The Role of Next-Generation Sequencing in Sarcomas: Evolution From Light Microscope to Molecular Microscope

Purpose of Review

Sarcomas are rare, heterogeneous group of soft tissue and bone tumors. Precise diagnosis of specific subtypes is challenging using conventional methods. Herein, we review the role of next-generation sequencing (NGS) technology that is used for rapid sequencing of DNA and RNA.

Recent Findings

Recent sarcoma specific studies recommend that molecular genetic testing should be added at diagnosis for appropriate clinical management in addition to diagnosis by expert pathologists. NGS has already been used to identify potentially actionable mutations, copy number alterations, and gene fusions. Rationally, choosing a drug based on an individual patient profile aka: “precision oncology” has been so far limited to few case reports in sarcomas.

Summary

As we improve our ability to deliver personalized medicine using all modalities including conventional therapy, more patients may eventually benefit. As the cost and capacity of NGS outpace Moore’s law, so does the probability of success.

     

Metabolic iodine and tumours

Purpose

Purpose of the work is to highlight a possible connection between metabolic iodine and natural tumour control.

Method

Method adopted is to use information available in the literature.

Result

Result indicated a means of the purpose being attained.

Conclusion

Conclusion drawn is that a tumour control method derives from the relationship studied.

     

Descending thoracic aortic aneurysm revealing metastasis of a soft tissue fibrosarcoma: a case report and review of the literature

Background

Review of the first documented case of aortic wall metastasis from a limb sarcoma.

Case presentation

In a 56-year-old woman with a diagnosis of a high-grade limb fibrosarcoma, an aortic metastasis was revealed by a fast growing aneurysm of the descending thoracic aorta. This was managed with an endoprosthesis.

Conclusion

The presence of an aneurysm in a patient with a sarcoma with a high potential for metastasis and poor cardiovascular risk factors should alert physicians.

     

Clinical Characteristics and efficacy of chemotherapy in sclerosing epithelioid fibrosarcoma

Background

Sclerosing epithelioid fibrosarcoma (SEF) is a very rare soft tissue sarcoma subtype. Clinically it is an aggressive tumour; however, to our knowledge there are no published reports regarding the efficacy of chemotherapy in SEF. Therefore, the aim of this study was to document the outcome of a series of patients with SEF treated at a single referral centre with reference to systemic therapy.

Methods

A retrospective search of a prospectively maintained database was performed to identify all patients diagnosed with SEF between 1990 and 2017. The diagnosis was confirmed in each case by a dedicated soft tissue sarcoma pathologist. We analysed those with recurrent disease and the effect of systemic chemotherapy in the metastatic setting.

Results

Thirteen patients were identified, median overall survival from diagnosis and metastasis were 47.3 (95% CI 25.0–131.9) and 16.3 (95% CI 5.3–20.6) months, respectively. In total, 12 (92.3%) patients developed metastatic disease of which 10 died of disease, 1 was lost to follow-up and 1 had recently commenced palliative treatment. Among the 10 patients with metastatic disease, 7 received palliative chemotherapy. Palliative chemotherapy resulted in partial response in 1 patient, stable disease in 3 patients and progressive disease in 3 patients. Median time to disease progression was 2.7 (95% CI 1.2–4.4) months. Two of 13 patients were treated with adjuvant chemotherapy, receiving 6 cycles of liposomal doxorubicin and 1 cycle of doxorubicin, respectively, with a metastasis-free survival of 28.2 and 7.1 months, respectively.

Conclusion

SEF is an aggressive sarcoma subtype with a poor outcome and with limited responsiveness to conventional chemotherapy. Patients with this subtype should be considered for participation in clinical trials with novel agents. Further investigation into the biology of this rare disease is required to improve outcomes.

     

Characterizing the efficacy of cancer therapeutics in patient-derived xenograft models of metastatic breast cancer

Purpose

Basal-like breast cancers are aggressive and often metastasize to vital organs. Treatment is largely limited to chemotherapy. This study aims to characterize the efficacy of cancer therapeutics in vitro and in vivo within the primary tumor and metastatic setting, using patient-derived xenograft (PDX) models.

Methods

We employed two basal-like, triple-negative PDX models, WHIM2 and WHIM30. PDX cells, obtained from mammary tumors grown in mice, were treated with twelve cancer therapeutics to evaluate their cytotoxicity in vitro. Four of the effective drugs—carboplatin, cyclophosphamide, bortezomib, and dacarbazine—were tested in vivo for their efficacy in treating mammary tumors, and metastases generated by intracardiac injection of tumor cells.

