The promise and challenges of rare cancer research

Molecular Tumor Board for Unicorns: Outcomes for rare and ultra-rare cancers using an N-of-One personalized treatment strategy

Treatment of rare/ultra-rare tumors is an unmet need due to a lack of standardized therapies and clinical trials. We developed the Molecular Tumor Board (MTB), a multidisciplinary team that integrates molecular profiling to generate personalized, N-of-One treatments for advanced cancers. This study evaluates 112 patients with rare/ultra-rare tumors who presented to the MTB and were evaluable for clinical therapeutic outcome. Overall, 46/112 patients (41%) received a treatment regimen with a high degree of matching between tumor molecular alterations and drugs given (reflected by a high Matching Score (≥50%)). Patients with a high versus low Matching Score experienced significantly longer progression-free survival (p = 0.005) and overall survival (p = 0.047), and higher rates of clinical benefit (stable disease ≥6 months, partial response, or complete response) (54% vs. 32% p = 0.027). The MTB facilitated personalized N-of-One matching of drugs to tumor molecular alterations, which was associated with improved clinical outcomes in patients with rare/ultra-rare cancers.

Unraveling molecular signatures in rare bone tumors and navigating the cancer pathway landscapes for targeted therapeutics

Rare cancers (RCs), which account for over 20% of cancer cases, face significant research and treatment challenges due to their limited prevalence. This results in suboptimal outcomes compared to more common malignancies. Rare bone tumors (RBTs) constitute 5-10% of rare cancer cases and pose unique diagnostic complexities. The therapeutic potential of anti-cancer drugs for RBTs remains largely unexplored. Identifying molecular alterations in cancer-related genes and their associated pathways is essential for precision medicine in RBTs. Small molecule inhibitors and monoclonal antibodies targeting specific RBT-associated proteins show promise. Ongoing clinical trials aim to define RBT biomarkers, subtypes, and optimal treatment contexts, including combination therapies and immunotherapeutic agents. This review addresses the challenges in diagnosing, treating, and studying RBTs, shedding light on the current state of RBT biomarkers, potential therapeutic targets, and promising inhibitors. Rare cancers demand attention and innovative solutions to improve clinical outcomes.

The efficacy of immunotherapy and chemoimmunotherapy in patients with advanced rare tumors: A Turkish oncology group (TOG) study

INTRODUCTION

The advances in immune checkpoint inhibitors (ICIs) were relatively slow in rare tumors. Therefore, we conducted a multi-center study evaluating the efficacy of ICI monotherapy and the combination of ICIs with chemotherapy (CT) in patients with advanced rare tumors.

METHODS

In this retrospective cohort study, we included 93 patients treated with ICIs for NCI-defined rare tumors from the 12 cancer centers in Turkey. The primary endpoints were the overall response (ORR) and disease control rate (DCR).

RESULTS

The cohort's median age was 56, and 53.8% of the patients were male. The most frequent diagnosis was sarcoma (29%), and 81.7% of the patients were previously treated with at least one line of systemic therapy in the advanced stage. The ORR and DCR were 36.8% and 63.2%, respectively. The germ cell tumors had the lowest ORR (0%), while the Merkel cell carcinoma had the highest ORR to ICIs (57.1%). Patients treated with ICI + ICI or ICI plus chemotherapy combinations had higher ORR (55.2% vs. 27.6%, p = 0.012) and DCR (82.8% vs. 53.4%, p = 0.008). The median OS was 13.47 (95% CI: 7.79-19.15) months, and the six and 12-month survival rates were 71% and 52%. The median duration of response was 16.59 months, and the 12-month progression-free survival rate was 66% in responders. The median time-to-treatment failure was 5.06 months (95% CI: 3.42-6.71). Three patients had high-grade irAEs with ICIs (grade 3 colitis, grade 3 gastritis, and grade 3 encephalitis in one patient each).

CONCLUSION

We observed over 30% ORR and a 13-month median OS in patients with rare cancers treated with ICI monotherapy or ICI plus CT combinations. The response rates to ICIs or ICIs plus CT significantly varied across different tumor types. Responding patients had over 2 years of survival, highlighting a need for further trials with ICIs for patients with rare tumors.

Long term outcome of complex surgical resection and reconstruction for rare thoracic cancers

BACKGROUND

Complex surgical resection and reconstruction for rare thoracic cancers (RTCs) represent a major challenge, given their very low frequency, extreme variability of presentation, multi-modality treatment options and inadequate outcome prediction. We analysed the experience of a tertiary referral centre on a consecutive series of patients with thoracic germ cell tumours, thymomas and sarcomas, with the aim of reporting the long-term outcome by cancer type and complexity of surgical procedures.

