Unusual sites of extrapulmonary metastases of osteosarcoma after several lines of treatment

Metastatic osteosarcoma bowel perforation secondary to chemotherapy-induced tumour necrosis

Osteosarcoma is the most common paediatric and adolescent primary bone malignancy and is highly chemosensitive. Gastrointestinal metastases from osteosarcomas are rare. Bowel perforation secondary to chemotherapy is a potential serious complication reported in ovarian, colorectal and haematological malignancies. We report the first documented case of chemotherapy-mediated bowel perforation in an osteosarcoma patient with gastrointestinal metastases. A man in his 20s, with a history of resected osteosarcoma in remission, presented with abdominal pain. A computed tomography (CT) scan demonstrated a large calcified intrabdominal mass (15×13×9 cm) consistent with new peritoneal disease. After one cycle of palliative ifosfamide and etoposide chemotherapy, he developed a large bowel perforation and neutropenic sepsis consequently requiring resection of the perforated mass. Chemotherapy-induced bowel perforation is a rare but serious complication that should be considered in patients with osteosarcoma, and other chemosensitive malignancies, with intra-abdominal metastases. Recommencement of systemic therapies after bowel complications must be assessed cautiously on a case-by-case basis.

Synchronous lung and multiple soft tissue metastases developed from osteosarcoma of tibia: a rare case report and genetic profile analysis

Background

Osteosarcoma is the most common primary malignant bone tumor with a highly metastatic propensity in children and young adolescents. The majority of metastases develope in the lung, while metastases to the extrapulmonary locations have rarely been discussed, especially in skeletal muscle.

Case presentation

We reported a young patient with pathologically diagnosed osteosarcoma of the right tibia who was initially treated with standard chemotherapy and complete surgical resection. However, pulmonary metastases and multiple soft tissue masses in skeletal muscle developed four years after the index surgical resection. Subsequently, a targeted next-generation sequencing assay based on an 806 oncogenes and tumor suppressor genes panel was performed to analyze genetic alterations in this patient with rare metastatic pattern. The genetic analysis revealed canonical somatic mutations of RB1 and germline variants of ALK (c.862 T > C), BLM (c.1021C > T), PTCH1 (c.152_154del), MSH2 (c.14C > A), RAD51C (c.635G > A). Using silico prediction programs, the germline variants of the MSH2 and RAD51C were predicted as “Possibly Damaging” by Polymorphism Phenotyping v2 (PolyPhen-2) and “Tolerated” by Sorting Intolerant from Tolerant (SIFT); BLM was classified as “Tolerated”, while the germline variant of ALK was predicted to be pathogenic by both PolyPhen-2 and SIFT.

Conclusions

Osteosarcoma with extrapulmonary metastases is rare, especially located in the skeletal muscle, which predicts a worse clinical outcome compared with lung-only metastases. The several novel variants of ALK, BLM, PTCH1 in this patient might expand the mutational spectrums of the osteosarcoma. All the results may contribute to a better understanding of the clinical course and genetic characteristics of osteosarcoma patients with metastasis.

Metástase retroperitoneal, hepática e de linfonodo de osteossarcoma tibial proximal: Relato de caso

Homem adulto com osteossarcoma na tíbia proximal, tratado com cirurgia de salvamento de membro com endoprótese e quimioterapia. Ele desenvolveu um padrão metastático incomum, comprometendo fígado, ossos e linfonodos inguinais, sem recorrência local na tíbia nem metástases pulmonares. O osteossarcoma (OS) é o segundo tumor ósseo primário mais frequente, depois do mieloma múltiplo em adultos. Os locais frequentes das metástases, em caso de progressão da doença são os pulmões e os ossos. As metástases extrapulmonares são raras. O desenvolvimento de novos esquemas de quimioterapia melhorou a expectativa de vida dos pacientes com osteossarcoma, porém, alterou também os padrões usuais de metástases, resultando em localizações metastáticas incomuns.

Metastasis of Osteosarcoma to the Abdomen: A Report of Two Cases and a Review of the Literature

Two cases of primary distal femur osteosarcoma with subsequent metastasis to the abdomen are presented. In both cases, the development of abdominal metastasis was quickly followed by patient decline and death. A review of the literature was performed, assessing the presentation and survival of patients with osteosarcoma metastasized to the abdomen. As illustrated by the current cases and the literature review, abdominal metastasis in osteosarcoma is often a late manifestation and terminal prognostic indicator. Nonetheless, early detection and prompt intervention of this less common site of disease metastasis may improve patient care and palliative therapy.

Composite sarcoma of bone with focal rhabdomyosarcoma and lymph node metastasis in an adolescent

Composite sarcoma of bone is a very rare entity that primarily affects adolescent and young adult patients. It usually combines areas of liposarcoma and osteosarcoma, and up to 60% of cases have metastatic disease at diagnosis. It is a highly aggressive pathology with intrinsic resistance to bone sarcoma conventional treatments. The prognosis is poor, with long-term survival rates not exceeding 30%. We present the case of an adolescent female diagnosed with an aggressive composite sarcoma of bone with rhabdomyosarcoma foci and loco-regional lymph node involvement.

Sarcoma Surveillance: A Review of Current Evidence and Guidelines

After initial treatment of sarcoma, disease progression may occur in the form of local recurrence, pulmonary metastases, or extrapulmonary metastases. As such, surveillance is an important aspect of management, but no universally accepted practice standards are found. In the absence of strong evidence, and to allow for individualized care, existing guidelines contain flexibility in terms of both the frequency and modality of surveillance. In general, they agree that follow-up should be more intense in the early years after treatment, especially for high-grade sarcomas, and continue for at least 10 years. For local recurrence, data suggest that physical examination is usually sufficient for monitoring; in addition, some guidelines endorse imaging routinely, whereas others only as clinically indicated. For pulmonary metastasis, either radiograph or CT is recommended, with the latter having theoretical advantages but no proven survival benefit to date. Extrapulmonary metastases are rare in most sarcoma types, so the literature only supports extrapulmonary surveillance for certain diagnoses. This topic is complicated by the diversity of sarcomas, the limited evidence, and the indefinite, often conflicting recommendations; therefore, it is critical for providers to understand the existing research and guidelines to determine optimal surveillance strategies for their patients.

Unusual abdominal metastases in osteosarcoma

Intraabdominal metastases in the setting of osteosarcoma are very rare. We describe a case of a 17-year-old boy with high-grade right distal femur osteosarcoma who two years after diagnosis developed extensive intra abdominal metastases involving the omentum, peritoneum, bowel serosa, psoas muscles and abdominal soft tissue. Awareness of and surveillance for unusual patterns of metastasis may allow for earlier detection, intervention, and palliative care decision-making, which may affect survival and quality of life. This report underlines the need for prospective studies evaluating surveillance guidelines for patients after medical and surgical management of osteosarcoma, especially in cases complicated by pulmonary metastases.