Intensive systemic chemotherapy in localized Ewing's sarcoma in childhood. A historical trial

Comparative characteristics of small cell lung cancer and Ewing's sarcoma: a narrative review

Background and Objective

Small cell lung cancer (SCLC) and Ewing's sarcoma (ES) at the disseminated stage are not amenable to therapy and have a dismal prognosis with low survival rates. Despite representing different tumor entities, treatment for both malignancies relies on cytotoxic chemotherapy that has not considerably changed for the past decades. The genomic background has been extensively studied and found to comprise inactivation of p53 and RB1 in case of SCLC and EWSR1/FLI1 rearrangement in case of ES resulting in aggressive tumors in adults with heavy tobacco consumption and as bone tumor in juveniles, respectively. New therapeutic modalities are urgently needed to improve the outcomes of both tumor entities, especially in patients with metastatic disease or recurrences. This review summarizes the common cell biologic and clinical characteristics of difficult-to-treat SCLC and ES and discusses their refractoriness and options to improve the therapeutic efficacy.

Methods

PubMed and Euro PMC were searched from January 1^st, 2012 to January 16^th, 2022 using the following key words: "SCLC", "Ewing´s sarcoma", "Genomics" and "Chemoresistance" as well as own work.

Key Content and Findings

Therapy of SCLC and ES involves the use of undirected cytotoxic drugs in multimodal chemotherapy and administration of topotecan for 2^nd line SCLC regimens. Despite highly aggressive chemotherapies, outcomes are dismal for patients with disseminated tumors. A host of unrelated drugs and targeted therapeutics have failed to result in progress for the patients and the underlying mechanisms of chemoresistance are still not clear. Identification of chemoresistance-reversing modulators in vitro and patient-derived xenografts of SCLC and ES has not translated into new therapies.

Conclusions

The global chemoresistance of SCLC and ES may be explained by physiological resistance at the tumor level and formation of larger spheroids that contain quiescent and hypoxic tumor cells in regions that occlude therapeutics. This type of chemoresistance is difficult to overcome and prevent the accumulation of effective drug concentration at the tumor cell level to a significant degree leaving therapeutic interventions of any kind ineffective.

Ewing Sarcoma-Diagnosis, Treatment, Clinical Challenges and Future Perspectives

Ewing sarcoma, a highly aggressive bone and soft-tissue cancer, is considered a prime example of the paradigms of a translocation-positive sarcoma: a genetically rather simple disease with a specific and neomorphic-potential therapeutic target, whose oncogenic role was irrefutably defined decades ago. This is a disease that by definition has micrometastatic disease at diagnosis and a dismal prognosis for patients with macrometastatic or recurrent disease. International collaborations have defined the current standard of care in prospective studies, delivering multiple cycles of systemic therapy combined with local treatment; both are associated with significant morbidity that may result in strong psychological and physical burden for survivors. Nevertheless, the combination of non-directed chemotherapeutics and ever-evolving local modalities nowadays achieve a realistic chance of cure for the majority of patients with Ewing sarcoma. In this review, we focus on the current standard of diagnosis and treatment while attempting to answer some of the most pressing questions in clinical practice. In addition, this review provides scientific answers to clinical phenomena and occasionally defines the resulting translational studies needed to overcome the hurdle of treatment-associated morbidities and, most importantly, non-survival.

Primary osseous tumors of the pediatric spinal column: review of pathology and surgical decision making

Spinal column tumors are rare in children and young adults, accounting for only 1% of all spine and spinal cord tumors combined. They often present diagnostic and therapeutic challenges. In this article, the authors review the current management of primary osseous tumors of the pediatric spinal column and highlight diagnosis, management, and surgical decision making.

Craniovertebral junction neoplasms in the pediatric population

INTRODUCTION

The incidence of tumors at the craniovertebral junction in the pediatric population is low. Because of the variable pathology and the rarity of these tumors, ideal therapies are only now being defined.

MATERIALS AND METHODS

Thirty-eight children with tumors affecting the craniocervical junction were encountered between 1991 and 2006. These comprised neoplasms of osseous origin and neural extramedullary tumors.