METHODS

From Jan 2003 to Dec 2018, 768 surgical procedures were performed with curative intent on 644 RTC patients. Study endpoints were: post-operative hospital stay (Pod), 30-day and 90-day mortality, 5-year and 10-year overall survival (OS). Median follow-up of alive patients was 7.2 years.

RESULTS

Median Pod was 7 days, with a 1.2% 30-day and 2.9% 90-day mortality. OS was 90.8% at one year, 74.2% at five years and 62.8% at 10 years. Ten-year OS was 73.0% in low, 65.3% in intermediate, and 55.6% in high complexity score (Log-rank tests p<0.0001); 66.6% in patients with one or two reconstructions and 46.4% in patients with three or more reconstructions (p<0.0001); 46.0% with vascular and 50.0% with chest wall reconstruction; 71.8% in germ cell tumours, 64.6% in thymoma and 51.3% in sarcoma (p<0.0001).

CONCLUSION

Complex surgical resection and reconstruction was associated with acceptable 90-day mortality and good 10-year survival in all RTC types. A predictive score based on surgical complexity and cancer type can help the clinical decision making.

Characteristics of Cancer Epidemiology Studies That Employ Metabolomics: A Scoping Review

An increasing number of cancer epidemiology studies use metabolomics assays. This scoping review characterizes trends in the literature in terms of study design, population characteristics, and metabolomics approaches and identifies opportunities for future growth and improvement. We searched PubMed/MEDLINE, Embase, Scopus, and Web of Science: Core Collection databases and included research articles that used metabolomics to primarily study cancer, contained a minimum of 100 cases in each main analysis stratum, used an epidemiologic study design, and were published in English from 1998 to June 2021. A total of 2,048 articles were screened, of which 314 full texts were further assessed resulting in 77 included articles. The most well-studied cancers were colorectal (19.5%), prostate (19.5%), and breast (19.5%). Most studies used a nested case-control design to estimate associations between individual metabolites and cancer risk and a liquid chromatography-tandem mass spectrometry untargeted or semi-targeted approach to measure metabolites in blood. Studies were geographically diverse, including countries in Asia, Europe, and North America; 27.3% of studies reported on participant race, the majority reporting White participants. Most studies (70.2%) included fewer than 300 cancer cases in their main analysis. This scoping review identified key areas for improvement, including needs for standardized race and ethnicity reporting, more diverse study populations, and larger studies.

Current picture of anaplastic thyroid cancer patients' care and meetable needs: A survey of 94 Institutions from the EORTC Endocrine and Head and Neck Cancer Groups

Anaplastic thyroid carcinoma (ATC) is a rare cancer accounting for 40% of thyroid cancer-specific deaths. In the last 5 years, improved insights into molecular pathways led the Food and Drug Administration to license BRAF/MEK inhibitors (B/Mi) in BRAF^V600E-mutant ATC, and pembrolizumab in solid cancer with high tumour mutational burden (TMB-H) (≥10 mutations/megabase) (mut/Mb). In Europe, clinicians face challenges in prescribing novel treatments, as the European Medical Association (EMA) has not licensed B/Mi nor immunotherapy (IO) for ATC so far. Some patients manage to receive these drugs through alternative ways. We investigated the extent of this phenomenon launching an online survey from March 12th to 19th 2021 open to 239 Institutions in the EORTC Endocrine and Head & Neck Cancer Groups. Questions enquired about the number of ATC patients evaluated/year, feasibility of BRAF assessment, accessibility to B/Mi-IO, availability of clinical trials and interest in new studies. Colleagues from 94 Institutions (20 Countries) joined: 30 centres evaluated ≥5 ATC patients/year, with an overall incidence >200 patients/year. 80.8% tested BRAF status, 43.6% by next-generation sequencing. 62.7% and 70% of responders reported limitations in prescribing B/Mi and IO, respectively: either the impossibility of offering them, or drugs accessibility exclusively under certain conditions (e.g. health insurance, clinical trials, compassionate use, off-label). Only 13.8% had clinical trials ongoing while 91.5% of sites claimed ATC-dedicated trials. Disparities in access to novel treatments are diffuse. Access to cutting-edge therapies is an urgent issue in this setting, and clinical trials seem feasible within an appropriate network.

