Massive bone marrow involvement by clear cell variant of rhabdomyosarcoma

Spontaneous tumor lysis syndrome in an adult with alveolar rhabdomyosarcoma: a challenging diagnosis

Tumor lysis syndrome (TLS) is an oncological emergency characterized by metabolic and electrolyte imbalances associated with the rapid destruction of tumor cells. It is commonly recognized when cytotoxic treatment for hematological malignancies is initiated. Spontaneous TLS with solid tumors like rhabdomyosarcoma (RMS) is exceedingly rare. It has been noted that the highest incidence of this tumor occurs in individuals under the age of 20 years, with an incidence rate of 4.4 cases per 1 million. Here, we present the case of a 22-year-old male who presented with spontaneous clinical TLS. A computed tomography (CT) scan revealed a large pelvic mass, diffuse lymphadenopathy, and infiltration of the ocular muscles. Subsequently, a biopsy was conducted, and the histopathological results indicated alveolar rhabdomyosarcoma. Our literature review revealed five cases of spontaneous TLS caused by RMS, with our patient being the only adult among all published cases.

Rhabdomyosarcoma with unknown primary tumor site: A report from European pediatric Soft tissue sarcoma Study Group (EpSSG)

BACKGROUND

Rhabdomyosarcoma (RMS) is an aggressive malignancy, and 20% of children present with metastases at diagnosis. Patients presenting with disseminated disease very occasionally have no clear evidence of a primary tumor mass. As these patients have rarely been investigated, we report on a series of patients with RMS and unknown primary tumor site registered in the Metastatic (MTS) RMS 2008 protocol (October 2008 to December 2016) coordinated by the European pediatric Soft tissue sarcoma Study Group.

METHODS

Patients were administered nine cycles of induction chemotherapy, and 48 weeks of maintenance chemotherapy. Surgery and/or radiotherapy were planned after the first assessment of tumor response, and implemented after six cycles of chemotherapy. If feasible, radiotherapy to all sites of metastasis was recommended.

RESULTS

We identified 10 patients with RMS and unknown primary site, most of them adolescents (median age 15.8 years, range: 4.6-20.4). Nine had fusion-positive alveolar RMS. Multiple organ involvement was identified in seven patients, two only had bone marrow disease, and one only had leptomeningeal dissemination. All patients were given chemotherapy, four were irradiated, and none had surgery. Three patients underwent allogeneic bone marrow transplantation. At the time of this analysis, only two patients are alive in complete remission: one had received radiotherapy; and one had a bone marrow transplant.

CONCLUSIONS

RMS with unknown primary tumor occurs mainly in adolescents and is typically fusion-positive alveolar. Radiotherapy may be important, but survival is poor and patients should be offered enrollment in investigational trials.

Treatment Strategy of Metastatic Nasopharyngeal Carcinoma With Bone Marrow Involvement—A Case Report

Bone marrow involvement (BMI) of solid tumors is a special type of distant metastasis. It has an occult onset, atypical clinical and laboratory features, and a high mortality. We present a nasopharyngeal carcinoma case with cervical and axillary lymph nodes, bilateral lung, multiple bone, and bone marrow metastases, who was treated chemotherapy plus targeted therapy under the guidance of a patient-derived tumor xenograft (PDTX) model, followed by maintenance chemotherapy plus immunotherapy. The patient’s symptoms were relieved after four cycles of chemotherapy plus targeted therapy. His bone marrow biopsy turned negative after 7 months of therapy. In addition, his total peripheral T cells as well as the proportion of CD8⁺ T cells increased during the course of therapy. The combination of chemotherapy, targeted therapy, and immunotherapy provides an effective antitumor regimen for advanced NPC patients with BMI.

Primary alveolar rhabdomyosarcoma of the bone: two cases and review of the literature

BACKGROUND

Rhabdomyosarcoma (RMS) is a malignant tumor of mesenchymal origin and comprises the largest category of soft-tissue sarcomas both in children and adolescents. From a pediatric oncology point of view, RMS has traditionally been classified into alveolar (ARMS) and embryonal (ERMS) subtypes. The anatomical localization of the tumor may vary, but commonly involve the head/neck regions, male and female urogenital tract or the trunk and extremities.

CASE PRESENTATION

Here, we report two challenging cases involving 17- and 9-years-olds males where diffuse and multiplex bone lesions suggested either a hematological disease or a primary bone tumor (mesenchymal chondrosarcoma). Biopsies, proved a massive infiltration of the bone marrow cavity with rhabdomyosarcoma. In both cases, the ARMS subtype was confirmed using FOXO1 break-apart probes (FISH). Radiological examination could not identify primary soft tissue component in any localization at the time of diagnosis in either cases.

CONCLUSIONS

Primary alveolar rhabdomyosarcoma of the bone as a subtype of ARMS, seems to be a distinct clinico-pathological entity with challenging diagnostic difficulties and different, yet better, biological behavior in comparison to soft tissue ARMS. However, it is difficult to be characterized or predict its prognosis and long-term survival as only sporadic cases (four) were reported so far.

Rhabdomyosarcoma infiltrating bone marrow

We present a case of 26-year-old male, previously diagnosed as rhabdomyosarcoma (RMS) of perineal region. The peripheral smear showed a leukoerythroblastic picture with an occasional atypical cell. The bone marrow aspirate and biopsy showed monotonous sheets of malignant cells. On immunohistochemistry the tumor cells were strongly positive for desmin and negative for CD34 and CD117. This case illustrates the morphology and IHC findings in a case of RMS. Immunostains like CD34 and CD117 should be included to rule out a possibility of acute leukemia.

Cranial metastatic alveolar rhabdomyosarcoma mimicking hematological malignancy in an adolescent boy

BACKGROUND

Widespread alveolar rhabdomyosarcoma (ARMS) with bone marrow involvement and with an unknown primary tumor, especially presenting with acute tumor lysis syndrome can be easily misdiagnosed as a hematological malignancy. Furthermore, brain metastasis of ARMS is rare seen in children.

CASE REPORT

Herein, we report a 14-year-old boy presenting with acute tumor lysis syndrome due to bone marrow invasion of ARMS, who was diagnosed after abdominal paraaortic lymph node biopsy. Despite radiological and nuclear medicine imaging, the primary tumor site could not be found. He was treated with vincristine, topotecan, and cyclophosphamide for 42 weeks. Six months after the completion of treatment, he suffered from severe headache, blurred vision, right hemiplegia, and severe bone pain. Cranial magnetic resonance imaging showed multiple hemorrhagic infarctions. Brain biopsy showed brain metastasis with PAX3-FKHR fusion transcript.

CONCLUSION

The clinicians must be vigilant about solely brain metastasis in ARMS without additional metastasis.