Do radiation-associated soft tissue sarcomas have the same prognosis as sporadic soft tissue sarcomas?

Radiation-induced Osteosarcoma in the Thoracic Cavity 28 Years after Irradiation for a Benign Disease: An Autopsy Case

A 60-year-old man with a history of radiation therapy 28 years ago for a benign disease (an aneurysmal bone cyst) was admitted with dyspnea and dysphagia. Computed tomography showed an 8-cm tumor invading the trachea and esophagus. His condition declined rapidly, and he died on day 27 of hospitalization. Autopsy revealed radiation-induced osteosarcoma. Radiation-induced sarcoma can develop even after radiotherapy for benign diseases, in which case the latency period might be longer. Furthermore, the prognosis depends on the location of the resectable tumor. Therefore, longer-term internal imaging follow-up should be performed after radiotherapy for benign diseases to detect early-stage sarcoma.

SEOM-GEIS Spanish clinical guidelines for the management of soft‑tissue sarcomas (2024)

Soft-tissue sarcomas are rare, diverse malignant tumors of mesenchymal origin, requiring diagnosis and treatment by a specialized multidisciplinary team. Initial assessment includes radiology and biopsy, followed by wide surgical resection with clear margins for localized cases. Radiotherapy is recommended for large, deep, high-grade tumors or after incomplete resection, while perioperative chemotherapy may be considered for high-risk cases. In oligometastatic disease, combining local and systemic therapies is an option. Anthracycline-based chemotherapy is the first-line treatment in advanced disease, though other drugs show efficacy in certain subtypes. Given the limited options, enrolling in clinical trials is advised for patients needing further treatment.

Radiation-induced osteosarcoma of the frontoparietal calvaria 6 years after oligodendroglioma treatment: illustrative case

BACKGROUND

Radiation-induced sarcoma (RIS) is an exceptionally rare occurrence following radiation therapy, and manifestation usually occurs after a several-year latency period. Herein, the authors report the development of a radiation-induced osteosarcoma of the frontoparietal calvaria following treatment for an oligodendroglioma in an 84-year-old woman.

OBSERVATIONS

The patient had been diagnosed with a grade III anaplastic oligodendroglioma when she was 78 years old. She had undergone resection and subsequent chemoradiation therapy for treatment of the tumor. In the following years, she experienced progressive neurological decline, which was complicated by multiple ischemic strokes and seizure episodes. When she was approximately 84 years of age, a small mass was noted overlying the previous craniotomy site during examination. Several months later, approximately 5 years after chemoradiation therapy, she presented to the emergency department with a suspected stroke. Examination revealed that the mass had rapidly grown and was pressing into the intracranial space. She underwent craniotomy, and specimens were taken. Pathological analysis demonstrated a high-grade osteosarcoma.

LESSONS

Despite the lesion's rarity, suspicion for RIS should be raised with the rapid growth of a mass at the site of previous radiotherapy. Furthermore, it is especially important to carefully monitor vulnerable patients who may not be able to recognize or report the development of a growing mass. https://thejns.org/doi/10.3171/CASE24535.

UK guidelines for the management of soft tissue sarcomas

Soft tissue sarcomas (STS) are rare tumours arising in mesenchymal tissues and can occur almost anywhere in the body. Their rarity, and the heterogeneity of subtype and location, means that developing evidence-based guidelines is complicated by the limitations of the data available. This makes it more important that STS are managed by expert multidisciplinary teams, to ensure consistent and optimal treatment, recruitment to clinical trials, and the ongoing accumulation of further data and knowledge. The development of appropriate guidance, by an experienced panel referring to the evidence available, is therefore a useful foundation on which to build progress in the field. These guidelines are an update of the previous versions published in 2010 and 2016 [1, 2]. The original guidelines were drawn up by a panel of UK sarcoma specialists convened under the auspices of the British Sarcoma Group (BSG) and were intended to provide a framework for the multidisciplinary care of patients with soft tissue sarcomas. This iteration of the guidance, as well as updating the general multidisciplinary management of soft tissue sarcoma, includes specific sections relating to the management of sarcomas at defined anatomical sites: gynaecological sarcomas, retroperitoneal sarcomas, breast sarcomas, and skin sarcomas. These are generally managed collaboratively by site specific multidisciplinary teams linked to the regional sarcoma specialist team, as stipulated in the recently published sarcoma service specification [3]. In the UK, any patient with a suspected soft tissue sarcoma should be referred to a specialist regional soft tissues sarcoma service, to be managed by a specialist sarcoma multidisciplinary team. Once the diagnosis has been confirmed using appropriate imaging and a tissue biopsy, the main modality of management is usually surgical excision performed by a specialist surgeon, combined with pre- or post-operative radiotherapy for tumours at higher risk for local recurrence. Systemic anti-cancer therapy (SACT) may be utilised in cases where the histological subtype is considered more sensitive to systemic treatment. Regular follow-up is recommended to assess local control, development of metastatic disease, and any late effects of treatment.

A case of undifferentiated pleomorphic rectal sarcoma occurring after radiation exposure

A 72 year-old man was referred to our hospital for a detailed examination of a recurrent rectal polyp. He had past histories of surgery and radiation therapy for prostate cancer at the age of 66 and endoscopic excision of a rectal polyp at the age of 70. Colonoscopy revealed a semi-pedunculated lesion surrounded by friable mucosa, which was positive under positron-emission tomography-computed tomography. Histopathological examination of the endoscopically excised polyp revealed proliferation of atypical cells, characterized by strong pleomorphic or spindle morphology, which was immunohistochemically compatible with undifferentiated pleomorphic sarcoma. We diagnosed this case as sarcoma presumably associated with radiation proctitis.

Genitourinary toxicity after pelvic radiation: Prospective review of complex urological presentations

Objective

Recent randomised controlled trials underestimated the incidence of genitourinary (GU) complications occurring more than 5 years following pelvic radiotherapy. This study aimed to determine the burden of treatment at a single institution from late GU complications after pelvic radiotherapy.

Methods

A prospective study of all presentations for GU complications following pelvic radiotherapy at a tertiary urology department between November 2018 and November 2019 was performed. Subgroup analyses was performed on patients with prostate cancer (PCa) with late toxicity to compare patient demographics, radiotherapy, complications, and management factors.

Results

There were 117 hospital encounters involving 46 patients with a 56.4% repeat encounter rate. Patients with PCa were the predominant group (n=39, 84.8%). External beam radiotherapy was the most common treatment modality (n=41, 89.1%). The median time from radiotherapy to encounter was 8 (range 0-23) years. Radiation-induced haemorrhagic cystitis was the most common presentation (n=70, 59.8%). Forty-four (42.7%) encounters for GU toxicity were managed operatively and 33 (32.0%) involved a non-operative procedure. Nine patients required packed red cell transfusion, with a total of 154 units transfused. Patients with PCa who presented with late GU toxicity had higher median Radiotherapy Oncology Group grades (p=0.020), proportion of emergency admissions (p=0.047), and frequency of clot urinary retention (p<0.001).

Conclusion

There is a high burden of elective and emergency urology workload attributed to late pelvic radiation toxicity. Late GU toxicity occurring ≥5 years after radiotherapy is common and often more severe.

Genomic analysis of an aggressive hepatic leiomyosarcoma case following treatment for hepatocellular carcinoma

A 70-year-old man undergoing treatment for immunoglobulin G4-related disease developed a liver mass on computed tomography during routine imaging examination. The tumor was located in the hepatic S1/4 region, was 38 mm in size, and showed arterial enhancement on dynamic contrast-enhanced computed tomography. We performed a liver biopsy and diagnosed moderately differentiated hepatocellular carcinoma. The patient underwent proton beam therapy. The tumor remained unchanged but enlarged after 4 years. The patient was diagnosed with hepatocellular carcinoma recurrence and received hepatic arterial chemoembolization. However, 1 year later, the patient developed jaundice, and the liver tumor grew in size. Unfortunately, the patient passed away. Autopsy revealed that the tumor consisted of spindle-shaped cells exhibiting nuclear atypia and a fission pattern and tested positive for α-smooth muscle actin and vimentin. No hepatocellular carcinoma components were observed, and the patient was pathologically diagnosed with hepatic leiomyosarcoma. Next-generation sequencing revealed somatic mutations in CACNA2D4, CTNNB1, DOCK5, IPO8, MTMR1, PABPC5, SEMA6D, and ZFP36L1. Based on the genetic mutation, sarcomatoid hepatocarcinoma was the most likely pathogenesis in this case. This mutation is indicative of the transition from sarcomatoid hepatocarcinoma to hepatic leiomyosarcoma.