Clinicopathological Patterns of Malignant Solid Tumors in Adult Patients: A Hospital-Based Study From Bangladesh

BACKGROUND

Solid malignant tumors are abnormal masses of tissue that usually do not contain any cysts or liquid areas. The causation of these tumors is multifactorial, and the disease process differs at different sites.

AIM

This study aims to determine the clinicopathological patterns of malignant solid tumors in adult patients admitted into the department of internal medicine of a tertiary care hospital in Bangladesh.

METHOD

This cross-sectional study was conducted between January 2018 and June 2018 at the Department of Medicine, Dhaka Medical College Hospital, Bangladesh. We recorded the complete socio-demographic characteristics, clinical patterns, and pathological characteristics of malignant solid tumors in adult patients.

RESULTS

A total of 100 patients with confirmed malignant solid tumors were included in our study. The mean age of the patients was 47.5 years (SD: ±4.20); most of them (27%) were between 58 and 67 years of age. Male patients constitute 59% of the total study sample. Most of the patients were of the middle socio-economic class (59%) and most of them (61%) were nonsmokers. Among the patient diagnoses, 19% had lung cancer, 29.27% had breast cancer, and in 14%, lymphoma (tumor arising from the lymphatic system) was the common solid tumor. Lung cancer was found to be the most common form of cancer in males. Additionally, the majority of those diagnosed with lung cancer smoked. Breast cancer was found to be the most common type of cancer in females.

CONCLUSION

This study reflects that solid malignant tumors can affect any socio-economic class of people. Based on findings in our study as well as others, prevention efforts should focus on the reduction in tobacco use and the incorporation of other lifestyle changes, such as diet modification and exercise. Additionally, the incorporation of economic factors and how they affect cancer presentation in different contexts is crucial.

Challenges and controversies patients and (health care) professionals experience in managing vaginal, vulvar, penile or anal cancer: The SILENCE study

OBJECTIVE

Patients with vaginal, vulvar, penile or anal cancer experience deteriorated psychosocial functioning and decreased Quality of Life (QoL). The aims of this study were to explore (1) the challenges and controversies patients experience in managing vaginal, vulvar, penile or anal cancer; their unmet needs; and how this affects their psychosocial functioning and (2) the gaps health care professionals (HCPs) experience in providing psychosocial support and potential improvements in care.

METHODS

Semi-structured interviews with patients with vaginal, vulvar, penile or anal cancer and with HCPs were conducted. All interviews were transcribed verbatim and thematically analysed.

RESULTS

Fourteen patients (86% female; mean age 55.5) and 12 HCPs (75% female; mean age 46.4) participated. Four themes were identified: (1) recognisable symptoms but unfamiliar diagnosis, (2) 'double hit' has severe impact on psychosocial functioning, (3) personal and tailored information is important but not guaranteed and (4) all-encompassing care to improve psychosocial functioning and QoL.

CONCLUSION

Patients with vaginal, vulvar, penile or anal cancer encounter a lack of awareness and knowledge about their rare cancer type, difficulties regarding communication and long-term changes in body image and sexuality. Awareness of symptoms should be raised and psychosocial care should be offered on a structural basis.

Rare cancer and return to work: experiences and needs of patients and (health care) professionals

PURPOSE

Patients with a rare cancer often face delays in their diagnostic and treatment trajectory, which may affect their work. In this study, we explored experiences and needs of: 1) patients with a rare cancer regarding return to work (RTW) and work retention, and 2) (health care) professionals (HCPs) regarding work-related support of patients with a rare cancer, throughout their disease trajectory.

METHODS

Semi-structured, in-depth interviews with working-age patients with a rare cancer (n = 16), and HCPs (n = 9) were conducted. During the interviews, a predefined topic list was used. Interviews were transcribed verbatim and analysed by means of thematic analysis.

RESULTS

In total, three themes emerged from the interviews: 1) Awareness in patients and HCPs as a first step towards work, 2) Being/becoming an expert is a tough job, and 3) Enhancing employability through early personalized guidance.

CONCLUSIONS

Patients with a rare cancer are confronted with uncertainties regarding work, due to an overall lack of knowledge and experience with these types of cancer. Raising awareness among patients, HCPs and employers about rare cancer and its implications, and providing timely individualized, supportive occupational care are required to improve rare cancer patients' ability to work.Implications for rehabilitationRecognizing and paying attention to the work-related consequences of a rare cancer diagnosis and its treatment is essential to facilitate rare cancer patients' occupational rehabilitation process.Multidisciplinary collaboration and involvement of HCPs specialized in rare cancer are required to provide suitable work-related support.A personalized approach is necessary to adequately address rare cancer patients' RTW and work retention needs.

