BACKGROUND: Radiation therapy may cause a range of side effects of the skin within the irradiated area. Not of all the reactive effects of the skin induced by radiation therapy have to be related to some forms of radiodermatitis, and when non-standard clinical presentations overcome, it may be necessary to undertake appropriate diagnostic tools to not be in trap of wrong diagnosis.
UNASSIGNED: A 76 years-old man undertook resection surgery after a neoadjuvant radiation therapy for a soft tissue sarcoma of his groin region. After surgery, he developed an acute skin reaction comparable with a severe form of radiodermatitis. Despite cares, his clinical status got worse. Only skin biopsies guided us to the right diagnosis: it was a form of a bullous pemphigoid induced by radiation therapy. The consequent appropriate treatment was finally resolute.
CONCLUSIONS: These forms have to be recognized in time, to undertake skin biopsies as soon as an evocative clinical presentation appears. The appropriate treatment, which consists in local or systemic corticotherapy, is resolute in most cases.

Malignant Triton tumour (MTT) is a subtype of malignant peripheral nerve sheaths tumour (MPNST) with exclusive heterologous rhabdomyosarcomatous contingent. MTT is rare and of poor prognosis. This entity illustrates the great heterogeneity of MPNST, the diagnosis of which is difficult in the absence of a specific marker, especially in sporadic forms. Although MTT preferentially develop in patients with type 1 neurofibromatosis, sporadic cases may occur. We herein present a case of MTT of the left arm, occurring in a 74-year-old patient, without clinical context of NF1. The fast-growing tumour reached 9.2cm of greater dimension at the time of surgical excision. Histology showed a spindle cell sarcoma with rhabdoid cell areas expressing myogenin. In the absence of neural crest markers expression, the diagnosis of MPNST was based on a significant loss of expression of the histone 3 tri-methylated lysine 27, a classical although not specific epigenetic mark for this sarcoma group, and on the identification of the heterologous rhabdomyosarcomatous contingent, previously described in the context of MTT.

Sarcoma with EWSR1-PATZ1 gene fusion is an exceedingly rare and newly described Ewing-like sarcoma harboring EWSR1 rearrangements involving fusion partners other than ETS family genes. The clinical, histopathologic and immunophenotypic features of cases reported in literature are fairly diverse and not specific. We report a new case report posing real challenges for histological and molecular diagnosis.

BACKGROUND: Extramedullary hematopoiesis is a complication of myeloproliferative neoplasms or of chronic hemolysis. The more frequent localizations are splenic, ganglionic or paraspinal. Rarely, extramedullary hematopoiesis is associated with solid cancer.
METHODS: We report an original case of sarcoma located in an extramedullary hematopoiesis mass in a 72-year-old woman suffering from hereditary spherocytosis. An asymptomatic right paravertebral mass was found in 2004; the biopsy confirmed extramedullary hematopoiesis. In 2016, the patient was hospitalized due to paravertebral pain. Computed tomography showed the extension of the right paraspinal mass to pleura and mediastinum as well as vertebral bone lysis. Positron emission tomography showed an intense hypermetabolism. The biopsy showed undifferentiated sarcoma.
CONCLUSIONS: This case report illustrates the risk of neoplastic transformation of extramedullary hematopoiesis, and the need for a biopsy when confronted to atypical aspect.

We report the case of a patient affected by a voluminous prostatic tumor for which the histological analysis conclude in a stromal tumor of uncertain malignant potential. This type of tumor is rare, but requires to be individualized to differentiate it from a benign prostatic hyperplasia or a sarcoma of the prostate. The therapeutic care must be made keeping in mind the risk of degeneration towards a malignant shape.