inhabitants and approximately 100 new STSs of extremities and trunk wall annually.

Visual Counting and Automated Image-analytic Assessment of Ki-67 and their Prognostic Value in Synovial Sarcoma.

Background: Ki-67 is a widely used proliferation marker reflecting prognosis in various tumors. However, visual assessment and scoring of Ki-67 suffers from marked inter-observer and intra-observer variability. We aimed to assess the concordance of manual counting and automated image-analytic scoring methods for Ki-67 in synovial sarcoma. Patients and Methods: Tissue microarrays from 34 patients with synovial sarcoma were immunostained for Ki-67 and scored both visually and with 3DHistech QuantCenter. Results: The automated assessment of Ki-67 expression was in good agreement with the visually counted Ki-67 (r Pearson =0.96, p<0.001). In a Cox regression model automated [hazard ratio (HR)=1.047, p=0.024], but not visual (HR=1.063, p=0.053) assessment method associated high Ki-67 scores with worse overall survival. Conclusion: The automated Ki-67 assessment method appears to be comparable to the visual method in synovial sarcoma and had a significant association to overall survival.

Vascular invasion is an early event in pathogenesis of Merkel cell carcinoma.

This study investigated vascular and especially lymphovascular invasion in primary Merkel cell carcinoma and its value as a prognostic factor. Paraffin-embedded blocks prepared from tumor samples obtained from 126 patients diagnosed with Merkel cell carcinoma in 1979-2004 were immunohistochemically stained using antibodies CD31 and D2-40 to detect intravascular tumor emboli. This finding was compared with the clinical data and the disease outcome. Intravascular tumor cells were observed in 117 (93%) of the samples. The majority, 83 (66%), showed only lymphovascular invasion. Only blood vascular invasion was seen in four (3%) samples. In all, 30 (24%) samples demonstrated both lymphovascular invasion and blood vascular invasion. In only nine (7%) samples, there was no invasion within the vascular structures. The tumors lacking invasion were significantly smaller (P<0.01 and alpha=0.050) than those with vascular invasion, although lymphovascular invasion was observed even in the smallest tumor (0.3 cm) of this study. Already in the early stages of the disease, Merkel cell carcinoma seems to have the capacity to penetrate vessel walls. Our finding of the high frequency of lymphovascular invasion might therefore explain the extremely aggressive clinical behavior of Merkel cell carcinoma. This may support the role of sentinel node biopsy even in the case of very small primary Merkel cell carcinoma tumors.

Osteosarcoma in Finland from 1971 through 1990: a nationwide study of epidemiology and outcome.

BACKGROUND AND PURPOSE: There have only been a few nationwide studies on the epidemiology and outcome of osteosarcoma. We report the clinical features, treatment, and prognosis of osteosarcoma in Finland for the period 1971-1990. METHODS: The study material was derived from population-based data from the national Finnish Cancer Registry. 302 osteosarcomas were reported during the study period. Histological slides could be retrieved for 199 cases and from histological re-examination, 139 (83%) of these cases were confirmed as osteosarcoma and were included in the analysis. The mean length of follow-up was 8 (0.1-28) years. RESULTS: The overall 5-year survival for the whole study population was 58%, with an improvement in survival during 1981-1990 (65%) compared to the period 1971-1980 (47%) (p=0.01). More chemotherapy was administered in the later time period. For metastasis-free survival, diagnosis in the 1970s as opposed to the 1980s (p=0.01) and large tumor size worsened outcome in univariate analysis. Patients who developed metastatic relapse within 10 months of the diagnosis had worse sarcoma-specific survival than those who developed metastases later. Limb-salvage surgery increased from 12% to 23% for patients with a peripheral tumor, with no increase in local relapses. INTERPRETATION: We recommend aggressive approach to treat recurrent disease, with a view to further improving survival. In a small country such as Finland it is necessary to concentrate treatment to only a few centers, to ensure a high quality of treatment.

Radiation-associated sarcoma after breast cancer in a nationwide population: Increasing risk of angiosarcoma.

Radiation-associated sarcoma (RAS) is a rare complication of radiation therapy (RT) to breast cancer (BC). This study explored RAS after RT to BC in a nationwide population-based material. The Finnish Cancer Registry was queried for patients with BC treated during 1953-2014 who were later diagnosed with a secondary sarcoma in 1953-2014. Registry data, patient files, and sarcoma specimens were  analyzed to confirm diagnosis and location of RAS at or close to the RT target volume. A total of 132 512 patients were diagnosed with invasive BC during the study period. A subsequent sarcoma was diagnosed in 355 patients. After exclusion, 96 RAS were identified. Angiosarcoma (AS) was the most prevalent histology in 50 (52%) of 96 patients. However, the first radiation-associated AS was diagnosed in a patient treated for BC with breast-conserving surgery in 1984, and thereafter, the proportion of AS continuously increased. The 5-year sarcoma-specific survival was 75.1% for RAS treated with a curative intent. The distribution of histologic subtypes of RAS has changed during the 60 years of this registry study. The first radiation-associated AS was diagnosed in 1989, and presently, AS is the most common histologic subtype of RAS. It is possible that changes in BC treatment strategies are influencing the characteristics of RAS.