The Efficacy of Immune Checkpoint Inhibitors in Rare Tumors: A Systematic Review of Published Clinical Trials

The immune checkpoint inhibitors (ICIs) entered treatment algorithms in most tumors. However, the data on the efficacy is limited in rare tumors with no phase III studies. We systemically reviewed the clinical trials evaluating the ICI efficacy in rare tumors and included a total of 47 clinical trials in this review. The ICIs demonstrated over 30% response rates in Merkel cell carcinoma and squamous cell carcinoma of the skin and became the standard of care. Additionally, the ICI efficacy was promising in thymic epithelial tumors and gestational trophoblastic neoplasia. In contrast, the ICI efficacy is limited in most sarcomas, germ cell tumors and low-grade neuroendocrine tumors. The ICI efficacy seemed to be improved with combinations targeting tumor microenvironment in sarcomas. The available evidence on ICI efficacy in rare tumors denote a need for better patient selection and novel combination strategies to improve outcomes.

Characteristics of Early Phase Clinical Trials for Rare Cancers: Insights From Interviews With Stakeholders

Background: Rare cancers occur with an incidence of no more than six cases per 100,000 people according to the definition used by the Surveillance of Rare Cancers in Europe project. For a variety of reasons (low prevalence, cytotoxicity), it is challenging to perform the necessary clinical studies to investigate the safety and efficacy of investigational medicines against such rare malignancies, reformulating even at the earliest stages of the drug development process. This article investigates the differences between phase I rare cancer trials performed in commercial (companies) and non-commercial settings (academic hospitals).

Materials and Methods: The differences were explored through the conduct of semi-structured interviews with three different stakeholder groups: representatives from academia (n = 7), representatives from companies (n = 4) and representatives from patient organizations (n = 4). All the interviews were transcribed verbatim and analyzed in NVivo using the framework method.

Results: According to the interviewees, the academic and commercial stakeholders collaborate in the majority of phase I rare cancer trials. In general, the commercial partner finances the trial, whereas academia is responsible for the execution of the study procedures. The average cost of undertaking these trials is difficult to estimate because it depends on what is specifically requested during the trial. The 3 + 3 study design remains the most widely used design and the use of expansion cohorts is controversial. With regard to the regulatory aspects of phase I rare cancer trials, it was expressed that a good regulatory framework facilitates the conduct of these studies, but that increased regulation and oversight also has drawbacks, e.g., differences in standards between different ethics committees, over interpretation of the rules, insufficient availability of qualified personnel and higher workloads. The patient organization representatives claimed that patients experience no differences in terms of accommodation, compensation and paperwork between the academic and commercial settings or the degree of follow-up. They also believed that the direct input of patients can bring added value to such studies not only with regard to the recruitment process and the feasibility of the study but also the legibility of the informed consent forms.

Conclusion: The growing need for first-in-man trials in rare malignancies needs to be highlighted, as difficult as they are to undertake and to co-develop, not only because rare cancer patients deserve an appropriate treatment, but also because these medicines represent the future of cancer therapy in the precision medicine era. Cooperation of commercial and academic sites are needed. Patient organizations need to be educated to take part in this process.

A framework for fibrolamellar carcinoma research and clinical trials

Fibrolamellar carcinoma (FLC), a rare, lethal hepatic cancer, occurs primarily in adolescents and young adults. Unlike hepatocellular carcinoma, FLC has no known association with viral, metabolic or chemical agents that cause cirrhosis. Currently, surgical resection is the only treatment demonstrated to achieve cure, and no standard of care exists for systemic therapy. Progress in FLC research illuminates a transition from an obscure cancer to one for which an interactive community seems poised to uncover fundamental mechanisms and initiate translation towards novel therapies. In this Roadmap, we review advances since the seminal discovery in 2014 that nearly all FLC tumours express a signature oncogene (DNAJB1-PRKACA) encoding a fusion protein (DNAJ-PKAc) in which the J-domain of a heat shock protein 40 (HSP40) co-chaperone replaces an amino-terminal segment of the catalytic subunit of the cyclic AMP-dependent protein kinase (PKA). Important gains include increased understanding of oncogenic pathways driven by DNAJ-PKAc; identification of potential therapeutic targets; development of research models; elucidation of immune mechanisms with potential for the development of immunotherapies; and completion of the first multicentre clinical trials of targeted therapy for FLC. In each of these key areas we propose a Roadmap for future progress.

