Radiation-Induced Sarcoma: A 15-Year Experience in a Single Large Tertiary Referral Center

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.

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 soft tissue sarcoma of the neck after radiation therapy for Hodgkin's lymphoma: a clinical case

Background. Radiation-induced malignancies are one of the long-term complications of radiation therapy, which is widely used to treat some tumors. The latency period before a second tumor develops varies from 3 to 60 years. Epithelial tumors and hemoblastoses occur after low-dose radiation therapy and sarcomas after high-dose radiation therapy. Aim. To present a case of radiation-induced soft tissue angiosarcoma of the neck after the cure of Hodgkin's disease. Materials and methods. A 41-year-old patient with Hodgkin's nodular lymphoma with the lymphoid predominance of stage IIIA with involvement of the right cervical and clavicular lymph nodes, mediastinum, and abdominal lymph nodes was followed-up. In 2004 the patient underwent four cycles of polychemotherapy per ABVD regimen followed by radiotherapy of the right cervical and clavicular lymph nodes and mediastinum, with a total focal dose of 40 Gy. Results. Seventeen years after the treatment for Hodgkin's disease, including radiation therapy, the patient presented with painful swelling of the neck soft tissues in the radiation area with the transition to the anterior thoracic wall and an enlarged cervical lymph node. A lymph node dissection was performed. According to the combined positron emission tomography and X-ray computed tomography (PET/CT), histological and immunohistochemical studies, epithelioid angiosarcoma of soft tissues of the neck and thoracic wall stage IV cT2N1M1G3 with metastases to the skeleton bones, neck lymph nodes, left adrenal gland was established. Surgical treatment was not performed due to advanced disease. The patient received six cycles of polychemotherapy with doxorubicin + ifosfamide. PET/CT confirmed partial tumor regression. Conclusion. Radiation-induced soft tissue sarcoma is a late iatrogenic complication of radiation therapy for Hodgkin's lymphoma. The tumor occurred in the radiation area. PET/CT is the method of choice in diagnosing and evaluating the extent of cancer and response to treatment. Chemotherapy, as an option for complex treatment, can achieve adequate disease control when surgery is not feasible.

Premalignant Conditions of Bone

Development of malignancy is a multifactorial process, and there are multitude of conditions of bone that may predispose patients to malignancy. Etiologies of malignancy include benign osseous conditions, genetic predisposition, and extrinsic conditions. New-onset pain or growth in a previously stable lesion is that should concern for malignant change and should prompt a diagnostic workup for malignancy.

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.

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.

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.

Pelvic Radiation-Induced Sarcoma With Rhabdomyoblastic Differentiation Following Treatment of Cervical Cancer

Radiation-induced sarcomas (RIS) are a rare long-term complication of radiation therapy, with a reported incidence of 2.5-5.5%. They usually develop several years following exposure to radiotherapy. The most common reported subtypes are undifferentiated pleomorphic sarcoma, angiosarcoma, and leiomyosarcoma. Breast cancer is the most common primary malignancy preceding RIS, followed by uterine cervical carcinoma. Only a few cases of RIS with rhabdomyoblastic differentiation have been reported in the literature, usually following the treatment of retinoblastoma. Herein, we report a rare case of RIS with rhabdomyoblastic differentiation in the pelvic region developing 12 years after cervical cancer radiation therapy.

Proliferating trichilemmal tumour of the eyelid in a 7-year-old girl

Proliferating trichilemmal tumours (PTTs) are rare cutaneous adnexal tumours derived from the hair shaft outer root sheath. We are reporting the first case of PTT in a young child. In this case, a 7-year-old girl presented with trichilemmal keratinisation consistent with PTT. The patient was monitored with no signs of recurrence. PTT is a rare tumour occurring primarily in adults and we present this case so that young patients with PTT can be diagnosed and treated appropriately with a painless, mobile, rapidly growing mass on the right upper eyelid. CT imaging showed well-circumscribed, heterogenous mass measuring 1.6 cm with fluid-filled appearance and no tissue invasion. Surgical excision was performed and pathology revealed an unencapsulated, well-demarcated tumour.

Incidence of radiation induced sarcoma attributable to radiotherapy in adults: A retrospective cohort study in the SEER cancer registries across 17 primary tumor sites

BACKGROUND

Previous studies have noted the incidence of radiation-induced sarcomas (RIS) but have not investigated the relative risk (RR) of developing RIS based on primary tumor organ disease site. By examining data from the Surveillance, Epidemiology, and End Results (SEER) database, we hypothesized that breast cancer would have a higher incidence of RIS compared to seventeen other primary cancer sites.