Clinicopathological and genetic characterization of radiotherapy-induced undifferentiated pleomorphic sarcoma following breast cancer: a case series of three tumors and comprehensive literature review

AIMS

Compared to primary breast sarcoma (BSs), radiotherapy-induced sarcoma (RIS) is a less frequent type of secondary breast sarcoma. Undifferentiated pleomorphic sarcoma (UPS) is an even rarer occurrence within the RIS category. This study aimed to present the clinicopathologic and molecular features of breast radiotherapy-induced UPS.

METHODS

A retrospective study was conducted at the Third Affiliated Hospital of Soochow University to analyze three patients with radiation-induced undifferentiated pleomorphic sarcoma (UPS) following breast cancer, spanning from 2006 to 2023. The clinical and pathological variables were extracted from the medical records, while immunohistochemistry was employed to analyze the immunophenotypes of these tumors. Genomic characteristics were assessed through DNA and RNA sequencing techniques. Another 15 cases from the literature were also reviewed to better characterize the tumor.

RESULTS

The affected areas encompass the chest wall and breasts, with an incubation period ranging from 6 to 17 years. The tumor cells exhibit pleomorphism and demonstrate a high degree of pathological mitosis. Notably, two cases displayed an accelerated disease progression, characterized by recurrent tumors and metastases occurring within short intervals of 48 and 7 months respectively subsequent to the initial diagnosis. The two prevailing identified genes were TP53 (2/3, 66.7%) and RB1 (1/3, 33.3%). Through analysis of somatic copy number variation (CNV), it was discovered that two oncogenes, MCL1 (1/3, 33.3%) and MYC (1/3, 33.3%), had experienced gains in CNV. The Tumor Mutational Burden (TMB) values for case 1, case 2, and case 3 were 5.9 mut/Mb, 1.0 mut/Mb, and 3.0 mut/Mb, respectively. Moreover, the analysis of RNA-NGS (next-generation sequencing) revealed the presence of a novel gene fusion, named COL3A1-GULP1, in case 2.

CONCLUSIONS

Based on our thorough analysis of research findings and previous reports, it is evident that radiotherapy-induced UPS exhibits a highly diverse and frequently severe clinical and biological behavior. Identifying tumor formation using genome sequencing can help understand its biological behavior and determine personalized treatments.

Outcomes of non-angiosarcoma radiation-associated soft tissue sarcomas of the chest

BACKGROUND

Radiation-associated soft tissue sarcomas (RA-STS) are rare complications of patients receiving radiation therapy (RT) and are generally associated with a poor prognosis. Most of the literature surrounding RA-STS of the chest is centered on angiosarcoma. Therefore, we aim to document the management and outcome of patients with non-angiosarcoma RA-STS of the chest.

METHODS

We reviewed 17 patients (all female, median age 65 years) diagnosed with RA-STS. The most common primary malignancy was breast carcinoma (n = 15), with a median RT dose of 57.9 Gy. All patients underwent surgical resection; five patients (29%) received radiotherapy; and five patients (29%) received peri-operative chemotherapy.

RESULTS

The 5-year local recurrence and metastatic-free survival were 61% and 60%, while the 5-year disease-specific survival was 53%. Local recurrence was associated with death due to disease (HR 9.06, p = 0.01). Complications occurred in nine of patients, most commonly due to a wound complication (n = 7). At the most recent follow-up, the median Musculoskeletal Tumor Society Score was 63%.

CONCLUSION

RA-STS involving the chest wall are aggressive tumors with a high risk of local relapse and death due to disease. Local recurrence was associated with death due to disease; as such, we recommend aggressive surgical management with evaluation for adjuvant therapies.

[Radiation-induced sarcoma in patients with nasopharyngeal carcinoma: a single-institution retrospective study]

Objective:To analyze the clinical features, treatment methods and prognosis of radiation-induced sarcoma（RIS） of the head and neck after radiotherapy for nasopharyngeal carcinoma（NPC）, and explore its treatment strategies. Methods:A retrospective analysis was conducted on RIS patients after radiotherapy for NPC in the People's Hospital of Guangxi Zhuang Autonomous Region from January 2013 to October 2022. The time of onset, lesion location, pathological subtypes, imaging features and treatment outcomes were described, and the median survival time was statistically analyzed through follow-up. Results:This study included 10 patients with an interval of 2-27 years between NPC and RIS. The nasopharynx was the more common site of RIS, and osteosarcoma was the main pathological type. The median overall survival was 18 months. The median survival was 40 months in the surgery combined with the chemotherapy group, and 12 months in the surgery alone group. The 1-and 2-year cumulative survival rates were 48% and 36%, respectively. Prognostic analysis showed that gender, age of onset, time of sarcoma onset after radiotherapy and treatment methods might not be influencing factors for prognosis, and osteosarcomas presented a poorer prognosis than other pathological types. Conclusion:RIS is one of the most severe long-term adverse effects in patients with NPC. The prognosis of RIS is poor, and complete surgical resection of the tumor can improve patient survival rates. In cases where complete surgical resection is challenging, radiotherapy or chemotherapy may offer some improvement in tumor control.

Primary orbital sarcoma in adults: a case series with emphasis on post-irradiation sarcoma

PURPOSE

To describe a series of eight adult patients with primary orbital sarcoma and to review the existing literature on orbital sarcoma and post-irradiation sarcoma.

METHODS

Report of eight cases and literature review.

RESULTS

We report eight cases of primary orbital sarcoma, three of which were radiation-induced. Only one patient had a history of retinoblastoma. The most common presentations were painful proptosis and reduced vision. Most tumours arose in the extraconal compartment. The overall median age at diagnosis was 50 years. The pathology comprised a diverse group of tumours. Treatment and outcome varied between patients and their clinical circumstances.

CONCLUSIONS

Adult primary orbital sarcomas are rare. They can comprise a variety of tumour types and are difficult to treat. Irradiation is a significant risk factor, and the incidence of post-irradiation sarcoma of the orbit may be increasing due to the widespread use of radiotherapy and improved survival of patients with cancer. Post-irradiation sarcoma should be considered in the differential diagnosis of an orbital space-occupying lesion in a patient with a history of radiotherapy.

Outcome improvement with chemotherapy and radiotherapy in primary, localized, radiation-associated angiosarcoma of the breast region: a retrospective case series analysis

BACKGROUND

We report on a series of consecutive patients with localized radiation-associated angiosarcoma (RAAS) of the breast region (BR) treated at two Italian sarcoma reference centers.

MATERIALS AND METHODS

We retrospectively reviewed all cases of primary, localized, resectable RAAS of the BR, treated at one of the two participating institutions from 2000 to 2019. Relapse-free survival (RFS) and overall survival (OS) were calculated. The prognostic role of several variables was investigated. A propensity score matched (PSM) analysis was carried out.

RESULTS

Eighty-four patients were retrospectively identified. Nineteen out of 84 patients (22.6%) were pretreated with an anthracycline-based regimen for previous cancer. All patients but one underwent surgery, with 37/84 (44.1%) receiving surgery alone and 46/84 (54.8%) a multimodal approach: 18/84 (21.4%) received radiation therapy (RT) and 46/84 (54.9%) received chemotherapy. An anthracycline-based regimen was used in 10/84 patients (11.9%), while a gemcitabine-based regimen was used in 33/84 (39.3%). With a median follow-up of 51 months (interquartile range: 30-126 months), 36/84 patients (42.9%) relapsed and 35/84 patients (41.7%) died (8/84, 9.5% in the lack of metastatic disease). Five-year OS and 5-year RFS were 57% [95% confidence interval (CI) 43% to 68%] and 52% (95% CI 39% to 63%), respectively. Both (neo)adjuvant RT and chemotherapy were associated with better RFS [hazard ratio (HR) 0.25, 95% CI 0.08-0.83; HR 0.45, 95% CI 0.23-0.89] with a trend towards a better OS (HR 0.51, 95% CI 0.18-1.46; HR 0.60, 95% CI 0.29-1.24). Gemcitabine-based regimens seemed to perform better (HR 4.28, 95% CI 1.29-14.14). PSM analysis retained the above results.

