OBSERVATION:
An 18-year-old woman who suffered from right basi-thoracic pain and
appearance of a swelling at the level of the 10thright rib. Chest CT showed a heterogeneous hyper vascular mass, located
on the 10th right rib and measuring 106 x 93 x 110 mm. The mass was
heterogeneous with several sites of necrosis. There were osteolysis of
the rib with bifocal cortical rupture. The mass was in a tight contact
with the liver through the diaphragm, which was partially invaded.
Surgical biopsy was performed. The mass was composed of small round
cells with round uniform nuclei and PAS positive cytoplasm. Tumor cells
demonstrate a diffuse membranous CD99 positivity. Desmin, myogenin,
chromogranin, synaptophysin and keratin were negatives (Figure 1).
The diagnosis of Ewing’s sarcoma was made. The patient received 6 cycles
of chemotherapy (Vincristine, Ifosfamide, Doxorubicin and Etoposide). A
post therapy Chest CT-scan showed almost the same initial findings
(figure 2). Surgical resection was indicated after multidisciplinary
team discussion. Resection consisted on a total resection of the 10th
right rib with sarcoma, partially extended to the 9th and 11th right
ribs and to the diaphragm. There was no signs of direct extension to the
liver. Chest wall repair was performed with a polypropylene mesh covered
by a latissimus dorsi muscle flap (figure 3).
Postoperative course was uneventful. The pathological examination of the
specimen showed a small cell proliferation with foci of lace-like
osteoid production (Figure 4). Finally, the diagnosis of a 12cm SCO of
the 10th right rib, infiltrating adjacent soft
tissues, with 20% of tumor necrosis was established. Surgical margins
were negative. Adjuvant chemotherapy with Methotrexate (12g/m2) was
indicated after multidisciplinary concertation, in association with
adjuvant radiotherapy (45Gy). Actually, the patient is well, with a good
wound cicatrisation, and no signs of local recurrence.