METHODS

This was a retrospective cohort study that examined patients from SEER registries between 1973 and 2013. We included patients aged 18 years or older who were diagnosed with cancer and those diagnosed with a cancer who subsequently developed a sarcoma. We excluded patients with missing information on initial radiotherapy treatment or stage. RIS was defined as those who developed a secondary sarcoma near the site of their original malignancy and after a 24-month latency period.

RESULTS

Our patients had a mean age of 60 years and follow up time of 9.2 years. Breast cancer comprised the majority with 693,701(36.8%) patients of which 161 (0.02%) had a secondary sarcoma. Of the 359 patients with secondary sarcomas, 242 (67.4%) had RIS. Breast cancer had the highest number of RIS patients at 126 compared to all combined non-breast cancer sites at 116. The RR of RIS in breast cancer versus 19 other primary cancer sites was 1.21 (CI: 1.01-1.45, p < 0.03, adjusted for age at primary diagnosis, gender, and latency).

CONCLUSIONS

Our study demonstrated that breast cancer has a higher risk of developing RIS compared to other solid cancers.

Radiation-Induced Sarcomas of the Head and Neck: A Systematic Review

Introduction

As a result of the increased use of radiotherapy (RT) and improved long-term overall survival of patients with cancers of the head and neck (HN), the frequency of radiation-induced sarcomas of the head and neck (RISHN) may be increasing. The main objective of this systematic review was to determine the existing evidence on the frequency, treatment, and outcome of RISHN.

Methods

Using PRISMA guidelines we conducted a systematic review of the literature published from 2000 to 2020.

Results

Our review includes data of 560 patients from 64 articles. The total frequency of RISHNs among the reviewed series was 0.15%. The most frequent location of the primary tumor treated by RT was the nasopharynx. The mean RT dose used was 62 Gy, mean latency interval between irradiation and occurrence of RISHN was 11.1 years, and the most common RISHN location was the sinonasal region. Osteosarcoma was the principal histology, followed by fibrosarcoma. Surgery was the most frequently applied treatment modality. Of all patients with RISHN, 40.7% died of this disease after a mean interval of 13.9 months.

Conclusions

Notwithstanding the increased use of RT, the number of reported RISHNs has not increased substantially during the past two decades. Surgery with wide margins forms the best therapeutic option for these cases, but the outcome remains poor.

Radiation-Induced Sarcoma: A Retrospective Population-Based Study Over 34 Years in a Single Institution

AIMS

About a half of all cancer patients receive radiotherapy as part of their oncological treatment. Because of the carcinogenic effect of ionising radiation, there is a rare, but definite, risk of developing secondary malignancies, including sarcomas. The aim of this retrospective study was to describe the prevalence, patient and tumour characteristics, as well as prognosis and outcome, of patients with radiation-induced sarcomas (RIS) in a cohort of patients treated in the Sarcoma Centre at Aarhus University Hospital over a period of 34 years.

MATERIALS AND METHODS

All patients who fulfilled the criteria for RIS and were treated for RIS in the period 1979-2013 were included. Patient data were retrieved from the Aarhus Sarcoma Registry and the National Danish Sarcoma Database, crosschecked with the National Register of Pathology and validated using the patients' medical records. The primary end point was the effect of surgery and treatment intent on overall survival. Overall survival is reported using the Kaplan-Meier estimates and compared using the Log-rank test. Descriptive statistics are presented for patients, tumours and treatment characteristics.

RESULTS

Of 2845 patients diagnosed with sarcoma between 1979 and 2013, 64 (2%) were diagnosed with RIS. The median interval from the original malignancy was 11 years. The most common histological type was undifferentiated pleomorphic sarcoma (33%). Curative treatment was intended for 45 patients. Fifty patients underwent surgery, of whom 80% had microscopically radical resection (R0). The 5-year overall survival for the whole cohort was 32%. Patients who underwent surgery had a significantly better overall survival compared with patients who were not treated with surgery. In the univariate Cox proportional hazard analyses, no metastases at diagnosis, surgery and R0 resection were favourable prognostics factors of survival.

CONCLUSION

This study showed that RIS patients are unique in their epidemiology and tumour characteristics. They have a poor prognosis and need special research investigating new intensive treatment strategies to improve the outcome.