Results

RNA sequencing showed that global gene expression of PDX cells grown in the mammary gland was similar to those tested in culture. In vitro, carboplatin was cytotoxic to WHIM30 but not WHIM2, whereas bortezomib, dacarbazine, and cyclophosphamide were cytotoxic to both lines. Yet, these drugs were ineffective in treating both primary and metastatic WHIM2 tumors in vivo. Carboplatin and cyclophosphamide were effective in treating WHIM30 mammary tumors and reducing metastatic burden in the brain, liver, and lungs. WHIM2 and WHIM30 metastases showed distinct patterns of cytokeratin and vimentin expression, regardless of treatment, suggesting that different tumor cell subpopulations may preferentially seed in different organs.

Conclusions

This study highlights the utility of PDX models for studying the efficacy of therapeutics in reducing metastatic burden in specific organs. The differential treatment responses between two PDX models of the same intrinsic subtype, in both the primary and metastatic setting, recapitulates the challenges faced in treating cancer patients and highlights the need for combination therapies and predictive biomarkers.

     

Looking for answers: the current status of neoadjuvant treatment in localized soft tissue sarcomas

Purpose

Sarcomas are a rare and heterogeneous variant of cancer. The standard of care treatment involves surgical resection with radiation in high-risk patients. Despite appropriate treatment approximately 50 % of patients will suffer and die from recurrent disease. The purpose of this article is to review the current evidence concerning the use of neoadjuvant chemotherapy with or without radiation in soft tissue sarcomas.

Methods

An in-depth literature search was conducted using Ovid Medline and PubMed.

Results

The most active chemotherapeutic agents in sarcoma are anthracyclines and ifosfamide. Adjuvant chemotherapy trials show only minimal benefit. Neoadjuvant chemotherapy offers the potential advantage of reducing the extent of surgery, increasing the limb salvage rate, early exposure of micrometastatic disease to chemotherapy, and assessment of tumor response to chemotherapy. Some retrospective and phase II trials suggest a benefit to neoadjuvant chemotherapy. Unfortunately, no clearly positive phase III prospectively randomized trials exist for neoadjuvant therapy in soft tissue sarcomas.

Conclusions

The current neoadjuvant chemotherapy trials that do exist are heterogeneous resulting in conflicting results. However, neoadjuvant chemotherapy with or without radiation can be considered in patients with high-risk disease in an attempt to improve long-term outcomes.

     

Preclinical Study of a Combination of Erlotinib and Bevacizumab in Early Stages of Unselected Non-Small Cell Lung Cancer Patient-Derived Xenografts

Background

The differential outcomes of clinical studies of the targeted therapies for non-small cell lung cancer (NSCLC) indicate that better stratification of patients is required. This could be achieved with the help of patient-derived xenografts (PDX) of epidermal growth factor receptor (EGFR) wild-type patients resistant to erlotinib treatment.

Objective

To explore the potential of patient-derived NSCLC xenografts to optimize therapy using 24 well-characterized early-stage NSCLC PDX.

Method

Patient tumor tissue was transplanted subcutaneously into nude mice. After engraftment, tumors were expanded and the sensitivity was tested. Gene expression analysis was used to identify differentially expressed genes between erlotinib responder (n?=?3) and non-responder (n?=?21). Tumor tissue was analyzed with TaqMan PCR, immunohistochemistry and ELISA to examine the response of the models.

Results

Gene expression analysis revealed vascular endothelial growth factor A (VEGFA) to be up-regulated in erlotinib non-responder. Because of that, the combination of erlotinib with bevacizumab was evaluated in one erlotinib-sensitive and four erlotinib-resistant PDX. Combination treatment was superior to monotherapy, leading to the highest and significant inhibition of tumor growth in all models investigated. A decline of VEGFA protein and an increase of VEGFA-mRNA were observed after bevacizumab treatment. Bevacizumab treatment resulted in a distinct decrease of blood vessel number.

Conclusion

This study showed that with the help of preclinical PDX models, drug combinations for therapy improvement can be identified on a rational basis. It was observed that a dual blockage of EGFR and VEGFA was more effective than a monotherapy for the treatment of NSCLC in selected PDX models. PDX could be employed to optimize the treatment of cancer patients.

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UAB30, a novel RXR agonist,decreases tumorigenesis and leptomeningeal disease in group 3 medulloblastoma patient-derived xenografts

Background

Group 3 tumors account for approximately 25–30% of medulloblastomas and have the worst prognosis. UAB30 is a novel synthetic rexinoid shown to have limited toxicities in humans and significant efficacy in the pediatric neuroectodermal tumor, neuroblastoma. We hypothesized that treatment with UAB30 would decrease tumorigenicity in medulloblastoma patient-derived xenografts (PDXs).