RESULTS AND DISCUSSION

Chordomas of the clivus and foramen magnum were seen in eight, fibrous dysplasia in four, aneurysmal bone cysts in four, eosinophilic granuloma affecting the atlas and axis vertebra in four, Ewing's sarcoma involving the atlas in two, osteoblastoma in two, neurenteric cysts in four, meningioma in five, schwannoma in two, and plexiform neurofibromas in three. The location of these tumors was predominantly ventral, and a very small number had a lateral or dorsal location. The ventral tumors included chordoma, meningioma, fibrous dysplasia, aneurysmal bone cyst, and osteoblastoma. Plexiform neurofibroma affecting the craniocervical junction was ventral to the clivus and upper cervical spine causing severe kyphosis of the craniocervical region. Pain in the head and neck occurred in 70%. Paresthesias and dysesthesias in the hands were seen in 40% and spastic weakness of extremities in 22%. Cranial nerve palsies were seen in 33%. Twenty-eight percent of children showed dysphagia or dysarthria. The cranial nerves affected were the vagus followed by hypoglossal and glossopharyngeal nerves. This led to dysphagia, slurred speech, repeated aspiration pneumonia, and weight loss. The most common findings for chordomas at the craniocervical junction were isolated hypoglossal nerve palsy. All individuals underwent magnetic resonance imaging, computed tomography, and 3D computed tomography and angiography. Vertebral angiography was used to understand the dynamics of collateral circulation and tumor vascularity. Tumor embolization was performed in chordoma and aneurysmal bone cysts. Our experience and results are presented here.

Multimodal therapy for children and adolescents with Ewing sarcoma: results of the First National Chilean Trial (1986-1991)

Thirty-seven patients with Ewing sarcoma were treated in the First National Chilean Trial for Ewing's Sarcoma (1986-1991), which comprised the St. Jude Ewing's 78 Study. All patients received cyclophosphamide, doxorubicin, vincristine, and Dactinomycin for a total treatment period of about 10 months, and all prescribed therapy was administered. Local therapy consisted of irradiation (RT) to the primary tumor, complete surgical resection, or a combination of both surgery and RT. Twenty-nine of these patients had localized tumors, 24% had pelvic primary tumors, 21 were males, and 20 were greater than 10 years of age at diagnosis. Twenty-one patients had tumors that were greater than 8 cm in largest diameter. Fourteen of the 29 patients with localized disease remain disease free at 23 to 91 months from diagnosis. Fourteen patients have died of-tumor-related complications and 1 of a secondary malignancy. Relapse was local only in 4, metastatic in 9, and local plus metastatic in 1. Only 1 of the 8 patients with metastatic disease at presentation remains disease free. Toxicity consisted primarily of myelosuppression and mucositis. We conclude that this form of relative intense multimodal therapy for children/adolescents with localized Ewing sarcoma is curative in about half of affected children as in the original St. Jude study, and that it can be safely given in a developing country, provided that careful attention to supportive care and treatment planning is given. Although these results represent improvement in outcome for our patients, more effective therapy is needed for children with Ewing sarcoma, especially those with metastatic disease at presentation.

Is neuro-ectodermal differentiation of Ewing's sarcoma of bone associated with an unfavourable prognosis?

Among Ewing's sarcoma (ES) of bone and related entities are tumours with neuro-ectodermal features that could represent a biologically distinct type. In order to assess the prognostic significance of the various forms of ES, a retrospective joint study involving three cancer centres in Europe and the U.S.A. was initiated. The material from 315 primary ES was reviewed by a panel of five pathologists and classified as typical ES (220 cases), atypical ES (48 cases) or ES with neuro-ectodermal features (47 cases). Prognostic factor analysis on treatment failure-free survival was performed using the Cox model. It included histopathological classification, initial patient characteristics, clinical presentation and treatment type. After multivariate analysis, in addition to treatment type (P < 0.001), metastases (P = 0.003) and proximal tumour location (P = 0.006), two histopathological parameters correlated with poor treatment failure-free survival, the presence of filigree pattern (P = 0.044) and dark cells (P = 0.043). We conclude that ES with neuro-ectodermal features does not appear to have a different outcome to the other subtypes.