Prognostic Score-Based Stratification Analysis Reveals Universal Benefits of Radiotherapy on Lowering the Risk of Ipsilateral Breast Event for Ductal Carcinoma In Situ Patients with Different Risk Levels

BACKGROUND

We aimed to analyze the effects of radiotherapy (RT) on the incidence rate of ipsilateral breast event (IBE) in ductal carcinoma in situ (DCIS) patients with lumpectomy after being stratified by prognostic score.

METHODS

We identified DCIS patients who received lumpectomy, from the Surveillance, Epidemiology, and End Results (SEER) database from 1988 to 2015. Cumulative incidence functions for competing risk were used to evaluate the effects of RT on IBE risk over time. Three multivariate regression models (weighted, non-weighted, and Fine-Gray) were applied to compare the IBE risk between the RT and non-RT groups after stratifying patients by prognostic score.

RESULTS

Overall, 72,623 DCIS patients were identified from the SEER database and 49,206 (66.8%) patients received RT. During the follow-up period (ranging from 7 to 347 months), the cumulative probability of invasive and in situ IBE was significantly lower in the RT group than in the non-RT group (p < 0.001). After being stratified by prognostic score, the weighted IBE incidence rate increased as the risk level increased (p < 0.050). In multivariate regression models, RT lowered the IBE incidence rate by at least 30% in low-, moderate-, and high-risk DCIS (p < 0.010). In particular, the in situ and invasive IBE incidence rate decreased by over 50% in low-risk DCIS with RT (p < 0.001).

CONCLUSIONS

RT is associated with a lowered IBE incidence rate in DCIS patients, regardless of the assigned risk levels for patients. The significant reduction in the IBE incidence rate in low-risk DCIS patients also indicates the potential benefits for recommending RT to such a patient population in clinical practice.

MYC expression has limited utility in the distinction of undifferentiated radiation-associated sarcomas from sporadic sarcomas and sarcomatoid carcinoma

AIMS

MYC is a proto-oncogene that is frequently dysregulated in various malignancies, through translocation or amplification. Radiation-associated angiosarcoma frequently shows MYC amplification, and immunohistochemical expression has been shown to be a reliable surrogate marker for amplification, but less is known about MYC expression in other sarcoma types, despite reports of MYC amplification in some undifferentiated/unclassified radiation-associated sarcomas (RASs). Distinguishing putative RAS from non-radiation-associated sarcoma or sarcomatoid carcinoma can be difficult. The aim of this study was to determine the prevalence and potential diagnostic utility of MYC in this context, by evaluating MYC expression in a cohort of RASs, non-radiation-associated sarcomas, and sarcomatoid carcinomas.

METHODS AND RESULTS

Three hundred and eighty-five neoplasms were evaluated, including 81 RASs (18 angiosarcomas; 57 undifferentiated sarcomas; three leiomyosarcomas; and three malignant peripheral nerve sheath tumours), 267 non-radiation-associated sarcomas, and 37 sarcomatoid carcinomas. Immunohistochemistry was performed with a monoclonal anti-MYC antibody. Staining in tumour cells was scored on the basis of extent (focal, 1-4%; multifocal, 5-49%; and diffuse, ≥50%) and intensity (strong, moderate, and weak). One hundred percent of radiation-associated angiosarcomas expressed MYC diffusely. Expression was infrequent among other types of RAS (9.5%), and the frequency was similar to that in non-radiation-associated sarcomas (9.7%). MYC expression was more common in sarcomatoid carcinomas, occurring in 43%. The extent and intensity of staining were variable in all groups.

CONCLUSION

MYC expression is infrequent among RASs other than angiosarcoma, and has a similar prevalence in sporadic sarcomas. Given the frequency of expression in sarcomatoid carcinomas, MYC expression outside the context of radiation-associated angiosarcoma is of limited diagnostic utility, and should be interpreted with caution after exclusion of sarcomatoid carcinoma where relevant.

Unique Case Report of a Meningeal Sarcoma Arising during Ongoing Treatment for Progressing Intraparenchymal Glioma