CONCLUSIONS

This retrospective study supports the use of (neo)adjuvant RT and chemotherapy, in primary, localized resectable RAAS of the BR. An effort to prospectively validate the role of (neo)adjuvant RT and chemotherapy is warranted.

Risk of thoracic soft tissue sarcoma after breast cancer radiotherapy: a population-based cohort study in Osaka, Japan

Postoperative radiotherapy for breast cancer reportedly increases the risk of thoracic soft tissue sarcomas, particularly angiosarcomas; however, the risk in the Japanese population remains unknown. Therefore, this study aimed to investigate the incidence of thoracic soft tissue sarcoma among patients with breast cancer in Japan and determine its association with radiotherapy. This retrospective cohort study used data from the population-based cancer registry of the Osaka Prefecture. The inclusion criteria were female sex, age 20-84 years, diagnosis of breast cancer between 1990 and 2010, no supraclavicular lymph node or distant metastasis, underwent surgery and survived for at least 1 year. The primary outcome was the occurrence of thoracic soft tissue sarcomas 1 year or later after breast cancer diagnosis. Among the 13 762 patients who received radiotherapy, 15 developed thoracic soft tissue sarcomas (nine angiosarcomas and six other sarcomas), with a median time of 7.7 years (interquartile range, 4.0-8.6 years) after breast cancer diagnosis. Among the 27 658 patients who did not receive radiotherapy, four developed thoracic soft tissue sarcomas (three angiosarcomas and one other sarcoma), with a median time of 11.6 years after diagnosis. The 10-year cumulative incidence was higher in the radiotherapy cohort than in the non-radiotherapy cohort (0.087 vs. 0.0036%, P < 0.001). Poisson regression analysis revealed that radiotherapy increased the risk of thoracic soft tissue sarcoma (relative risk, 6.8; 95% confidence interval, 2.4-24.4). Thus, although rare, breast cancer radiotherapy is associated with an increased risk of thoracic soft tissue sarcoma in the Japanese population.

Clinical Characteristics, Patterns of Care, and Treatment Outcomes of Radiation-Associated Sarcomas

Radiation-associated sarcomas (RASs) are rare tumors with limited contemporary data to inform prognostication and management. We sought to identify the clinical presentation, patterns of care, and prognostic factors of RASs. RAS patients treated at a single institution from 2015 to 2021 were retrospectively reviewed for clinicopathologic variables, treatment strategies, and outcomes. Thirty-eight patients were identified with a median follow-up of 30.5 months. The median age at RAS diagnosis was 68.4 years (27.9-85.4), with a median latency from index radiotherapy (RT) of 9.1 years (3.7-46.3). RAS histologies included angiosarcoma (26%), undifferentiated pleomorphic sarcoma (21%), and osteosarcoma (18%). Most were high-grade (76%). Genomic profiling revealed low tumor mutational burden, frequent inactivating TP53 mutations (44%), CDKN2A deletions (26%), and MYC amplifications (22%), particularly in breast angiosarcomas. Of 38 patients, 33 presented with localized disease, 26 of whom were treated with curative intent. Overall, the median progression-free survival (PFS) was 9.5 months (1.4-34.7), and the overall survival (OS) was 11.1 months (0.6-31.6). Patients with localized vs. metastatic RASs had a longer PFS (HR, 3.0 [1.1-8.5]; p = 0.03) and OS (HR, 3.0 [1.04-8.68]; p = 0.03). Among localized RAS patients, high grade was associated with shorter OS (HR, 4.6 [1.04-20.30]; p = 0.03) and resection with longer OS (mean 58.8 vs. 6.1 months, HR, 0.1 [0.03-0.28]; p < 0.001). Among patients undergoing resection, negative margins were associated with improved OS (mean 71.0 vs. 15.5 months, HR, 5.1 [1.4-18.2]; p = 0.006). Patients with localized disease, particularly those undergoing R0 resection, demonstrated significantly better outcomes. Novel strategies are urgently needed to improve treatment outcomes in this challenging group of diseases.

Leiomyosarcoma of the rectum: A systematic review of recent literature

Leiomyosarcomas (LMSs) are rare tumors originating from the muscular layer. We performed a literature review of cases of confirmed rectal leiomyosarcomas (rLMSs) to clarify the history of such an infrequent tumor arising at such an uncommon location. In this research local recurrence was related to poorly differentiated rLMS and no other association between recurrence and any criteria was found. Concerning overall survival (OS), rLMS patients developing recurrence presented shorter longevity compared with the group without.

A distal ileum malignant peripheral nerve sheath tumour after abdominal radiation therapy: case report of a rare tumour

Malignant peripheral nerve sheath tumours (MPNSTs) are malignant tumours arising from a peripheral nerve or displaying nerve sheath differentiation. Most MPNSTs are found on the head, body trunk and extremities, whereas cases in the gastrointestinal are extremely rare. About half arise in neurofibromatosis type 1 patients and 10% arise post-irradiation. This is probably the first small bowel MPNST post-radiation therapy case reported. A 72-year-old female who received radiotherapy 30 years ago for cervical cancer was admitted with progressive abdominal pain and weight loss. Computed tomography revealed a mass with inhomogeneous enhancement in the lumen of the small intestine. Tumour excision was performed with ileocecal and sigmoid colon resection due to suspicion for peripheral tissue invasion. Histopathological examination revealed spindle-shaped cells with focal cartilage differentiation. Together with immunochemistry stain showing complete loss of H3K27me3, a final diagnosis of MPNST was made. The patient is presently under regular follow-ups, and has remained disease-free for 24 months.

Gender Differences in Soft Tissue and Bone Sarcoma: A Narrative Review

Sarcomas, uncommon malignancies, stem from mesenchymal tissues, distinct from epithelial tissues, originating in the embryonic mesodermal layer. These sarcomas have been categorized as either bone or soft tissue sarcomas, depending on their originating tissue. The majority of sarcomas occur sporadically with their etiology being unknown, but there are several, well-established genetic predisposition syndromes and some environmental exposures associated with specific sarcomas. Recently, many studies have shown that sarcomas, in analogy with colorectal, skin, head and neck, esophageal, lung, and liver carcinomas, also have a male sex predilection. Significant gender differences have already been observed in childhood sarcomas. Among the tumors strongly associated with the male sex, childhood sarcomas have been identified as being particularly sensitive to the biological differences between the sexes, with special regard to soft tissue sarcomas. As the biological mechanisms underlying the sex differences in the incidence of soft tissue sarcomas remain largely unexplored, this review aims to highlight the factors underlying these differences to inform prevention and treatment.

A rare case of radiation-induced breast angiosarcoma: a case report

We describe a rare case of a 77-year-old woman with radiation-induced breast angiosarcoma (RIAS) in whom radical surgery with negative margins determined that at 14-month of follow-up there is no evidence of either local or systemic recurrence without having to resort to adjuvant chemotherapy.

Temporary Knockdown of p53 During Focal Limb Irradiation Increases the Development of Sarcomas

Approximately half of patients with cancer receive radiotherapy and, as cancer survivorship increases, the low rate of radiation-associated sarcomas is rising. Pharmacologic inhibition of p53 has been proposed as an approach to ameliorate acute injury of normal tissues from genotoxic therapies, but how this might impact the risk of therapy-induced cancer and normal tissue injuries remains unclear. We utilized mice that express a doxycycline (dox)-inducible p53 short hairpin RNA to reduce Trp53 expression temporarily during irradiation. Mice were placed on a dox diet 10 days prior to receiving 30 or 40 Gy hind limb irradiation in a single fraction and then returned to normal chow. Mice were examined weekly for sarcoma development and scored for radiation-induced normal tissue injuries. Radiation-induced sarcomas were subjected to RNA sequencing. Following single high-dose irradiation, 21% of animals with temporary p53 knockdown during irradiation developed a sarcoma in the radiation field compared with 2% of control animals. Following high-dose irradiation, p53 knockdown preserves muscle stem cells, and increases sarcoma development. Mice with severe acute radiation-induced injuries exhibit an increased risk of developing late persistent wounds, which were associated with sarcomagenesis. RNA sequencing revealed radiation-induced sarcomas upregulate genes related to translation, epithelial-mesenchymal transition (EMT), inflammation, and the cell cycle. Comparison of the transcriptomes of human and mouse sarcomas that arose in irradiated tissues revealed regulation of common gene programs, including elevated EMT pathway gene expression. These results suggest that blocking p53 during radiotherapy could minimize acute toxicity while exacerbating late effects including second cancers.