Long-term outcome of patients with monostotic Ewing's sarcoma treated with combined modality

One hundred and twenty-one consecutive patients with monostotic Ewing's sarcoma (ES) were treated according to three consecutive combined modality programs from 1974 to 1986. Their 3-year progression free survival (PFS) rate from diagnosis of 59% was identical to the event free survival (EFS) rate, since all the 50 events occurring within 3 years from diagnosis were tumor recurrences. Primary tumor was treated with radiotherapy in 75 cases, surgical resection plus radiotherapy in 38, and radical surgery in 8. Chemotherapy was given to all patients and each program included adriamycin, vincristine, and cyclophosphamide +/- dactinomycin. Median follow-up was 12 years, ranging from 6 to 19 years. The PFS rate decreased to 49% at 6 years and plateaued at 46% after the 7th year from diagnosis, even though some relapses were observed as late as 14 years from diagnosis. Second malignancies developed in 7 patients free from progressive ES and were represented by osteogenic sarcoma in previously irradiated bone in 4 cases and by breast carcinoma in 3. No other event but tumor relapse or second malignancy occurred in this series. EFS rate was 47% at 6 years and 39% at 12 years, further decreasing in the following years because of a number of late events. A continuous PFS longer than 7 years may be consistent with cure in the majority of patients with monostotic ES. However, these patients should be followed indefinitely because of risk of second malignancies.

Does malignant small round cell tumor of the thoracopulmonary region (Askin tumor) constitute a clinicopathologic entity? An analysis of 30 cases with immunohistochemical and electron-microscopic support treated at the Institute Gustave Roussy

The morphology and clinical outcome of 30 patients with malignant small round cell tumors located in the thoracopulmonary region (Askin tumor) are reported. Histologically, all tumors had similar patterns, with small round-to-oval cells and a lobulated stroma. Immunohistochemical analysis always resulted in positive staining for one or several neural markers. No significant differences were found compared with the immunomarkers in 26 typical Ewing's sarcomas located outside the thoracic wall. In three specimens, electron microscopy confirmed the presence of membrane-bound neurosecretory granules. It was confirmed that there is a remarkable similarity among all malignant small round cell tumors, including Askin tumor and Ewing's sarcoma. Overall survival was poor with a 2-year rate of 38% and a 6-year rate of 14%.

Radiation therapy as local treatment in Ewing's sarcoma. Results of the Cooperative Ewing's Sarcoma Studies CESS 81 and CESS 86

The Cooperative Ewing's Sarcoma Studies, CESS 81 and CESS 86, are multiinstitutional trials with more than 80 participating institutions from Germany, the Netherlands, Austria, and Switzerland. Treatment consists of four courses of multiagent chemotherapy and local therapy. Local therapy was not randomized and was either radical surgery or resection plus postoperative irradiation or definitive radiation therapy. Here results according to local therapy have been analyzed for 93 protocol patients with localized Ewing's sarcoma (ES) who have been recruited in CESS 81 from January 1981 to February 1985 and 122 protocol patients recruited in CESS 86 from January 1986 to November 1989. The 3-year relapse-free survival (RFS) was 55% in CESS 81 and 62% in CESS 86. In CESS 81, the RFS was better for surgically treated than for irradiated patients. In this study there was an extremely high incidence of local failures (50%) after definitive irradiation. In CESS 86, however, the results after radiation therapy have been improved markedly (3-year RFS 67% after radiation therapy, 65% after surgery, and 62% after resection plus irradiation). Possible explanations for the improvement of radiotherapeutic results are as follows: selections for patients for radiation therapy, start of local therapy, and quality of radiation therapy. In CESS 86, irradiated patients were randomized to receive either conventionally fractionated irradiation with less intense chemotherapy or hyperfractionated irradiation with simultaneous chemotherapy. There was no difference in treatment results at the time of analysis. The authors conclude that selection of patients for local treatment modalities and quality of treatment performance has an impact on local and overall treatment results in ES.

Ewing's sarcoma in children: twenty-five years of experience at the Instituto Portugês de Oncologia de Francisco Gentil (I.P.O.F.G.)