Radiation-induced sarcomas in the brain are extremely rare, usually occur with an average latency of 9 years, and are associated with poor outcomes. Latency periods shorter than 1 year may indicate a genetic predisposition such as Li-Fraumeni syndrome. A 34-year-old man underwent initial tumor resection and radiation therapy for a World Health Organization (WHO) Grade II Astrocytoma. Within 6 months, the tumor recurred as WHO Grade III and was treated with temozolomide and then bevacizumab. Despite the patient's apparent improving condition, MRI revealed new dural-based lesions 10 months after radiation therapy and identified as high-grade sarcoma. The patient resumed bevacizumab, began NovoTTF treatment for progressing glioma, and ifosfamide/doxorubicin for the sarcoma. Genetic testing revealed no pathogenic mutation in the TP53 gene. Ultimately, treatment was unsuccessful and the patient succumbed to glioma and sarcoma within 2 years of initial diagnosis. This case was unique due to the rapidly progressing glioma and sudden appearance of a high-grade sarcoma. It is unusual to have two separate intracranial primary cancers with each requiring a different chemotherapy regimen. We discuss the difficulty of simultaneously treating with separate chemotherapy regimens. It remains unclear whether the sarcoma was induced by the radiation treatment or a genetic predisposition.

Multifocal Superficial Rapidly Growing Postirradiation Sarcoma Mimicking Metastatic Carcinoma

Radiation induced sarcomas (RIS) on cytology is rare however need to be reported as they are histologically distinct from the primary tumor and arise years after completion of the radiotherapy. Fine needle aspiration cytology is mostly indicated in cancer patients suspected of recurrence/metastasis and rarely in secondary tumors post therapy or irradiation. Depending on the morphology and site of occurrence of RIS they can cause diagnostic difficulty with the primary carcinoma or sarcoma that was irradiated. Here we discuss a 49 yr old lady, known and treated case of carcinoma cervix who presented with multiple nodular swellings in the lower back and gluteal region and had clinical impression of metastatic carcinoma. The fine needle aspiration cytology smears revealed pleomorphic spindle shaped cells with abundant mitotic figures. Extensive immunocytochemical work up was done on the smear and cell block which helped to make a final conclusion of radiation induced pleomorphic sarcoma. The diagnosis of a tumor in a proven case of previous malignancy needs consideration of tumors secondary to therapy as well, along with the diagnostic differentials of metastasis or recurrence.

Radiation-induced sarcoma in a cat following hypofractionated, palliative intent radiation therapy for large-cell lymphoma

CASE SUMMARY

A 5-year-old female spayed domestic shorthair cat was presented with a 4.5 × 3 cm ulcerated cutaneous mass on the nasal bridge with extension into the nasal cavity. Tissue biopsy was obtained and a diagnosis of large-cell lymphoma was confirmed on histopathology. The cat was started on prednisolone and injectable chemotherapy; however, only a partial response was observed. A CT scan revealed a highly infiltrative mass with extensive subcutaneous involvement, extending into the nasal cavity, resulting in lysis of numerous nasal and facial bones. The cat received hypofractionated, palliative intent radiation therapy (four fractions of 8 Gray) and a complete clinical response was achieved. Nine months after radiation therapy, minimal residual intranasal disease was observed on advanced imaging. Sixty-nine months after the completion of radiotherapy, a mass was observed dorsal to the right eye within the previous radiation field. CT scan revealed a mass associated with the right frontal sinus with extension throughout the nasal cavity and facial bones. Histopathology was consistent with a moderately differentiated sarcoma. Seventy-one months post-radiation therapy, the cat developed neurologic clinical signs and was humanely euthanized. Radiation-induced sarcoma was suspected based on human criteria, which included history of irradiation and tumor development within the irradiated field, a latent period after irradiation prior to the development of the second tumor and histopathologic confirmation of a different malignant neoplasm at the irradiated site.

RELEVANCE AND NOVEL INFORMATION

To our knowledge, this is the first report of a malignant radiation-induced sarcoma in a cat. Based on this case, radiation-induced sarcomas should be considered as a late-term side effect associated with radiation therapy in cats.

Radiation-Associated Sarcomas: An Update on Clinical, Histologic, and Molecular Features

Approximately half of all cancer patients receive radiation therapy as part of their oncologic treatment. Radiation-associated sarcomas occur in fewer than 1% of patients who receive radiation therapy but account for up to 5% of all sarcomas. As the use of radiation has increased in the past few decades and overall oncologic outcomes are improving, the incidence of radiation-associated sarcomas is also expected to increase. Historically, radiation-associated sarcomas have been associated with poor outcomes but recent data suggest the prognosis is improving. Distinguishing the sarcoma from the primary malignancy is a major diagnostic criterion.

A Comparison of Outcomes and Prognostic Features for Radiation-Associated Angiosarcoma of the Breast and Other Radiation-Associated Sarcomas

PURPOSE

Radiation-associated sarcomas (RAS) are considered to have a poor prognosis. Although the incidence is anticipated to rise, contemporary data regarding predictors of outcomes are few. We performed a retrospective analysis to identify RAS prognostic factors and subset analyses for radiation-associated angiosarcoma arising after treatment for breast cancer (RAAB) and other RAS subtypes (other-RAS).