SIGNIFICANCE

Strategies to prevent or mitigate acute radiation toxicities include pharmacologic inhibition of p53 and other cell death pathways. Our data show that temporarily reducing p53 during irradiation increases late effects including sarcomagenesis.

Treatment and Outcomes of Radiation-Induced Soft Tissue Sarcomas of the Extremities and Trunk-A Systematic Review of the Literature

INTRODUCTION

Radiation-induced soft tissue sarcomas (RISs) are rare secondary malignancies with a dire prognosis. The literature on the management of these tumors remains scarce due to their low incidence. Our systematic review sought to assess the treatment alternatives and outcomes of patients with RIS.

METHODS

A systematic review was conducted following the PRISMA guidelines. Our study was registered in PROSPERO (ID: CRD42023438415). Quality assessment was performed using the STROBE checklist. Weighted means for both continuous and categorical values were calculated.

RESULTS

Twenty-one studies comprising 1371 patients with RIS were included. The mean latency period from radiation to RIS diagnosis was 14 years, and the mean radiation dose delivered to the primary malignancy was 29.2 Gy. The most common histological type was undifferentiated pleomorphic sarcoma (42.2%), and 64% of all tumors were high-grade. The trunk was the most common location (59%), followed by extremities (21%) and pelvis (11%). Surgery was performed in 68% of patients and, among those with an appendicular tumor, the majority (74%) underwent limb-salvage surgery. Negative margins were attained in 58% of patients. Chemotherapy and radiotherapy were administered in 29% and 15% of patients, respectively. The mean 5-year overall survival was 45%, and the local recurrence and metastasis rates were 39% and 27%, respectively.

CONCLUSIONS

In our study, the most common treatment was surgical resection, with RT and chemotherapy being administered in less than one third of patients. Patients with RIS exhibited poor oncologic outcomes. Future studies should compare RIS with de novo STS while controlling for confounders.

Radiation-associated secondary malignancies: a novel opportunity for applying immunotherapies

Radiation is commonly used as a treatment intended to cure or palliate cancer patients. Despite remarkable advances in the precision of radiotherapy delivery, even the most advanced forms inevitably expose some healthy tissues surrounding the target site to radiation. On rare occasions, this results in the development of radiation-associated secondary malignancies (RASM). RASM are typically high-grade and carry a poorer prognosis than their non-radiated counterparts. RASM are characterized by a high mutation burden, increased T cell infiltration, and a microenvironment that bears unique inflammatory signatures of prior radiation, including increased expression of various cytokines (e.g., TGF-β, TNF-α, IL4, and IL10). Interestingly, these cytokines have been shown to up-regulate the expression of PD-1 and/or PD-L1-an immune checkpoint receptor/ligand pair that is commonly targeted by immune checkpoint blocking immunotherapies. Here, we review the current understanding of the tumor-immune interactions in RASM, highlight the distinct clinical and molecular characteristics of RASM that may render them immunologically "hot," and propose a rationale for the formal testing of immune checkpoint blockade as a treatment approach for patients with RASM.

Clinico-demographic characteristics and outcomes of radiation-induced sarcomas (RIS): a CanSaRCC study

Background

Radiation-induced sarcomas (RIS) tend to have aggressive behaviour and because of their rarity, the most appropriate management for these malignancies is uncertain.

Objectives

Using the Canadian Sarcoma Research and Clinical Collaboration (CanSaRCC) database, a national sarcoma registry, we aimed to investigate prognostic factors and outcomes for RIS.

Design

Retrospective study of RIS patients treated from 1996 to 2021 at three Canadian centres.

Methods

RIS was defined as a sarcoma arising in a previously irradiated field following a 3+ year latency period, whose histology was distinct from the initially irradiated tumour. Clinicopathologic and treatment-related information was extracted from the CanSaRCC database. Overall survival (OS) was defined as the time from RIS diagnosis to death from any cause. Response rate (RR) to neoadjuvant chemotherapy (NACT) was based on physician assessment. Time-to-event analyses were estimated using the Kaplan-Meier method, with Cox regression for multivariate analysis. We considered a two-tailed p-value of <0.05 as statistically significant.

Results

One hundred seven tumours met the criteria for RIS and were divided into three subgroups: breast angiosarcoma (BAS, n = 54), osteosarcoma (OST, n = 16), and other soft-tissue sarcomas (STS, n = 37). Patients were mostly female (n = 85, 79%), treated initially for breast carcinomas (n = 54, 50.5%), and diagnosed with high-grade tumours (n = 61/71, 86%). None had evidence of synchronous metastasis. Patients with OST were younger (median age: 48 years, p < 0.001), and BAS had the shortest latency interval (8 versus 18 years for OST/STS, p < 0.001). Most patients underwent surgery, 76% (n = 76/100) R0; 24% (n = 26) received radiation therapy, mostly (n = 15, 57.7%) neoadjuvant. Among those receiving chemotherapy, 30 (75%) underwent NACT; among patients with documented response assessment, the RR was 68% (n = 17/25), being even higher in the BAS population (89.5%, n = 13/17). Median OS was 53 months (95% CI 34-101), with a 5-year OS of 47.6%; larger tumour size, high histologic grade and older age were independent prognostic factors for worse OS.

Conclusion

Surgery is standard, and NACT might be useful to downsize large lesions, especially in BAS patients. Raising RIS awareness is fundamental to promoting appropriate management and fostering research through multi-institutional collaborations.

'Radiation-induced pleomorphic sarcoma with rhabdomyoblastic differentiation of the lower limb following treatment of vaginal squamous cell carcinoma - A case report and review of the literature'

We present the case of a 59-year-old woman who developed a right thigh pleomorphic sarcoma with rhabdomyoblastic differentiation 6 years following radiotherapy for a vaginal squamous cell carcinoma. The overall 5-year survival for a gynaecological malignancy is more than 80 % and as overall cancer survivorship and life expectancy improves, the incidence of radiation-induced malignancy is increasing (Bjerkehagen et al., 2013). As the prognosis of those malignancies is usually poor, clinicians must have a high index of suspicion to try to detect these cases early.

Distinct genomic landscapes in radiation-associated angiosarcoma compared with other radiation-associated sarcoma histologies

MYC amplifications have been frequently detected in radiation (RT)-associated angiosarcomas (ASs) by low-resolution molecular methods. However, large-scale next-generation sequencing (NGS) studies to investigate the genomic landscape of RT-AS are scarce, particularly compared with other RT-associated sarcomas. We performed a detailed comparative genomic investigation of RT-AS versus other RT-associated histotypes, as well as sporadic sarcomas with similar histologies. Our institutional targeted DNA-NGS assay database was searched for RT-associated sarcomas. Clinical outcome data, pathologic diagnosis, and the types and frequencies of genomic alterations, including single nucleotide variants (SNVs) and copy number alterations (CNAs), were analyzed. The cohort consisted of 82 patients, 68 (83%) females and 14 (17%) males, aged 37-88 (mean 64) years. Forty-four RT-ASs (38 from breast) and 38 RT sarcomas of other histologies, including 12 malignant peripheral nerve sheath tumors (RT-MPNSTs), 14 undifferentiated pleomorphic sarcomas (RT-UPSs), and 12 osteosarcomas (RT-OSs), were included. Median time intervals from radiation to initial diagnosis in RT-AS (8.0 years) were significantly lower than those in RT-MPNST and RT-UPS (12.5 and 18.5 years), respectively. Each RT-sarcoma histotype harbored distinct mutations and CNAs. RT-associated AS had more frequent MYC, FLT4, CRKL, HRAS, and KMT2D alterations than sporadic AS (enriched in TP53, KDR, ATM, ATRX), whereas the mutational landscapes of MPNST, UPS, and OS were similar in both RT and non-RT settings. CDKN2A/B deletions and TP53 alterations were infrequent in RT-AS compared with other RT sarcomas. Among RT sarcomas, RT-AS harbored the lowest fraction of genome altered (FGA), while RT-MPNST showed the highest FGA. RT-AS had the lowest insertion:SNV and deletion:SNV ratios, while RT-UPS had the highest. The predominant mutational signatures were associated with errors in DNA repair and replication. In conclusion, RT-AS has a distinct genomic landscape compared with other RT sarcomas and sporadic AS. Potential molecular targets for precision medicine may be histotype-dependent. © 2023 The Pathological Society of Great Britain and Ireland.