Fifty children with Ewing's sarcoma were consecutively treated from 1962 to 1987 and retrospectively analyzed at the I.P.O.F.G. of Lisbon. At first diagnosis, 10 cases had distant metastases. The remaining 40 patients had clinically localized disease, and different protocols were followed over the years. The best results were obtained with chemotherapy and radiotherapy with or without surgery; and for these children the two-year survival rate was 42.8% vs. 8.3% for the group of patients submitted to local treatment alone. Besides the treatment modality, other factors influenced the prognosis, such as inflammatory signs, sex, tumor volume, and tumor site as well as evidence of distant metastases.

Prognosis of Ewing's sarcoma of the head and neck

Five children with Ewing's sarcoma, an uncommon neoplasm originating in the facial bones, were treated with chemotherapy, surgery, and radiotherapy. Younger children have poor prognoses. Children with tumors originating in the mandible appear to have better prognoses. Hematogenic metastases were the most frequent and those originating from maxillary tumors showed much faster growth and were resistant to the chemotherapy used.

Ewing's sarcoma of the mandible

Cure rates of Ewing's sarcoma have improved from 10% to 75% with the use of a combination of local therapy and aggressive multi-drug chemotherapy, to decrease both the incidence of local disease recurrence and the development of pulmonary and skeletal metastases. In Ewing's sarcoma of the mandible, complete surgical resection is preferred to irradiation for local control in those instances when surgery can be performed with minimal loss of function and disfigurement.

Local control and survival of Ewing's sarcoma in children with radiotherapy and chemotherapy without radical surgery

The present study was undertaken in 27 children with localized Ewing's sarcoma treated at our hospital. In 9 cases the lesion was central and in 18 peripheral. Treatment consisted of: 1) Chemotherapy with 6 drugs (vincristine, cyclophosphamide, methotrexate, bleomycin, dactinomycin and doxorubicin) for one year in all patients; 2) Radiotherapy in 24 patients at a dose of 30-40 Gy in the entire bone with a booster dose of 10-15 Gy in the lesion. In 7 patients debulking surgery was performed followed by irradiation. Two cases with tumor in expendable bones and one with extensive destructive lesion in the tibia underwent radical surgery. One patient suffered local recurrence (femur) and 6 developed distant metastases. The remaining 20 (74%) patients were alive and tumor-free after follow-up periods of 17-80 months. Among the 12 patients with extremity lesions who were alive, 7 (58%) had minimal or mild treatment sequelae, 2 moderate, and 3 severe sequelae but no amputation has been required. Our study shows that local control can be achieved in almost all patients without radical surgery and with acceptable extremity function in the majority.

Malignant peripheral neuroectodermal tumours of bone other than Askin's neoplasm: characterization of 14 new cases with immunohistochemistry and electron microscopy

Peripheral neuroectodermal tumours (PNET) of bone are rare and mimic those seen in soft tissue (peripheral neuroepithelioma of soft tissue). Their differential diagnosis from Ewing's sarcoma (Es) is extremely difficult by optical means. Here we report 14 new cases of PNET of bone (other than Askin's neoplasm) located primarily in the limbs, pelvic girdle and scapula. Clinically and radiologically they displayed Ewing's sarcoma-like features: mean age was 14.4 years, male/female ratio being 3:11. Metastasis was present in 6 cases at diagnosis (5 with bone metastasis). Prognosis was poor; thirteen patients died; only one with a metatarsal located tumour is alive and free of disease. The mean survival rate was 25 months following diagnosis and treatment with radio- and multimodal chemotherapy. Histologically the 14 cases displayed Homer-Wright rosettes and pseudorosette-like structures, as well as a fibrillary background and lobular pattern. Immunohistochemistry revealed positivity in a number of neural markers when using paraffin-embedded material: NSE, B-2-microglobuline, HNK-1 (leu-7) and E-36 antibodies. At EM level the cell cytoplasms evidenced dense-core granules with neurosecretion, neurotubules and intermediate filaments like those seen in peripheral neuroepithelioma.

