Subcutaneous nodules as initial metastatic sites in osteosarcoma
Authors: Stavrakakis John , Toumbis‐Ioannou Eugenia , Alexopoulos Athanasios , Rigatos Gerassimos A. 
Published: August 2010

A 54‐year‐oid woman presented with two nonsymptomatic subcutaneous nodules. Approximately 3 months previously, after sustaining a fall, her X‐rays revealed a pathologic fracture and a highly destructive appearing lesion. She underwent amputation of the right leg up to the middle of the femoral bone. Her history was negative for any pre‐existing bone condition and her famiiy history was negative for malignant diseases. The pathology report macroscopically showed a neoplastic tumor with a maximal diameter of 12 cm which literally occupied almost all of the knee arthrosis and extended into the femoral condylus. Microscopic examination of the specimen showed a high grade malignant sarcoma comprising mainly spindle cells with a large percentage of necrosis. The exact histologic typing was uncertain, but was probably fibroblastic‐type osteosarcoma (Fig. 1).

On admission, her physical examination was significant for the presence of two subcutaneous nodules. One nodule was located on the abdominal wall in the lower left area (approximately 1×1 cm) and the other on the apex area of the scalp (approximately 1.5x1.5 cm). These lesions were not ulcerated and there was no change in skin pigmentation. The patient mentioned that they appeared a couple of months ago. She also complained of recent dim vision in the left eye.

Laboratory findings included a positive fine needle aspiration (FNA) of both nodules showing metastatic infiltration of the skin and subcutaneous tissue by osteosarcoma (Fig. 2), as well as a positive computed tomography (CT) scan of the orbita showing a metastatic tumor retro‐ocularly to the left which pressed against the optic nerve and was in contact with the lateral rectus. It is noteworthy to point out that, in this patient, both chest roentgenogram and CT of the chest were negative. Bone scan, liver ultrasound, and CT of the upper and lower abdomen were also negative. All other laboratory findings were within normal limits.

The decision was made that the patient was to undergo chemotherapy consisting of two cycies of Adriamycin (ADR) and Piatamine (CDDP), 21 days apart, followed by one cycle of BCD (Bleomycin, Cyclophosphamide, and Dactinomycin) after 21 days. This regimen was to be repeated once for a total of six cycles, each 21 days apart.

One day prior to the commencement of chemotherapy, a third subcutaneous nodule presented on the right side of the back in the scapular area. This also had a positive FNA showing metastatic osteosarcoma.

On admission of the patient for the second cycle of chemotherapy (ADR and CDDP), a fourth nodule was discovered on the upper third of the left thigh, and on admission for the third cycle (BCD), a fifth nodule was found on the left arm (brachium area). The patient's‐chest roentgenogram continued to be negative.

A little over ½ months after initiating chemotherapy, on entering the fourth cycle (ADR and CDDP), it was observed that two of the five nodules (on the left arm and in the left lower abdominal area) had disappeared. There was also a decrease in the size of the remaining three. Furthermore, the patient mentioned improvement with regard to her vision.

At the time of admission for the fifth cycle of chemotherapy (ADR and CDDP), all nodules, except that on the apex area of the scalp, had disappeared. The remaining nodule was stable in size and, on admission for the sixth cycle (BCD), had decreased in size.

One month following the sixth cycle of chemotherapy, the patient was admitted for follow‐up. All five subcutaneous nodules (Fig. 3) had clinically completely disappeared. Furthermore, the patient mentioned complete restoration of her vision. The laboratory tests (bone scan, liver ultrasound, orbital CT, CT of the upper and lower abdomen, and thoracic CT) were all negative. At present the patient is in remission with regard to her disease and in general good health.