Comparison of Clinical Outcomes, Pathologic Characteristics, and Immune-Related Features of Postradiation vs Sporadic Oral Cavity Squamous Cell Carcinoma

Importance

Postradiation oral cavity squamous cell carcinoma (OCSCC) is a common secondary malignant neoplasm affecting survivors of head and neck cancer who underwent radiotherapy. The clinical, pathologic, and immune-related features of postradiation OCSCC are poorly characterized, and treatment options are limited because of surgical difficulty and high morbidity associated with reirradiation.

Objective

To determine whether postradiation OCSCC has distinctive clinical, pathologic, and immune-related features compared with demographic-matched sporadic OCSCC.

Design, Setting, and Participants

This retrospective matched cohort study was conducted at a single tertiary oncology center in Hong Kong. Participants included consecutive patients with OCSCC diagnosed between 2000 and 2020. Patients with postradiation OCSCC were matched with patients with sporadic OCSCC using age, year of diagnosis, sex, and anatomic subsites. Data analysis was performed from July to December 2022.

Exposure

Head and neck irradiation involving the oral cavity before the diagnosis of OCSCC.

Main Outcomes and Measures

The primary outcomes were relapse pattern, survival, and causes of death. Pathologic features; immunohistochemical staining for programmed death-ligand 1, PD-1, MSH6, PMS2, FOXP3, and Ki67; and mRNA expression of 31 immune-related genes were also analyzed.

Results

A total of 173 patients, 60 with postradiation OCSCC (median [IQR] age, 63.8 [53.0-71.7] years; 43 men [71.7%]) and 113 with sporadic OCSCC (median [IQR] age, 64.4 [52.8-70.6] years; 83 men [73.5%]), were included. Patients with postradiation OCSCC had a higher proportion of N0 disease than those with sporadic OCSCC (50 patients [83.3%] vs 56 patients [49.6%]). With a median (IQR) follow-up of 10.2 (1.2-20.5) years, the 10-year relapse-free survival rates were lower in patients with postradiation OCSCC than sporadic OCSCC (29.6% [95% CI, 17.1%-43.2%] vs 52.4% [95% CI, 41.8%-62.0%]; P = .04), and the same was true for overall survival (30.5% [95% CI, 17.6%-44.4%] vs 52.3% [95% CI, 41.4%-62.1%]; P = .03). All relapses in patients with postradiation OCSCC were locoregional, whereas 35.2% of relapses (12 of 34 patients) in patients with sporadic OCSCC were distant. Despite similar 10-year disease-specific survival rates between the 2 groups (68.8% [95% CI, 55.8%-81.0%] vs 67.1% [95% CI, 57.5%-76.5%]; P = .91), patients with postradiation OCSCC had excess mortality due to pneumonia and cerebrovascular events. Postradiation OCSCC exhibited more adverse pathologic features (perineural invasion, worse pattern of invasion, and tumor budding), higher PD-1 expression, and higher gene expression of CD4 and TGF-β compared with sporadic OCSCC.

Conclusions and Relevance

This retrospective matched cohort study found distinctive pathologic characteristics and relapse patterns of postradiation OCSCC compared with sporadic OCSCC, which may be attributable to the lack of adjuvant radiotherapy, aggressive biologic phenotype, and different host immune response. Further exploration of the role of immune checkpoint therapy may be justified.

Pelvic soft tissue sarcomas

Pelvic soft tissue sarcomas (PSTS) are a rare, heterogeneous group of tumors. They have been usually analyzed with retroperitoneal sarcomas (RPS), but actually have key differences. Due to their unique anatomic location, symptomatic presentation of PSTS may be more common than RPS. Adequate imaging approach is paramount for guiding differential diagnosis, while preoperative biopsy is mandatory, especially when preoperative treatment may be considered as initial approach. The most frequent histologic subtype is leiomyosarcoma, which is different as expected in the retroperitoneum where liposarcoma is the commonest histology. Also solitary fibrous tumor is commonly diagnosed in the pelvis. Surgical approach for PSTS differs from that for RPS mainly due to anatomic relations. Similarly, in the lack of definite evidence from specific trials about neoadjuvant and adjuvant treatments, the anatomic constraints to obtain wide margins in the pelvis as well as the expected functional outcome in case of organ resections should be factored into decision for individualized treatment offer. Vascular and genitourinary involvement are frequent, as well as herniation through pelvic foramina. For these reasons a multidisciplinary surgical team should always be considered. Early referral of these patients to high-volume centers is critical and may impact on survival, given that optimal initial resection is a major predictor of curative treatment. International consensus on PSTS treatment is advocated, similarly to the recent efforts realized for RPS.

Radiation-Induced Sarcomas of the Breast: A Review of a 20-Year Single-Center Experience

Background Radiation-induced sarcomas (RISs) are histologically proven sarcomas within or around a previously irradiated site, per Cahan's criteria. RIS incidence is higher in breast cancer compared to other solid cancers and the prognosis remains poor given limited treatment options. This study aimed to review 20-year experience with RISs at a large tertiary care center. Methodology Using our institutional cancer registry database, we included patients meeting Cahan's criteria diagnosed between 2000 and 2020. Patient demographics, oncologic treatment, and oncologic outcomes data were collected. Descriptive statistics were used to describe demographic data. Oncologic outcomes were assessed using the Kaplan-Meier method. Results A total of 19 patients were identified. The median age at RIS diagnosis was 72 years (range = 39-82 months), and the median latency period for the development of RIS was 112 months (range = 53-300 months). All patients underwent surgery, three patients received systemic therapy, and six patients received re-irradiation as salvage treatment. The median follow-up time was 31 months (range = 6-172 months) from the diagnosis of RIS. Overall, five patients had local recurrence, and one patient developed distant metastases. The median time to progression was seven months (range = 4-14 months). The progression-free survival (95% confidence interval (CI)) at two years was 56.1% (37.4-84.4%). At follow-up two years after the diagnosis of sarcoma, the overall survival (95% CI) was 88.9% (75.5-100%). Conclusions While breast RIS remains rare, when managed in a large tertiary care center, overall survival outcomes appear favorable. A significant proportion of patients recur locally after maximal treatment and require salvage therapy to improve outcomes. These patients should be managed in high-volume centers where multidisciplinary expertise is available.

Carbon-fiber-reinforced polyetheretherketone orthopedic implants in musculoskeletal and spinal tumors: imaging and clinical features

Carbon-fiber-reinforced polyetheretherketone (CFR-PEEK) orthopedic implants are gaining popularity in oncologic applications as they offer many potential advantages over traditional metallic implants. From an imaging perspective, this instrumentation allows for improved evaluation of adjacent anatomic structures during radiography, computed tomography (CT), and magnetic resonance imaging (MRI). This results in improved postoperative surveillance imaging quality as well as easier visualization of anatomy for potential image-guided percutaneous interventions (e.g., pain palliation injections, or ablative procedures for local disease control). CFR-PEEK devices are also advantageous in radiation oncology treatment due to their decreased imaging artifact during treatment planning imaging and decreased dose perturbation during radiotherapy delivery. As manufacturing processes for CFR-PEEK materials continue to evolve and improve, potential orthopedic applications in the spine and appendicular skeleton increase. An understanding of the unique properties of CFR-PEEK devices and their impact on imaging is valuable to radiologists delivering care to orthopedic oncology patients in both the diagnostic and interventional settings. This multidisciplinary review aims to provide a comprehensive insight into the radiologic, surgical, and radiation oncology impact of these innovative devices.

Radiation-induced sarcoma of head and neck: Clinical characteristics and molecular signatures

BACKGROUND

Radiation-induced sarcoma of the head and neck (RISHN) is a rare yet devastating potential complication of radiotherapy treatment. We aimed to evaluate the clinicopathological characteristics and molecular signatures of RISHN in patients who underwent radiotherapy for head and neck cancer (HNC) to identify high-risk patients and enable earlier cancer detection.

METHODS

This study retrospectively evaluated 24 sarcoma patients who received radiotherapy for HNC between 1994 and 2019. Patients were divided into two groups based on RISHN latency period. Patient demographics, initial tumor staging, risk factors, and survival between groups were analyzed, and whole-exome sequencing (WES) of selected samples was performed.