Multidisciplinary treatment of primary Ewing's sarcoma of bone. A 6-year experience of a European Cooperative Trial

The German Society of Pediatric Oncology in 1981 initiated the Cooperative Ewing's Sarcoma Study (CESS 81) using a four-drug combination of chemotherapy prior to definitive local control with surgery and/or radiation. From January 1, 1981 until February 28, 1985, 93 patients were registered at the trial office from 54 participating institutions in West Germany, Austria, Switzerland, and the Netherlands. On February 1, 1987, 54 of 93 patients were disease-free. Using the Kaplan-Meier life table analysis, the estimated disease-free survival (DFS) rate was 60% at 36 months and 55% at 69 months. The median period of observation was 29 months, ranging from 22 months to 69 months. Twenty-one of 93 patients (23%) had local failure, 18 of 93 patients (19%) developed systemic metastases. The local failure rate was particularly high in patients treated with radiation and was reduced when radiation planning was centralized within the study based upon the extent of disease at diagnosis. Cox regression analysis of prognostic factors showed that tumor volume was a significant factor influencing prognosis. The estimated 3-year DFS rate was 80% for patients with small tumors (volume less than 100 ml) compared to 31% for patients with large tumors (volume greater than or equal to 100 ml). In patients who had surgery for local control, the histologic response to chemotherapy was analyzed on the surgical specimen and had a strong influence on survival: 79% DFS at 3 years for patients with less than 10% viable tumor (good responders) compared to 31% DFS for patients with more than 10% viable tumor (poor responders). Tumor load and responsiveness to chemotherapy are the two major factors influencing prognosis in patients with primary Ewing's sarcoma of bone.

Prognostic factors in the treatment of Ewing's sarcoma. The Ewing's Sarcoma Study Group of the German Society of Paediatric Oncology CESS 81

From 1981 up to February 1985, a total of 93 protocol patients entered the study CESS 81. The protocol recommended an initial 18-week period of polychemotherapy (VACA) followed by local therapy and two additional cycles of chemotherapy. Local therapy consisted either of radical surgery or of incomplete resection plus postoperative irradiation with 36 Gy or of radiotherapy alone (46 and 60 Gy). Centrally located lesions were always irradiated with 60 Gy. This article summarizes the data after 5 years. Data of 93 patients were analysed in October 1986 after a median follow-up of 37 months. The projected 5-year survival is 50%. The relapse rate was 42%, distant relapses occurred in 19%, local (plus distant) relapses in 23%. Most of the relapses occurred during the first 3 years of observation. Failure rate was high in patients undergoing irradiation alone (44%). Initial tumour mass (greater than 100 ml) and histopathologic response to initial chemotherapy were identified as major prognostic factors. Tumour site and type of local therapy were not significant if patients were categorised by tumour volume. In small lesions, surgery and radiotherapy were equally effective. In large lesions greater than 100 ml volume, a trend towards a better prognosis in surgically treated patients was observed. The results of CESS 81 emphasize the importance of permanent local control in Ewing's sarcoma even in the presence of systemic control by an effective multi-drug chemotherapy.

Prognostic significance of tumor volume in localized Ewing's sarcoma of bone in children and adolescents

A total of 60 consecutive patients with localized Ewing's sarcoma of bone who were entered into the Cooperative Ewing's Sarcoma Study of the German Society of Pediatric Oncology from January 1981 until April 1985 were evaluable for tumor volume at diagnosis. The tumor volume was calculated from plain X-rays and CT scans as ellipsoidal or cylindrical depending on the tumor configuration and presence or absence of a soft tissue component. The 3-year disease-free survival rate according to Kaplan-Meier life table analysis was 78% for tumors with a volume less than 100 ml compared to 17% for tumors greater than or equal to 100 ml volume. These results were independent of the site of the tumor, though larger tumors were primarily located in central and proximal extremity sites. Maximal tumor extension was less precise than tumor volume in predicting prognosis. The ratio of tumor volume to body surface area, body length, or body weight did not increase the ability to separate prognostic groups compared to tumor volume. The better prognosis for patients following radical surgery seems to be in part due to a biased distribution of tumor volumes within local therapy groups, since more patients with smaller tumors had surgery for local control.