Efficacy of Immune Checkpoint Inhibitors in Rare Tumours: A Systematic Review

Background

Rare cancers, as defined by the European Union, occur in fewer than 15 out of 100,000 people each year. The International Rare Cancer Consortium defines rare cancer incidence as less than six per 100,000 per year. There is a growing number of reports of the efficacy of immune checkpoint inhibitor (ICI) therapy in patients with rare tumours, and hence, we conducted a comprehensive review to summarise and analyse the available literature.

Methods

A literature search of PubMed was performed on January 31, 2021, using the following ICI names as keywords: ipilimumab, tremelimumab, cemiplimab, nivolumab, pembrolizumab, avelumab, atezolizumab, and durvalumab. Studies on patients with rare tumours who were being treated with ICIs were included. We plotted the overall response rate against the corresponding median survival across a variety of cancer types using linear regression.

Results

From 1,255 publications retrieved during the primary search, 62 publications were selected (with a total of 4,620 patients). Only four were randomised trials. A minority were first-line studies, while the remaining were studies in which ICIs were delivered as salvage therapy in pretreated patients. There was a good correlation between response rate and overall survival (Spearman R2 >0.9) in skin cancers, mesothelioma, and sarcomas.

Conclusions

Treatment of advanced-stage rare tumours with ICI therapy was found to be associated with significant activity in some orphan diseases (e.g., Merkel cell carcinoma) and hepatocellular carcinoma. Several ongoing prospective clinical trials will expand the knowledge on the safety and efficacy of ICI therapy in patients with these rare cancers.

Phase 2 study of pembrolizumab in patients with advanced rare cancers

Background

Patients with advanced rare cancers have poor prognosis and few treatment options. As immunotherapy is effective across multiple cancer types, we aimed to assess pembrolizumab (programmed cell death 1 (PD-1) inhibitor) in patients with advanced rare cancers.

Methods

In this open-label, phase 2 trial, patients with advanced rare cancers whose tumors had progressed on standard therapies, if available, within the previous 6 months were enrolled in nine tumor-specific cohorts and a 10th cohort for other rare histologies. Pembrolizumab 200 mg was administered intravenously every 21 days. The primary endpoint was non-progression rate (NPR) at 27 weeks; secondary endpoints were safety and tolerability, objective response rate (ORR), and clinical benefit rate (CBR).

Results

A total of 127 patients treated between August 15, 2016 and July 27, 2018 were included in this analysis. At the time of data cut-off, the NPR at 27 weeks was 28% (95% CI, 19% to 37%). A confirmed objective response (OR) was seen in 15 of 110 (14%) evaluable patients (complete response in one and partial response in 14). CBR, defined as the percentage of patients with an OR or stable disease ≥4 months, was 38% (n=42). Treatment was ongoing in 11 of 15 patients with OR at last follow-up. In the cohort with squamous cell carcinoma (SCC) of the skin, the NPR at 27 weeks was 36%, ORR 31%, and CBR 38%. In patients with adrenocortical carcinoma (ACC), NPR at 27 weeks was 31%, ORR 15%, and CBR 54%. In the patients with carcinoma of unknown primary (CUP), NPR at 27 weeks was 33%, ORR 23%, and CBR 54%. In the paraganglioma–pheochromocytoma cohort, NPR at 27 weeks was 43%, ORR 0%, and CBR 75%. Treatment-related adverse events (TRAEs) occurred in 66 of 127 (52%) patients, and 12 (9%) had grade ≥3 TRAEs. The most common TRAEs were fatigue (n=25) and rash (n=17). There were six deaths, all of which were unrelated to the study drug.

Conclusions

The favorable toxicity profile and antitumor activity seen in patients with SCC of skin, ACC, CUP, and paraganglioma–pheochromocytoma supports further evaluation of pembrolizumab in this patient population.

Trial registration number

NCT02721732

Differences in health care experiences between rare cancer and common cancer patients: results from a national cross-sectional survey

Background

Patients with rare cancers face challenges in the diagnostic and treatment phase, and in access to clinical expertise. Since studies on health care experiences of these patients in comparison to patients with more common cancers are scarce, we aimed to explore these differences.

Methods

Data were cross-sectionally collected among (former) adult cancer patients through a national online survey in the Netherlands (October 2019). Descriptive statistics were reported and subgroups (rare vs. common patients) were compared.