METHODS AND MATERIALS

Patients with localized RAS evaluated at an institutional multidisciplinary sarcoma clinic were identified. Clinical and histologic review was performed, and outcomes were assessed to identify prognostic features. A subset of cases underwent molecular analysis by next-generation sequencing.

RESULTS

Among 176 patients, histologic subtypes of RAS included angiosarcoma (41%), undifferentiated/unclassified sarcoma (40%), leiomyosarcoma (8%), malignant peripheral nerve sheath tumor (6%), and osteosarcoma (2%). Sixty-seven patients (38%) had RAAB, and 109 (62%) had other-RAS. RAAB had significantly shorter latency from time of initial radiation compared with other-RAS (8 vs. 15 years; P < .001). Treatment approaches included surgery (91%), chemotherapy (44%), and radiation therapy (27%). Median follow-up was 3.2 years; 3-year overall survival (OS) was 74%. On multivariate analysis, positive margins (P < .0001), deep tumor location (intrathoracic/intra-abdominal, P = .002), and high grade (P < .0001) were associated with worse OS. In particular, 3-year OS with negative versus positive margins was 90% versus 66%. Patients with RAAB versus other-RAS showed a trend for higher 3-year OS (84% vs 68%; P = .09), significantly higher 3-year metastasis-free survival (82% vs 67%; P = .001), but similar 3-year local recurrence-free survival (54% vs 61%; P = .28). Next-generation sequencing identified overall low tumor mutational burden, recurrent MYC amplification in RAAB, and few clinically actionable mutations.

CONCLUSIONS

Margin negative excision, superficial tumor location, and low tumor grade are determinants of improved OS for RAS, suggesting that complete surgical excision, when possible, is an optimal component of treatment. RAAB is a clinicopathologically distinct type of RAS with shorter latency from initial RT, different recurrence patterns, and when aggressively managed has potentially better outcomes compared with other-RAS.

Osteosarcoma of the jaw - experience at the Medical University Vienna and comparative study with international tumor registries

OBJECTIVES

Osteosarcoma of the jaw (OSAJ) is fundamentally different in clinical practice from its peripheral counterparts. Studies are difficult to conduct due to low incidence rates. The primary aim of this study was to provide for the first time a comprehensive retrospective analysis of the treatment concepts and outcome data of OSAJ patients treated at the University Hospital Vienna and to compare these with two recently published studies on OSAJ. The clinical study was accompanied by a biomarker study investigating the prognostic relevance of melanoma-associated antigen-A (MAGE-A) in OSAJ specimens.

METHOD

Eighteen patients were included, and their outcomes were compared to published data. Immunohistochemistry was performed with mouse monoclonal antibodies against MAGE-A. Survival rates were estimated by the Kaplan-Meyer method. The log-rank test was used to analyze potential prognostic parameters. Fisher's exact test was performed to define the significant differences between the survival rates of the current study and the DOESAK registry.

RESULTS

Disease-specific survival was 93.8% after five and 56.3% after ten years. The development of metastases (p=0.033) or relapse (p=0.037) was associated with worsened outcomes in our group as well as in the comparative group. Despite the different treatment concepts of the study groups, survival rates were comparable. MAGE-A failed to show prognostic relevance for OSAJ patients.

CONCLUSIONS

Uncertainties about the optimal treatment strategies of OSAJ patients will currently remain. Thus, prospective studies of OSAJ are needed but are only feasible in a multicenter study setting, conducted over a prolonged time period.

Radiation-Associated Sarcoma of the Neck: Case Series and Systematic Review

INTRODUCTION

Radiation-associated soft tissue sarcomas of the neck (RASN) constitute a rare and aggressive tumor type.

METHODS

A retrospective chart review at the authors' institution revealed 3 patients with RASN. A systematic review of the literature was also conducted using MEDLINE, Ovid, the Cochrane Library, and Embase.

RESULTS

Patients within the authors' institutional chart review presented from 6 to 26 years after neck radiation with neck masses. All patients underwent surgical resection with clear margins, and adjuvant radiation was offered when feasible. Patients had no evidence of disease at most recent follow-up. A total of 867 articles were screened for systematic review, revealing 9 articles detailing outcomes of RASN. Studies were small and heterogeneous, precluding pooled data. The importance of complete surgical extirpation was noted.