Adjuvant chemotherapy in Ewing's sarcoma

Adjuvant chemotherapy using vincristine, cyclophosphamide, and adriamycin was used in 28 patients with localized Ewing's sarcoma. Life-table analysis revealed 55% disease-free survival at 3 years. In contrast, our historical control showed less than 10% long-term survival. Adjuvant chemotherapy appears to control both micrometastasis as well as local residual disease. The present study demonstrates the improved survival with adjuvant chemotherapy including adriamycin, vincristine, and cyclophosphamide, in patients with localized Ewing's sarcoma.

Histopathological predictive factors in Ewing's sarcoma of bone and clinicopathological correlations. A retrospective study of 261 cases

A retrospective multifactorial analysis on 261 previously untreated patients with Ewing's sarcoma (Es) of bone has been carried out in order to ascertain the prognostic value of several histological variables on survival. Among those cases accepted as Es, 208 (80% of the patients) were considered to be "typical Es", while 40 (15%) displayed a large cell predominance, being subclassified as "atypical large cell Es". Furthermore, 13 patients (5%) possessed tumours of endothelial-like appearance. Eleven cases which displayed a mixed histological configuration were finally included within one of the three previous groups according to their predominant histological pattern. After adjustment for therapeutic regimens and initial location of the tumour, only two histological characteristics remain significant; i.e. the presence of necrosis (p = 0.002) and, to a lesser degree, the presence of filagree "en damier" pattern (p = 0.08), both of which are of poor prognostic value. From this study, it can be assumed that the morphological (and possibly histogenetical) heterogeneity of Es of bone has no prognostic influence on survival.

Ewing's sarcoma: a trial of adjuvant chemotherapy and sequential half-body irradiation

The results of a pilot study using adjuvant chemotherapy and sequential half-body irradiation (HBI) for nonmetastatic Ewing's sarcoma are presented. Seventeen patients received Cyclophosphamide, Vincristine, and Adriamycin (8 cycles), followed by sequential radiation treatment of the upper (500 cGy) and lower (600 cGy) half body. Survival at 3 years was 49%. These results are contrasted with those for 18 concurrently treated patients who received standard adjuvant therapy. Overall 5-year survival and relapse-free survival for these 35 consecutive patients was 61 and 53%. The pilot protocol was given on an out-patient basis with limited and acceptable acute toxicology. Further study is necessary to determine the value of the pilot protocol.

Redefined role of radiation in combined treatment of Ewing's sarcoma

Eighty-six patients with Ewing's sarcoma were analyzed as to the role of radiation therapy. Fifty-eight patients (P group) had removal of the involved part of the bone after preoperative chemotherapy, and 28 (NP group) had local treatment either at the same time or before chemotherapy. Thirty-six of 58 P-group patients (61%) and 13 of the 28 NP-group patients (48%) are alive. Five of 48 patients in P-group, who had postoperative radiation, had local recurrence, as did 6 of 11 without postoperative radiation, a statistically significant difference (p = 0.001).

Local therapy of rhabdomyosarcoma, osteosarcoma and Ewing's sarcoma of children and adolescents

Local control of the primary tumour is a fundamental requirement for clinical cure. Towards this aim, the primary tumour must be diagnosed early and identified histologically. The size, extension, and spread within the patient must be defined precisely. In planning effective local therapy, additional questions must be answered including resectability, mutilation, sensitivity to radio- and chemotherapy, anticipated morbidity from therapeutic measures, etc. For osteosarcoma there is no reasonable alternative to radical surgery. Because of the 20% local recurrence rate of Ewing's sarcoma following radiotherapy, radical surgical removal of the primary tumour should be attempted whenever possible. For rhabdomyosarcoma, particularly for its embryonal histology, non-radical removal of the primary sarcoma is still compatible with a cure, provided adequate radio- and chemotherapy is also administered. Primary irradiation is indicated in radiosensitive unresectable primary tumours and may convert these into an operable state. Chemotherapy is the domain of prevention and treatment of metastatic disease. It has, however, also a proved effect on primary tumours and, in several recent protocols, precedes local therapy.