Methods

Three group 3 medulloblastoma PDXs (D341, D384 and D425) were utilized. Cell viability, proliferation, migration and invasion assays were performed after treatment with UAB30 or 13-cis-retinoic acid (RA). Cell cycle analysis was completed using flow cytometry. A flank model, a cerebellar model, and a model of leptomeningeal metastasis using human medulloblastoma PDX cells was used to assess the in vivo effects of UAB30 and RA.

Results

UAB30 treatment led to cell differentiation and decreased medulloblastoma PDX cell viability, proliferation, migration and invasion and G1 cell cycle arrest in all three PDXs similar to RA. UAB30 and RA treatment of mice bearing medulloblastoma PDX tumors resulted in a significant decrease in tumor growth and metastasis compared to vehicle treated animals.

Conclusions

UAB30 decreased viability, proliferation, and motility in group 3 medulloblastoma PDX cells and significantly decreased tumor growth in vivo in a fashion similar to RA, suggesting that further investigations into the potential therapeutic application of UAB30 for medulloblastoma are warranted.

     

Dendritic and mast cell involvement in the inflammatory response to primary malignant bone tumours

Background

A chronic inflammatory cell infiltrate is commonly seen in response to primary malignant tumours of bone. This is known to contain tumour-associated macrophages (TAMs) and lymphocytes; dendritic cells (DCs) and mast cells (MCs) have also been identified but whether these and other inflammatory cells are seen commonly in specific types of bone sarcoma is uncertain.

Methods

In this study we determined the nature of the inflammatory cell infiltrate in 56 primary bone sarcomas. Immunohistochemistry using monoclonal antibodies was employed to assess semiquantitatively CD45+ leukocyte infiltration and the extent of the DC, MC, TAM and T and B lymphocyte infiltrate.

Results

The extent of the inflammatory infiltrate in individual sarcomas was very variable. A moderate or heavy leukocyte infiltrate was more commonly seen in conventional high-grade osteosarcoma, undifferentiated pleomorphic sarcoma and giant cell tumour of bone (GCTB) than in Ewing sarcoma, chordoma and chondrosarcoma. CD14+/CD68+ TAMs and CD3+ T lymphocytes were the major components of the inflammatory cell response but (DC-SIGN/CD11c+) DCs were also commonly noted when there was a significant TAM and T lymphocyte infiltrate. MCs were identified mainly at the periphery of sarcomas, including the osteolytic tumour-bone interface.

Discussion

Our findings indicate that, although variable, some malignant bone tumours (e.g. osteosarcoma, GCTB) are more commonly associated with a pronounced inflammatory cell infiltrate than others (e.g. chondrosarcoma. Ewing sarcoma); the infiltrate is composed mainly of TAMs but includes a significant DC, T lymphocyte and MC infiltrate.

Conclusion

Tumours that contain a heavy inflammatory cell response, which includes DCs, TAMs and T lymphocytes, may be more amenable to immunomodulatory therapy. MCs are present mainly at the tumour edge and are likely to contribute to osteolysis and tumour invasion.

     

Pediatric Gynecologic Cancers

Purpose of Review

Three primary categories of gynecologic cancer are found in pediatric and adolescent patients: stromal carcinomas including juvenile granulosa cell tumors and Sertoli-Leydig cell tumors, rhabdomyosarcomas arising from the vagina and cervix (sarcoma botryoides), and ovarian germ cell tumors which comprise a wide range of histologies. These entities are rare and treatment approaches have focused on decreasing late effects of chemotherapy treatment. Here, we review presentation, histologic classifications, diagnosis, and treatment recommendations for pediatric gynecologic cancers.

Recent Findings

Event-free and overall survival for these cancers is high, and the goals of treatment are minimization of morbidity and preservation of fertility with unilateral salpingo-oophorectomies and limited staging. Surveillance of tumor markers after surgery is helpful in monitoring for disease progression and adjuvant chemotherapy is often reserved for patients at recurrence.

Summary

Recent literature supports avoiding chemotherapy even in high-grade germ cell tumors in the pediatric population.

     

Personalizing Maintenance Therapy in Metastatic Colorectal Cancer

Purpose of Review

Current systemic management of MCRC should include periods of intensive and less intensive treatment or even complete stop. Different systemic post-induction strategies have been evaluated in many trials. The aim of this article is to review the available data on maintenance strategies in MCRC and potential options to personalize choice of the respective strategy.