Results

In total, 7343 patients (i.e., 1856 rare and 5487 common cancer patients) participated. Rare cancer patients were more often diagnosed and treated in different hospitals compared to common cancer patients (67% vs. 59%, p < 0.001). Rare cancer patients received treatment more often in a single hospital (60% vs. 57%, p = 0.014), but reported more negative experiences when treated in multiple hospitals than common cancer patients (14% vs. 9%, p < 0.001). They also more often received advise from their physician about the hospital to go to for a second opinion (50% vs. 36%, p < 0.001), were more likely to choose a hospital specialized in their cancer type (33% vs. 22%, p < 0.001), and were more willing to travel as long as necessary to receive specialized care than common cancer patients (55% vs. 47%, p < 0.001).

Conclusions

Rare and common cancer patients differ in their health care experiences. Health care for rare cancer patients can be further improved by proper referral to centers of expertise and building a clinical network specifically for rare cancers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-01886-2.

Supportive care needs of patients living with an extremely rare and unpredictable cancer: The Epithelioid Haemangioendothelioma patient experience

OBJECTIVE

Epithelioid haemangioendothelioma (EHE) is an ultrarare vascular sarcoma with an incidence of <1/million/year and a large clinical heterogeneity. Data on supportive care needs of rare cancer patients are scarce. This study aimed to investigate the level of supportive care needs of EHE patients and its association with sociodemographic, clinical and symptom burden characteristics.

METHODS

We present secondary data of a cross-sectional questionnaire study involving EHE patients recruited from the international EHE Facebook group. Data were collected using the web-based PROFILES registry. Unmet needs were measured with Supportive Care Needs Survey Short Form (SCNS-SF34).

RESULTS

115 EHE patients from 20 countries completed the online questionnaire. Mean level of supportive care needs was 68.4 (range 34-170), with the highest mean score on the psychological domain. Supportive care needs were associated with age, disease stage, years since diagnosis and number of tumour locations. Highly symptomatic patients (33%) reported more supportive care needs than patients with low or intermediate symptom burden.

CONCLUSION

Supportive care needs were found in all domains, highest in the psychological domain, and were associated with sociodemographic, clinical and symptom burden characteristics. Adequate and tailored supportive care should be offered especially to highly symptomatic EHE patients.

Radiomics analysis for predicting pembrolizumab response in patients with advanced rare cancers

BACKGROUND

We present a radiomics-based model for predicting response to pembrolizumab in patients with advanced rare cancers.

METHODS

The study included 57 patients with advanced rare cancers who were enrolled in our phase II clinical trial of pembrolizumab. Tumor response was evaluated using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and immune-related RECIST (irRECIST). Patients were categorized as 20 "controlled disease" (stable disease, partial response, or complete response) or 37 progressive disease). We used 3D-slicer to segment target lesions on standard-of-care, pretreatment contrast enhanced CT scans. We extracted 610 features (10 histogram-based features and 600 second-order texture features) from each volume of interest. Least absolute shrinkage and selection operator logistic regression was used to detect the most discriminatory features. Selected features were used to create a classification model, using XGBoost, for the prediction of tumor response to pembrolizumab. Leave-one-out cross-validation was performed to assess model performance.

FINDINGS

The 10 most relevant radiomics features were selected; XGBoost-based classification successfully differentiated between controlled disease (complete response, partial response, stable disease) and progressive disease with high accuracy, sensitivity, and specificity in patients assessed by RECIST (94.7%, 97.3%, and 90%, respectively; p<0.001) and in patients assessed by irRECIST (94.7%, 93.9%, and 95.8%, respectively; p<0.001). Additionally, the common features of the RECIST and irRECIST groups also highly predicted pembrolizumab response with accuracy, sensitivity, specificity, and p value of 94.7%, 97%, 90%, p<0.001% and 96%, 96%, 95%, p<0.001, respectively.

CONCLUSION

Our radiomics-based signature identified imaging differences that predicted pembrolizumab response in patients with advanced rare cancer.

INTERPRETATION

Our radiomics-based signature identified imaging differences that predicted pembrolizumab response in patients with advanced rare cancer.

Travel burden and clinical presentation of retinoblastoma: analysis of 1024 patients from 43 African countries and 518 patients from 40 European countries

BACKGROUND

The travel distance from home to a treatment centre, which may impact the stage at diagnosis, has not been investigated for retinoblastoma, the most common childhood eye cancer. We aimed to investigate the travel burden and its impact on clinical presentation in a large sample of patients with retinoblastoma from Africa and Europe.

METHODS

A cross-sectional analysis including 518 treatment-naïve patients with retinoblastoma residing in 40 European countries and 1024 treatment-naïve patients with retinoblastoma residing in 43 African countries.