CONCLUSIONS

Complete surgical resection appears to be the mainstay of therapy, but there are limited data on management and outcomes of patients with RASN.

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

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

Case Report: Primary De Novo Sarcoma In Transplant Pancreas Allograft

BACKGROUND

The majority of malignancies after transplantation appear to be virally mediated and of recipient origin. Donor-derived neoplasms occur early, whereas recipient-origin tumors typically occur many years after transplantation. Sarcomas are a relatively rare form of cancer. The etiology of sarcomas remains largely unknown, although some are linked to viruses, familial cancer syndromes, or therapeutic radiation exposure. Primary sarcomas are extremely rare, accounting for <0.1% of all native pancreatic malignancies. The involvement of the allograft itself in the tumor is rare.

CASE REPORT

A 53-year-old white woman (body mass index, 20.1 kg/m²) with a history of type 1 diabetes, chronic kidney disease, coronary artery disease, dyslipidemia, and pancreas-alone transplantation in 2007 was admitted with small bowel obstruction secondary to a mass in the head of the pancreas allograft, for which a laparotomy with allograft pancreatectomy was required. Histopathologic exam revealed a stage III high-grade unclassified spindle cell sarcoma positive for polyomavirus. After surgery, the patient was managed with close monitoring for disease recurrence. Her most recent scan was negative for recurrence at postoperative day 489.

CONCLUSIONS

We report a previously unreported phenomenon of a soft tissue sarcoma arising in a pancreas allograft, likely of recipient origin and polyomavirus related. Standard treatment for sarcoma is wide excision of the tumor and close monitoring for recurrence. Systemic chemotherapy or radiotherapy is usually limited to advanced cases. Sarcomas may occur in a pancreas allograft. Allograft pancreatectomy and monitoring for recurrence is vital for a good outcome.

Radiation-associated neoplasia: clinical, pathological and genomic correlates

Ionizing radiation is an established risk factor for the development of benign and malignant tumours. The epidemiology of radiation-associated neoplasia has been studied over the decades in diverse populations, including Japanese atomic bomb survivors, exposed communities following the Chernobyl nuclear power plant disaster, and paediatric and adult populations receiving therapeutic irradiation. Radiation has been associated with an increased risk of neoplasia throughout the human body, with some sites showing a markedly increased relative risk of developing tumours (thyroid; soft tissues), depending on patient age and the context of exposure. Although the mechanisms of cellular injury and repair resulting from ionizing radiation are well described, the genomics of radiation-induced tumours are still relatively poorly understood, with some exceptions, such as RET rearrangement in thyroid carcinomas following iodine-131 exposure and MYC amplification in cutaneous angiosarcoma following chest wall irradiation for breast cancer. This review will provide a general overview of the epidemiology, molecular mechanism, pathology and genomics of radiation-associated neoplasia in humans.

Radiation-induced osteosarcoma of the maxilla and mandible after radiotherapy for nasopharyngeal carcinoma

Background

The increasing incidence of radiation-induced osteosarcoma of the maxilla and mandible (RIOSM) has become a significant problem that can limit long-term survival. The purpose of this study was to analyze the association of clinicopathologic characteristics with treatment outcomes and prognostic factors of patients who developed RIOSM after undergoing radiotherapy for nasopharyngeal carcinoma (NPC).

Methods

We reviewed the medical records of 53,760 NPC patients admitted to Sun Yat-sen University Cancer Center during the period August 1964 to August 2012. Of these patients, 47 who developed RISOM and met inclusion criteria were included in this study. Two of these 47 patients refused treatment and were then excluded.

Results

For all patients treated for NPC at Sun Yat-sen University Cancer Center during the study period, the total incidence of RIOSM after radiotherapy was 0.084% (47/53,760). Two patients (4.4%) had metastases at the diagnosis of RIOSM. Thirty-nine of the 45 (86.7%) patients underwent surgery for RIOSM; most patients (24/39; 61.5%) who underwent resection had gross clear margins, with 15 patients (38.5%) having either a gross or microscopic positive margin. All patients died. The 1-, 2-, and 3-year overall survival (OS) rates for the entire cohort of 45 patients were 53.3%, 35.6% and 13.5%, respectively. The independent prognostic factors associated with high OS rate were tumor size and treatment type.

Conclusions

RISOM after radiotherapy for NPC is aggressive and often eludes early detection and timely intervention. Surgery combined with postoperative chemotherapy might be an effective treatment to improve patient survival.