RESULTS

The median age at diagnosis of RISHN was 54 years, and the male-to-female ratio was 2:1. The latency period ranged from 0.8 to 64.4 years (median 6.5 years), with a median survival of 21.5 months. Primary cancer in the oral cavity, treatment with alkylating agents, alcohol consumption, betel nut chewing, and smoking were identified as risk factors for short (<5 years) latency periods. The majority of RISHN cases occurred in the oral cavity (58.3%). WES analysis showed that tumor necrosis factor and cell cycle checkpoint pathways were differentially involved in both patient groups.

CONCLUSIONS

Although case numbers were small, our cohort represents the largest case series of RISHN from a single institution to date. Clinicians must be aware of factors affecting RISHN development and latency, and risk factor identification may lead to earlier detection and prevention in the future.

Experience of a single center in the treatment of rare malignant peripheral nerve sheath tumors during the years 1991-2021

Malignant peripheral nerve sheath tumor (MPNST) is a rare sarcoma with a poor prognosis, as the aggressive types of this cancer tend to grow rapidly and metastasize frequently. MPNST is associated with neurofibromatosis type 1 gene mutation. The minority of cases arise secondary to radiation therapy or sporadically. The primary treatment for MPNST is early surgical resection of the tumor. The aim of this study was to retrospectively evaluate the outcome of the treatment of MPNST in Helsinki University Hospital from the years 1991 to 2021. Fourteen MPNST cases were evaluated in this study retrospectively. Descriptive statistical analysis was performed on the collected patient data. Marginal resection was completed in nine cases, wide margins were achieved in three cases, and in two cases the final histological examination of the specimen revealed intralesional removal. During the follow-up time of 36.7 ± 12.1 months, all patients who underwent wide margin resection were alive. One patient died 22 months after intralesional resection and six within 38.3 ± 30.9 months of marginal resection. Seventy-one percent of tumor surgeries resulted in Clavien-Dindo class 3b complications, reflecting the complexity of the surgeries. The aggressive nature of MPNST and the large size of these tumors requires extensive surgery, which can lead to complications. The prognosis of MPNST needs improvement.

Post-irradiation sarcoma after definitive radiation therapy for nasopharyngeal carcinoma

BACKGROUND AND PURPOSE

Postirradiation sarcoma (PIS) is a rare radiation-induced malignancy after nasopharyngeal carcinoma (NPC) treatment.

MATERIALS AND METHODS

We retrospectively screened 9,185 NPC patients between 2000 and 2020 and identified 41 patients with PIS according to the modified Cahan's criteria: (1) the PIS must have arisen within a previous radiation field; (2) a latent period must have existed; (3) histologically proved sarcoma; (4) the tissue in which the PIS arose must have been healthy prior to the radiation. The initial radiation therapy techniques used were 2D (25; 61.0%), 3D (7; 17.1%), and IMRT (9; 22%).

RESULTS

The time (year) from radiotherapy (RT) to PIS was longer when using 2D or 3D irradiation techniques (median, 14.2; range, 3.4-28.1; Q1-Q3, 8.6-19.7) than when using IMRT (median, 6.6; range, 3.8-15.7; Q1-Q3, 4.5-11.7; P =.026). The time (year) from RT to PIS diagnosis was significantly longer when using lower radiation energy from cobalt-60 (median, 15.8; range, 10.4-28.4; Q1-Q3, 12.5-23.8) than when using a higher radiation energy of 6 or 10 MV (median, 10.2; range, 3.4-23.3; Q1-Q3, 6.5-16.1; P =.006). The 2-year overall survival rates for patients who underwent surgery, radical radiotherapy, systemic therapy alone and no treatment were 60.7 %, 42.9 %, 0 % and 0 %, respectively (P =.000). Of the 3 retrievable initial RT dosimetry plans for NPC, the D95 values (dose that covers 95 % of the PIS volume) for PIS were 6267, 6344 and 5820 cGy, respectively.

CONCLUSION

High radiation energy and modern techniques may shorten NPC PIS latency. Surgery may be associated with improved survival if feasible.

Genetic and environmental reprogramming of the sarcoma epigenome

Sarcomas are rare and heterogenous mesenchymal tumors occurring in soft tissue and bone. The World Health Organization Classification of sarcomas comprises more than hundred different entities which are very diverse in their molecular, genetic and epigenetic signatures as they are in their clinical presentations and behaviors. While sarcomas can be associated with an underlying hereditary cancer predisposition, most sarcomas developed sporadically without identifiable cause. Sarcoma oncogenesis involves complex interactions between genetic, epigenetic and environmental factors which are intimately related and intensively studied. Several molecular discoveries have been made over the last decades leading to the development of new therapeutic avenues. Sarcoma research continues its effort toward a more specific and personalized approach to all sarcoma sub-types to improve patient outcomes and this through world-wide collaboration. This chapter on "Genetic and Environmental Reprogramming of the Sarcoma Epigenome" provides a comprehensive review of general concepts and epidemiology of sarcoma as well as a detailed description of the genetic, molecular and epigenetic alterations seen in sarcomas, their therapeutic implications and ongoing research. This review also presents evidenced-based data on the environmental and occupational factors possibly involved in the etiology of sarcomas and a brief discussion on the role of the microbiome in sarcoma.

Practical Strategies in Reconstruction of Soft-Tissue Sarcoma

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Discuss the natural history and pathophysiology of sarcoma. 2. Summarize the most up-to-date multidisciplinary management of soft-tissue sarcoma. 3. Provide a synopsis of reconstructive modalities based on anatomical location. 4. Highlight some novel strategies for treatment of lymphedema and phantom limb pain that are common sequelae following treatment and resection of soft-tissue sarcomas.

SUMMARY

The management of soft-tissue sarcoma presents unique challenges to the reconstructive surgeon. The optimal management mandates a multidisciplinary approach; however, reconstruction must take into account the extent of the resection and exposed vital structures, but often occurs in the setting of adjuvant treatments including chemotherapy and radiation therapy. Reconstruction is based on the extent of the defect and the location of the primary tumor. As such, an evidence-based, algorithmic approach following the reconstructive ladder is warranted to minimize the risks of complications and maximize success, which varies from head and neck to torso to breast to extremity sarcomas. Aside from reconstruction of the defect, advances in the surgical treatment of lymphedema and neuropathic pain resulting from treatment and extirpation of soft-tissue sarcoma are critical to maintain function and patients' quality of life.

Treatment-related thoracic soft tissue sarcomas in US breast cancer survivors: a retrospective cohort study

BACKGROUND

Soft tissue sarcoma is a rare but serious side-effect of radiotherapy to treat breast cancer, and rates are increasing in the USA. We evaluated potential co-factors in two complimentary cohorts of US breast cancer survivors.

METHODS

In this retrospective cohort study, we sourced data from the Kaiser Permanente (KP) cohort and the Surveillance, Epidemiology, and End Results (SEER) 13 registries cohort, both in the USA. The KP cohort included 15 940 women diagnosed with breast cancer from Jan 1, 1990, to Dec 31, 2016, in KP Colorado, KP Northwest (which serves Oregon and Southwest Washington state), or KP Washington, with detailed treatment data and comorbidities (including hypertension and diabetes at or before breast cancer diagnosis) from electronic medical records. The SEER cohort included 457 300 women diagnosed with breast cancer from Jan 1, 1992, to Dec 31, 2016, within the 13 SEER registries across the USA, with initial treatment data (yes vs no or unknown). Eligibility criteria in both cohorts were female breast cancer survivors (stage I-III) aged 20-84 years at diagnosis who had breast cancer surgery, and had survived at least 1 year after breast cancer diagnosis. The outcome of interest was any second thoracic soft tissue sarcoma (angiosarcomas and other subtypes) that developed at least 1 year after breast cancer diagnosis. Risk factors for thoracic soft tissue sarcoma were assessed using multivariable Poisson regression models.