RESULTS

Capture rate was 42.2% of expected patients from Africa and 108.8% from Europe. African patients were older (95% CI -12.4 to -5.4, p<0.001), had fewer cases of familial retinoblastoma (95% CI 2.0 to 5.3, p<0.001) and presented with more advanced disease (95% CI 6.0 to 9.8, p<0.001); 43.4% and 15.4% of Africans had extraocular retinoblastoma and distant metastasis at the time of diagnosis, respectively, compared to 2.9% and 1.0% of the Europeans. To reach a retinoblastoma centre, European patients travelled 421.8 km compared to Africans who travelled 185.7 km (p<0.001). On regression analysis, lower-national income level, African residence and older age (p<0.001), but not travel distance (p=0.19), were risk factors for advanced disease.

CONCLUSIONS

Fewer than half the expected number of patients with retinoblastoma presented to African referral centres in 2017, suggesting poor awareness or other barriers to access. Despite the relatively shorter distance travelled by African patients, they presented with later-stage disease. Health education about retinoblastoma is needed for carers and health workers in Africa in order to increase capture rate and promote early referral.

Impact of rarity on Canadian oncology health technology assessment and funding

OBJECTIVES

The pan-Canadian Oncology Drug Review (pCODR) evaluates new cancer drugs for public funding recommendations. While pCODR's deliberative framework evaluates overall clinical benefit and includes considerations for exceptional circumstances, rarity of indication is not explicitly addressed. Given the high unmet need that typically accompanies these indications, we explored the impact of rarity on oncology HTA recommendations and funding decisions.

METHODS

We examined pCODR submissions with final recommendations from 2012 to 2017. Incidence rates were calculated using pCODR recommendation reports and statistics from the Canadian Cancer Society. Indications were classified as rare if the incidence rate was lower than 1/100,000 diagnoses, a definition referenced by the Canadian Agency for Drugs and Technologies in Health. Each pCODR final report was examined for the funding recommendation/justification, level of supporting evidence (presence of a randomized control trial [RCT]), and time to funding (if applicable).

RESULTS

Of the ninety-six pCODR reviews examined, 16.6 percent were classified as rare indications per above criteria. While the frequency of positive funding recommendations were similar between rare and nonrare indication (78.6 vs. 75 percent), rare indications were less likely to be presented with evidence from RCT (50 vs. 90 percent). The average time to funding did not differ significantly across provinces.

CONCLUSION

Rare indications appear to be associated with weaker clinical evidence. There appears to be no association between rarity, positive funding recommendations, and time to funding. Further work will evaluate factors associated with positive recommendations and the real-world utilization of funded treatments for rare indications.

Rare cancers in Canada, 2006-2016: A population-based surveillance report and comparison of different methods for classifying rare cancers

BACKGROUND

The cumulative burden from rare cancers has not been adequately explored in Canada. This analysis aims to characterize the occurrence of rare cancers among Canadians and estimate the probability of being diagnosed with a rare cancer among cancer patients with different demographic characteristics.

METHODS

The Canadian Cancer Registry was used for this analysis. Cancer types were classified in three ways: using the SEER site recode scheme; by histology group; and by site/histology group. The age-standardized incidence rate (ASIR) and 95 % confidence intervals (CI) for each cancer type was estimated for diagnoses from 2006 to 2016. Two ASIR thresholds were used to classify cancers as rare:6/100,000/year and 15/100,000/year. Log-binomial regression was used to estimate the adjusted probability of having a rare cancer among those with cancer by age, sex and geographic region.

RESULTS

Using the 6/100,000/year threshold, the incidence proportion (IP) of rare cancers ranged from 9.7 %(95 %CI:9.6,9.7 %)-17.0 %(95 %CI:16.9,17.0 %), and ranged from 19.2 %(95 %CI:19.1,19.3 %)-52.5 %(95 %CI:52.0,53.0 %) using the <15/100,000/year threshold. The adjusted probability of being diagnosed with a rare cancer was highest among those aged ≤19 years. There was higher concordance in estimates of the burden of rare cancers across methods to classify cancer types when the lower incidence rate threshold was used to define rare cancers.

INTERPRETATION

This analysis yielded evidence that rare cancers comprise a substantial proportion of annual cancer diagnoses among Canadians. Findings from this analysis point to using a lower incidence rate threshold, to generate estimates of the burden of rare cancers that are robust to different cancer classification schemes.

Travel burden associated with rare cancers: The example of Merkel cell carcinoma

BACKGROUND

There are limited data on the travel burden for cancer patients with rare tumor types, such as Merkel cell carcinoma (MCC).

OBJECTIVE

The objective of this study was to understand the travel burden of MCC patients.