Recent Findings

Despite the large variability of clinical trials conducted in this setting, it can be concluded that intermittent chemotherapy does not seem to be inferior to continuous chemotherapy if at least 3 months of intensive induction treatment is applied, and active maintenance seem to be superior to complete stop after at least 3 months of induction treatment in terms of PFS and may add some benefit in terms of OS. The choice of the respective maintenance strategy may be personalized taking into account disease and patient characteristic, choice of induction treatment and response, treatment tolerability and quality of life.

Summary

Patients with metastatic colorectal cancer and no options of secondary resection or local ablation should be considered for a personalized maintenance approach.

     

Pneumothorax as adverse event in patients with lung metastases of soft tissue sarcoma treated with pazopanib: a single reference centre case series

Background

Recently, the phase III PALETTE study introduced pazopanib (Votrient®) as treatment for adult patients with locally advanced or metastatic non-liposarcoma soft tissue sarcoma after prior treatment with doxorubicin and/or ifosfamide. Pneumothorax was reported as adverse event in 8 of 246 treated patients (3.3%) in that study. This case series presents the incidence and clinic of this complication in the Leiden University Medical Centre.

Cases

Forty-three patients were treated with pazopanib of which six patients (14.0%) developed a pneumothorax. These six patients were treated for malignant peripheral nerve sheath tumour, angiosarcoma, synovial sarcoma, fibromyxomatoid sarcoma, pleomorphic sarcoma and endometrial stromal sarcoma. All six patients had subpleural pulmonary or pleural metastases at the start of pazopanib and the pneumothorax developed during or shortly after treatment with pazopanib and was difficult to treat.

Discussion

The incidence reported by us is higher than the incidence in the PALETTE study. Trials with pazopanib in renal cell carcinoma, urothelial carcinoma and cervix carcinoma did not report pneumothorax as an adverse event, suggesting pneumothorax as a specific adverse event in soft tissue sarcoma patients treated with pazopanib. This may be related to the fact that there is often pleural metastatic involvement and cystic degeneration due to pazopanib treatment may add to the risk.

Conclusion

The risk of an, often difficult to treat, pneumothorax during pazopanib therapy should be discussed with the patient before initiation of treatment for a pulmonary metastasized sarcoma and physicians should be alert to the occurrence of such an event.

     

Triple-Negative Breast Cancers: Systematic Review of the Literature on Molecular and Clinical Features with a Focus on Treatment with Innovative Drugs

Purpose of Review

Triple-negative breast cancer (TNBC) accounts for 15–20% of diagnosed breast tumours, with higher incidence in young and African-American women, and it is frequently associated with BRCA germline mutations. Chemotherapy is the only well-established therapeutic option in both early- and advanced-stages of the disease. TNBC tumours relapse earlier after standard anthracycline- and/or taxane-based chemotherapy treatments, generally within 1–3 years after the diagnosis, and often develop visceral metastases, representing the subtype with a worse prognosis among all breast cancers. In the present review, we will provide an updated overview of the available results of recent clinical trials for this disease and we will describe the implications of the known molecular pathways representing novel targets for development of future therapies for TNBC patients.

Recent Findings

Over the past decade, the advent of gene expression micro-array technology has led to the identification of different actionable targets including various genomic alterations, androgen receptor, PARP, PI3K, VEGF and other proteins of the angiogenic pathway. Thus, novel targeted drugs have been tested in clinical trials reporting promising results in specific TNBC molecular subgroups.

Summary

Although cytotoxic chemotherapy remains the mainstay of treatment for TNBC patients, the identification of novel ‘drugable’ targets and pathways for developing personalized treatments represents a promising investigational approach in the management of the TNBC subtype.

     

Resistance Mechanisms to Colorectal Cancer Therapeutics and the Clinical Implications

Purpose of Review

Colorectal cancer (CRC) is a leading cause of cancer-related death and additional treatment options are urgently needed. Cytotoxic chemotherapy has been the mainstay of treatment options for patients for many years, including FOLFOX (leucovorin, 5-fluorouracil (5-FU), and oxaliplatin) or FOLFIRI (5-FU, leucovorin, and irinotecan) Here we review the current clinical use of systemic therapies for metastatic CRC and mechanisms of resistance to these agents.

Recent Findings

Biologic therapies, including anti-angiogenic and anti-epidermal growth factor monoclonal antibodies, have shown increased efficacy for patients with metastatic CRC. Most recently, immunotherapies have also been an option for some patients.