The desmoid tumour: local control after surgical treatment.

Desmoid tumours are uncommon non-malignant tumours that show a locally aggressive growth pattern and a high local recurrence rate after surgery. Approximately 10% of the desmoid tumours are associated with familial adenomatous polyposis (FAP). Variable natural history of the disease challenges treatment decision-making in the absence of prospective, randomised data. Association of this rare tumour to GIST is speculated and the tumorigenesis may share common steps. This study reviews given treatment and reports prognostic factors for local control and concurrent neoplasms in patients evaluated by a single soft tissue tumour group. Patients referred to the soft tissue tumour group at Helsinki University Central Hospital (HUCH) for a desmoid tumour (primary or recurred) during 1987-2007 and receiving surgical treatment with or without adjuvant treatment were included in this retrospective review. All locations and also patients with a FAP-associated tumour were included. Extra-abdominal location showed lower local control despite the fact that 27% of patients also received radiation therapy. One amputation was performed. Female sex and location in the rectus abdominis muscle predicted improved local control in multivariate analysis. In this review, the occurrence (14%) of concurrent neoplasms was higher than expected with unusual tumour types noted including two GISTs. In those patients in whom surgical treatment is chosen, adjuvant radiation therapy should also be considered in order to decrease morbidity from aggressive surgery aiming at R0 resection. Further studies are suggested to illuminate the biological association between the desmoid tumour and other neoplasms.

Chemoradiotherapy in the treatment of inoperable high-grade osteosarcoma.

Radical surgery is not feasible for all osteosarcoma patients. Overall survival for non-extremity osteosarcoma, as well as for patients with metastatic disease at diagnosis remains poor. For such patients, radical radiotherapy combined with chemotherapy may present an effective treatment approach. This report describes the results of conservative treatment for osteosarcoma patients not suitable for surgery. Seven out of 71 consecutive osteosarcoma patients were treated non-surgically at the Helsinki University Central Hospital either due to the inoperability of the tumour or the patient's choice of therapy. Staging procedures and measurement of tumour size were performed using computed tomography and magnetic resonance imaging. Six patients were treated with chemo-radiotherapy, and one patient received radiotherapy alone. Five patients received computer-assisted dose-planned radiotherapy with curative intent (total dose 60-70.5 Gray), and two patients received radiotherapy as palliation. Radiotherapy relieved symptoms efficiently. Median time to local failure was 2.6 years (range 0.5-16.9+ years). Five year after treatment termination four patients were alive, and one of them remained disease-free. For selected patients not suitable for surgery, radiotherapy combined with chemotherapy provides an option to reduce symptoms caused by the primary tumour and improve quality of life. For some patients, this approach may (even) produce long-term remission.

No improvement in the overall survival of 194 patients with chondrosarcoma in Finland in 1971-1990.

We describe the clinicopathologic profile and survival of 306 patients with chondrosarcoma reported to the Finnish Cancer Registry in 1971-1990. 218 cases were available for reevaluation. Owing to their various clinicopathologic characteristics, we excluded the histologic variants of chondrosarcoma. Therefore, the final study population included 194 patients. The minimum follow-up was 9 years. The study population included 69 grade 1 tumors, 114 grade 2 tumors, and 11 grade 3 tumors. The commonest tumor sites were the chest, pelvis and femur. A local recurrence developed in 25% of the patients and metastatic lesions in 18%. The patients were treated in 31 hospitals (in 22 hospitals during the 1970s and in 26 in the 1980s), and the number of patients biopsied before the referral remained about the same from the 1970s (15%) to the 1980s (18%). The 5-and 10-year disease-specific survival rates were 70% and 57%, respectively. Multivariate analysis showed that the most important independent predictors of shortened survival were high histologic grade, age 50 years or older, and a diagnosis in the 1980s, as compared to the 1970s. Most findings accorded with reports from specialist treatment centers, but to our surprise, the survival rate declined among patients diagnosed in the 1980s versus the 1970s. The failure to improve patient survival is probably due to treatment of the patients in 31 hospitals rather than in a few centers dealing with treatment of cancer.