FINDINGS

In the KP cohort, median follow-up was 9·3 years (IQR 5·7-13·9) and 19 (0·1%) of 15 940 eligible, evaluable women developed a thoracic soft tissue sarcoma (11 angiosarcomas, eight other subtypes). Most (94·7%; 18 of 19) thoracic soft tissue sarcomas occurred in women treated with radiotherapy; thus, radiotherapy was associated with a significantly increased risk of developing a thoracic soft tissue sarcoma (relative risk [RR] 8·1 [95% CI 1·1-60·4]; p=0·0052), but there was no association with prescribed dose, fractionation, or boost. The RR of angiosarcoma after anthracyclines was 3·6 (95% CI 1·0-13·3; p=0·058). Alkylating agents were associated with an increased risk of developing other sarcomas (RR 7·7 [95% CI 1·2-150·8]; p=0·026). History of hypertension (RR 4·8 [95% CI 1·3-17·6]; p=0·017) and diabetes (5·3 [1·4-20·8]; p=0·036) were each associated with around a five-times increased risk of angiosarcoma. In the SEER cohort, 430 (0·1%) of 457 300 patients had subsequent thoracic soft tissue sarcomas (268 angiosarcomas and 162 other subtypes) after a median follow-up of 8·3 years (IQR 4·3-13·9). Most (77·9%; 335 of 430) cases occurred after radiotherapy; thus, radiotherapy was associated with a significantly increased risk of developing a thoracic soft tissue sarcoma (RR 3·0 [95% CI 2·4-3·8]; p<0·0001) and, for angiosarcomas, the RR for breast-conserving surgery plus radiotherapy versus mastectomy plus radiotherapy was 1·9 (1·1-3·3; p=0·012). By 10 years after radiotherapy, the cumulative incidence of thoracic soft tissue sarcoma was 0·21% (95% CI 0·12-0·34) in the KP cohort and 0·15% (95% CI 0·13-0·17) in SEER.

INTERPRETATION

Radiotherapy was the strongest risk factor for thoracic soft tissue sarcoma in both cohorts. This finding, along with the novel findings for diabetes and hypertension as potential risk factors for angiosarcomas, warrant further investigation as potential targets for prevention strategies and increased surveillance.

FUNDING

US National Cancer Institute and National Institutes of Health.

Histology-Specific Prognostication for Radiation-Associated Soft Tissue Sarcoma

PURPOSE

Radiation-associated sarcomas (RAS) are rare but aggressive malignancies. We sought to characterize the histology-specific presentation and behavior of soft tissue RAS to improve individualized prognostication.

METHODS

A single-institutional prospectively maintained database was queried for all patients with primary, nonmetastatic RAS treated with surgical resection from 1982 to 2019. Patients presenting with the five most common RAS histologies were propensity-matched to those with sporadic tumors of the same histology. Incidence of disease-specific death (DSD) was modeled using cumulative incidence analyses.

RESULTS

Among 259 patients with RAS, the five most common histologies were malignant peripheral nerve sheath tumor (MPNST; n = 19), myxofibrosarcoma (n = 20), leiomyosarcoma (n = 24), undifferentiated pleomorphic sarcoma (UPS; n = 55), and angiosarcoma (AS; n = 62). DSD varied significantly by histology (P = .002), with RAS MPNST and UPS having the highest DSD. In unadjusted analysis, RAS MPNST was associated with increased DSD compared with sporadic MPNST (75% v 38% 5-year DSD, P = .002), as was RAS UPS compared with sporadic UPS (49% v 28% 5-year DSD, P = .004). Unadjusted DSD was similar among patients with RAS AS, leiomyosarcoma, or myxofibrosarcoma and sporadic sarcoma of the same histology. After matching RAS to sporadic patients within each histology, DSD only differed between RAS and sporadic MPNST (83% v 46% 5-year DSD, P = .013). Patients with RAS AS presented in such a distinct manner to those with sporadic AS that a successful match was not possible.

CONCLUSION

The aggressive presentation of RAS is histology-specific, and DSD is driven by RAS MPNST and UPS histologies. Despite the aggressive presentation, standard prognostic factors can be used to estimate risk of DSD among most RAS. In MPNST, radiation association should be considered to independently associate with markedly higher risk of DSD.

Five decades of sarcoma care at Memorial Sloan Kettering Cancer Center

Early studies of the management of soft tissue sarcoma at Memorial Sloan Kettering Cancer Center were influenced by development of robust prospective long-term databases. Increasing capacity for molecular diagnostics has identified a myriad of subtypes with definable natural history. Accurate identification of tissue-specific risk of recurrence and disease-specific survival have increasingly allowed selective use of surgery, radiation therapy, and target-specific cytotoxic and immune therapies.

Clinical and Pathologic Characterization of 94 Radiation-Associated Sarcomas: Our Institutional Experience

Radiation-associated sarcomas are an uncommon complication of therapeutic radiation. However, their prevalence has increased with the more widespread use of this treatment modality. The clinical, pathologic and genetic characteristics of radiation-associated sarcomas are not fully understood. In this study we describe the features of 94 radiation-associated sarcomas reviewed at our institution between 1993 and 2018, evaluate their overall survival (OS) and progression-free survival (PFS) outcomes, and compare them with their sporadic counterparts reviewed within the same time period. Histologic subtypes of all radiation-associated sarcomas included 31 (33%) undifferentiated sarcomas, 20 (21%) osteosarcomas, 17 (18%) angiosarcomas, 10 (11%) malignant peripheral nerve sheath tumor (MPNST), 9 (10%) leiomyosarcomas, 4 (4%) myxofibrosarcomas, and 3 (3%) rhabdomyosarcomas. Six patients had a documented cancer predisposition syndrome. The most common preceding neoplasms included adenocarcinoma (47%) and squamous cell carcinoma (19%), with a mean latency of 13 years. Multivariable Cox survival analysis demonstrated that advanced stage at diagnosis based on pT category (AJCC eighth edition) and fragmented resection were associated with worse survival outcomes. In addition, there was a statistically significant difference in PFS between radiation-associated undifferentiated sarcomas and MPNST when compared to their sporadic counterparts using the Kaplan-Meier method and Log-rank analysis. Overall, our study shows that radiation-associated sarcomas comprise a wide clinico-pathologic spectrum of disease, with a tendency for aggressive clinical behavior. This study further delineates the understanding of these uncommon diseases. Future studies are necessary to better understand the genetic and epigenetic changes that drive the differences in behavior between these tumors and their sporadic counterparts, and to offer better treatment options.

Effects of Radiation Therapy and Chemotherapy on the Musculoskeletal System

The effects of radiation and chemotherapy on the musculoskeletal (MSK) system are diverse, and interpretation may be challenging. The different lines of treatment have effects on diseased and normal marrow, and they may lead to complications that must be differentiated from recurrence or progression. This review analyzes the changes induced by radiotherapy and chemotherapy in the MSK system in the adult and pediatric population, and the expected associated imaging findings. Treatments are often combined, so the effects may blend. Awareness of the spectrum of changes, complications, and their imaging appearances is paramount for the correct diagnosis. The assessment of body composition during and after treatment allows potential interventions to implement long-term outcomes and personalize treatments. Imaging techniques such as computed tomography or magnetic resonance imaging provide information on body composition that can be incorporated into clinical pathways. We also address future perspectives in posttreatment assessment.

Does Angiosarcoma of the Breast Need Nodal Staging?

BACKGROUND

Breast angiosarcoma is a rare malignancy classically associated with hematogenous metastases. We sought to determine the prevalence of pathologic nodal involvement in patients with nonmetastatic, resected breast angiosarcoma and its association with overall survival.

STUDY DESIGN

The National Cancer Database was used to identify patients with nonmetastatic angiosarcoma of the breast who underwent surgical resection from 2004 to 2017. The prevalence of regional lymph node operation and nodal positivity was calculated. The Kaplan-Meier method was used to evaluate overall survival among node-positive and node-negative patients. Cox proportional hazard modeling was used to evaluate the adjusted association of nodal positivity with overall survival.

RESULTS

We included 991 patients with angiosarcoma. The median age was 69 years (interquartile range 57 to 78), and the cohort was 99% female. A total of 298 patients (30%) had pathologic regional nodal evaluation. Of those, 15 (5.0%) had positive regional lymph nodes. Node-positive patients had significantly worse survival than patients with negative regional lymph nodes. After adjusting for patient, tumor, and treatment factors, a positive regional lymph node was associated with worse overall survival compared with patients with no nodal evaluation (hazard ratio 3.20; 95% CI 1.75 to 5.86; p < 0.001).

CONCLUSIONS

Patients with nonmetastatic angiosarcoma of the breast have a 5% regional lymph node positivity rate, which is at a common threshold to consider evaluation, and identifies patients with poor survival. A prospective study to determine performance characteristics of sentinel lymph node biopsy is warranted.

How Do the Outcomes of Radiation-Associated Pelvic and Sacral Bone Sarcomas Compare to Primary Osteosarcomas following Surgical Resection?