Summary

Identification of molecular markers predictive of response or resistance has led to enhanced ability to treat patients with metastatic CRC in a more personalized fashion.

     

Les tumeurs endocrines rectocoliques: particularités anatomocliniques et thérapeutiques

Background

Endocrine tumours of the gastro-intestinal tract are rare and predominate in the small intestine and in the appendix, less commonly in the colon and the rectum.

Aim

The aim of this study is to analyze clinical and pathologic features of an endocrine tumour of the colon and the rectum diagnosed in the Department of Pathology (Sousse, Tunisia).

Methods

Five cases were diagnosed between 1992 and 2006 in our hospital unit. The medical records of the affected patients were analyzed. The pathological material was reviewed and the tumours were classified according to 2000 WHO classification.

Results

The study population consisted of 2 male and 3 female patients. Their median age was 55 years. Two poorly differentiated endocrine carcinomas of the colon, and one colic and two rectal well differentiated endocrine carcinoma were identified.

Conclusion

This study illustrates the importance of adequately diagnosing endocrine tumours because their treatment and prognosis are different from those of conventional carcinoma.

     

Tumeurs à cellules géantes de l’os. Particularités anatomocliniques: à propos de 14 cas

Introduction

Giant cell tumors of the bone have specific morphologic features and a progressive course pattern but they lack accurate prognostic criteria.

Patients and method

We report a retrospective study of fourteen cases of giant cell tumor of the bone diagnosed in the pathology department of the Farhat-Hached hospital, Sousse city, between 1990 and 2007. The radiological and histological images were reviewed and compared with the clinical and therapeutic data from the patients’ follow-up.

Results

Our results were as follows: five patients out of seven with grade I tumour had a local recurrence; one patient out of seven with a grade II tumour had a local recurrence with synchronous pulmonary metastases; eight patients had a favourable outcome without any recurrence or metastasis.

Conclusion

The histological parameters only may not predict the propensity for a giant cell tumor to induce recurrence or metastasis; the clinical, radiological and biological features must be always taken in consideration.

     

Nichtkleinzelliges Lungenkarzinom – Pathologie und Biologie

Background

Non-small cell lung cancer (NSCLC) accounts for ca. 75% of malignant epithelial neoplasms of the lungs. In recent years profound insight has been gained regarding the molecular mechanisms of lung carcinogenesis and subsequently new targeted therapies as well as immunotherapies have been developed. These advances have had a significant impact on routine diagnostics in pathology.

Objective

The article aims to give an overview of the most common histological subtypes of NSCLC as well as the morphological, immunohistochemical and molecular characteristics.

Material and methods

Selective search of the PubMed database.

Results and discussion

Adenocarcinomas, squamous cell carcinomas and large cell carcinomas are the most common histological subtypes. With the ancillary methods available in routine pathology even poorly differentiated tumors can be assigned to these entities. The NSCLC show numerous genetic changes of which alterations of EGFR, MET, ALK1 and ROS1 are target structures for personalized therapy.

     

Predictive factors for survival in neoadjuvant radiochemotherapy for advanced rectal cancer

Introduction

Neoadjuvant radiochemotherapy followed by radical surgery is the standard approach in advanced rectal carcinoma. Tumor response is determined in histological specimen.

Objective

To assess predictive factors for survival in 115 patients.

Patients and Method

115 patients treated with neoadjuvant radiochemotherapy followed by radical surgery with total mesorectal excision, in our hospital from January 2007 to December 2014. All patients received pelvic radiotherapy with concomitant chemotherapy, followed by radical surgery and in some adjuvant chemotherapy.

Results

In univariate analysis, distance to anal verge, radial margin, perineural invasion, and good grade regression are predictive factors for both, specific and disease free survival; and in multivariant, only radial margin and perineural invasion were predictive factors for survival. We found distance to anal verge (<5 cm) as the only clinical factor to predict a positive margin in the histologic specimen.

Conclusions

Perineural invasion and positive radial margin are predictive factors for both specific and disease free survival.

     

Cancers et environnement : explorer les comportements de recherche et les sources d’information des personnes atteintes et non atteintes d’un cancer

Aim

To explore information-seeking behaviors on links between cancers and environment.

Method

Focus groups and individual semi-structured interviews realized, respectively, with individuals without and with personal cancer experience.

Results

The majority of respondents reported informationscanning behaviors. Only half cancer patients searched for information regarding the links between cancers and environment.

Conclusion

Little information is sought on links between cancers and environment.