METHODS

This study used data from an MCC registry at the Seattle Cancer Care Alliance (SCCA). All MCC patients enrolled at SCCA with a valid 3-digit ZIP code were included. Patients were followed up from January 1, 2012 until their last follow-up, death, or end of data (January 1, 2017). Travel burden was measured by one-way travel distance to SCCA from each patient's 3-digit ZIP code. Patient demographics, tumor characteristics, and follow-up visit were evaluated and stratified by one-way driving distance of ≤300 and >300 miles.

RESULTS

A total of 391 MCC patients were included (68% men, mean age = 67 years [±SD = ±11 years], 67% residing in the West, and 70% white). At diagnosis, 53% of the patients had Stage III or IV MCC. Mean one-way distance traveled by patients was 1,137 (median: 813) miles, and 57% of patients traveled >300 miles. Compared to patients who traveled ≤300 miles, those who traveled >300 miles were more likely to be <70 years old (46% vs 65%; P < 0.001), were diagnosed with advanced stage (III or IV) MCC (46% vs 59%; P = 0.01), had shorter follow-up in the cancer registry (mean: 509 vs 212 days; P < 0.001), and had fewer visits during follow-up (mean: 5.2 vs 2.5; P < 0.001).

CONCLUSIONS

In this single cancer center study, the majority of MCC patients trav-eled long distances to receive expert care. Longer travel distances appeared to be associated with younger age, a more advanced stage of cancer at study entry and fewer in-clinic visits, suggesting that travel burden may impact timely and adequate patient care for this rare cancer.

Evidence-based data and rare cancers: The need for a new methodological approach in research and investigation

Rare cancers are not so rare, their incidence is increasing and, as a group, they have worse survival than the common cancers. These factors emphasise the societal need to ensure sufficient focus on research into their biological basis, aetiological factors, new more effective therapies and organisation of healthcare to improve access to best practice and innovation. Accuracy of diagnosis is one of the first hurdles to be overcome, with around one third of tumours being reclassified - by type or risk group - when subject to a centralised pathology review process. Timely access to appropriate expert knowledge is a second challenge for patients - in Europe this is being addressed by the establishment of European Reference Networks (ERNs) as part of the EU cross border healthcare initiative. There are ERNs for adult solid and haematological cancers and childhood cancers, all of which are individually rare. These ERNs will facilitate creation of large databases of rare tumours that will incorporate knowledge of their molecular features and build an evidence base for the effectiveness of innovative, biology-directed therapies. With an increasing focus on 'real world' outcome data, research methodologies are evolving, to include randomised registry trials and data linkage approaches that exploit the ever-richer information held on patients in routine health care data. The inclusion of genomic analysis into cancer diagnosis, treatment and risk prediction raises many issues for the conduct of clinical research and cohort studies and personal data sharing. Sophisticated means of pseudonymisation, together with full involvement of affected and 'at risk' patients, are supporting novel research designs and access to data that will continue to build the evidence base to improve outcomes for patients with rare cancers.

The burden of rare cancers in the United States

There are limited published data on the burden of rare cancers in the United States. By using data from the North American Association of Central Cancer Registries and the Surveillance, Epidemiology, and End Results program, the authors provide information on incidence rates, stage at diagnosis, and survival for more than 100 rare cancers (defined as an incidence of fewer than 6 cases per 100,000 individuals per year) in the United States. Overall, approximately 20% of patients with cancer in the United States are diagnosed with a rare cancer. Rare cancers make up a larger proportion of cancers diagnosed in Hispanic (24%) and Asian/Pacific Islander (22%) patients compared with non-Hispanic blacks (20%) and non-Hispanic whites (19%). More than two-thirds (71%) of cancers occurring in children and adolescents are rare cancers compared with less than 20% of cancers diagnosed in patients aged 65 years and older. Among solid tumors, 59% of rare cancers are diagnosed at regional or distant stages compared with 45% of common cancers. In part because of this stage distribution, 5-year relative survival is poorer for patients with a rare cancer compared with those diagnosed with a common cancer among both males (55% vs 75%) and females (60% vs 74%). However, 5-year relative survival is substantially higher for children and adolescents diagnosed with a rare cancer (82%) than for adults (46% for ages 65-79 years). Continued efforts are needed to develop interventions for prevention, early detection, and treatment to reduce the burden of rare cancers. Such discoveries can often advance knowledge for all cancers. CA Cancer J Clin 2017. © 2017 American Cancer Society. CA Cancer J Clin 2017;67:261-272. © 2017 American Cancer Society.