Radiation-associated sarcoma of the pelvis and/or sacrum (RASB) is a rare but challenging disease process associated with a poor prognosis. We hypothesized that patients with RASB would have worse surgical and oncologic outcomes than patients diagnosed with primary pelvic or sacral bone sarcomas. This was a retrospective, multi-institution, comparative analysis. We reviewed surgically treated patients from multiple tertiary care centers who were diagnosed with a localized RASB. We also identified a comparison group including all patients diagnosed with a primary localized pelvic or sacral osteosarcoma/spindle cell sarcoma of bone (POPS). There were 35 patients with localized RASB and 73 patients with POPS treated with surgical resection. Patients with RASB were older than those with POPS (57 years vs. 38 years, p < 0.001). Patients with RASB were less likely to receive chemotherapy (71% for RASB vs. 90% for POPS, p = 0.01). Seventeen percent of patients with RASB died in the perioperative period (within 90 days of surgery) as compared to 4% with POPS (p = 0.03). Five-year disease-specific survival (DSS) (31% vs. 54% p = 0.02) was worse for patients with RASB vs. POPS. There was no difference in 5-year local recurrence free survival (LRFS) or metastasis free survival (MFS). RASB and POPS present challenging disease processes with poor oncologic outcomes. Rates of perioperative mortality and 5-year DSS are worse for RASB when compared to POPS.

Clinical and Molecular Insights of Radiation-Induced Breast Sarcomas: Is There Hope on the Horizon for Effective Treatment of This Aggressive Disease?

Radiation-induced breast sarcomas (RIBS) are rare entities representing <1% of all primary breast malignancies, limiting most reports to small retrospective case series. They constitute a heterogeneous group of neoplasms, with high-grade angiosarcoma being the most common subtype. Other sarcoma histotypes, such as undifferentiated pleomorphic sarcoma and leiomyosarcoma, can also be identified. Radiation-induced breast angiosarcoma (RIBA) has an incidence of approximately 0.1% after breast-conserving therapy and arises mainly from the dermis of the irradiated breast. MYC gene amplification is highly indicative of secondary breast angiosarcomas. Their clinical presentation often mimics benign port-radiation lesions, leading to a delay in diagnosis and a lost window of opportunity for cure. Surgery with negative margins is the mainstay of treatment of localized RIBS. In the case of angiosarcoma, technical difficulties, including multifocality, infiltrative margins, and difficulty in assessing tumor margins, render surgical treatment quite challenging. A limited number of studies showed that adjuvant radiation therapy reduces local recurrences; therefore, it is proposed by many groups for large, high-grade tumors. Chemotherapy has been evaluated retrospectively in a small subset of patients, with some evidence supporting its use in angiosarcoma patients. Approximately half of patients with RIBA will show local recurrence. In the advanced setting, different therapeutic options are discussed in the review, including chemotherapy, antiangiogenic therapy, and immunotherapy, whereas the need for further research on molecular therapeutic targets is pointed out.

Application of additively manufactured 3D scaffolds for bone cancer treatment: a review

Bone cancer is a critical health problem on a global scale, and the associated huge clinical and economic burdens are still rising. Although many clinical approaches are currently used for bone cancer treatment, these methods usually affect the normal body functions and thus present significant limitations. Meanwhile, advanced materials and additive manufacturing have opened up promising avenues for the development of new strategies targeting both bone cancer treatment and post-treatment bone regeneration. This paper presents a comprehensive review of bone cancer and its current treatment methods, particularly focusing on a number of advanced strategies such as scaffolds based on advanced functional materials, drug-loaded scaffolds, and scaffolds for photothermal/magnetothermal therapy. Finally, the main research challenges and future perspectives are elaborated.

Radiation-induced osteosarcoma in the pubic bone after proton radiotherapy for prostate cancer: a case report

Objective: Radiation-induced sarcoma (RIS), which develops after radiotherapy, occurs as a secondary sarcoma in the irradiated area after a long latency period following radiation exposure.

Patient: A 59-year-old man underwent hormone therapy for prostate cancer, followed by proton therapy (74 GyE) four years ago. Positron emission tomography/computed tomography performed 2.5 years later revealed ¹⁸F-FDG accumulation in the left pubis. Three years after proton therapy, the patient developed gradually worsening left inguinal pain and visited our department. Imaging revealed bone destruction with a mixture of osteolysis and osteogenesis in the left pubis and the presence of an extraosseous tumor. Following biopsy, the patient was diagnosed with osteosarcoma.

Results: A systemic investigation revealed lung metastasis, and chemotherapy was initiated. The lung metastases shrank, and carbon ion radiotherapy (CIRT, 70.4 GyE) was performed on the left pubic lesion after colostomy. Six months after carbon ion radiotherapy, recurrence was observed in the irradiated field, and CIRT was performed again. However, the patient died 22 months after the initial diagnosis because of cancerous pleurisy and pericarditis.

Conclusions: Although RIS is rare, it should be actively identified using biopsy to confirm the diagnosis, keeping in mind that it is an important late complication of radiotherapy.

Fédération Nationale Des Centres de Lutte Contre Le Cancer (FNCLCC) Grading, Margin Status and Tumor Location Associate With Survival Outcomes in Malignant Peripheral Nerve Sheath Tumors

BACKGROUND

Histologic grading using the Fédération Nationale des Centres de Lutte Contre Le Cancer (FNCLCC) system is not universally accepted as applicable to malignant peripheral nerve sheath tumor (MPNST), as its prognostic value is not well established.

METHODS

We retrospectively evaluated 99 cases of MPNST to investigate any association between the outcomes overall survival (OS) and progression-free survival (PFS), and predictor variables FNCLCC grade, clinical setting, tumor location, and tumor size at diagnosis using multivariable Cox proportional hazard analysis.

RESULTS

Univariable and multivariable analysis demonstrate a statistically significant association between FNCLCC grade and both OS and PFS when comparing tumors by histologic grade. Of note, no deaths were observed in patients with grade 1 MPNST. Other variables associated with unfavorable outcomes include fragmented resection and primary site, with tumors in the extremities having favorable OS, but not PFS, when compared with those in truncal locations. Tumors in the head and neck had favorable PFS, but not OS, compared with those in the trunk. No statistically significant differences in OS or PFS were observed when comparing patient age and sex, tumor size at diagnosis, clinical setting (primary vs. type-1 neurofibromatosis vs. radiation associated) or history of neoadjuvant therapy. Interobserver agreement for FNCLCC grading of these tumors was considered good (S*=0.77, 95% confidence interval: 0.71-0.84).

CONCLUSIONS

Association between FNCLCC grading and survival outcomes in MPNST suggests potential value to routinely grading these neoplasms. However, the subjectivity of the grading system, particularly when assigning a tumor differentiation score, may pose a challenge, especially in low and intermediate grade lesions.

Rhabdomyosarcoma and pleomorphic sarcoma in the same location : Recurrence or new entity?

Soft tissue sarcomas (STS) represent a small group of adult solid malignancies, with risk factors such as environmental factors, genetic predisposition, and prior radiotherapy. In STS patients with a novel swelling, differential diagnoses include recurrence, second primary cancer, metastasis from unknown primary cancer, and radiation-associated STS, the latter usually occurring approximately 10 years after radiotherapy. We present the case of a 64-year-old male patient with pleomorphic rhabdomyosarcoma, who underwent resection and radiotherapy. The patient presented again 5 years later with painful swelling in the area of the prior sarcoma, raising suspicion of recurrence. Resection was performed and a diagnosis of pleomorphic sarcoma (not otherwise specified [NOS]) was made. The patient was treated with radiotherapy and remained sarcoma-free for the following 7 years. A molecular analysis of both neoplasms, using RNA next-generation sequencing, did not detect any specific fusions. Due to the lack of rhabdomyoblastic differentiation in the second sarcoma and the low likelihood of a second primary in the same previously irradiated location, the diagnosis of a radiation-associated STS was suggested. This short report illustrates the difficult diagnostic work-up of a presumably radiation-associated STS, as these neoplasms lack characteristic morphological and immunohistochemical features. In our case, the suggested diagnosis may have pointed against another course of radiotherapy in an already irradiation-harmed region. Therefore, a relatively low latency period between surgery, radiotherapy, and diagnosis of another STS should not automatically point towards recurrence and may prompt further in-depth investigation.