The Role of Adjuvant Radiotherapy for a Case of Primary Breast Sarcoma: A Plan Comparison between Three Modern Techniques and a Review of the Literature

Abstract

A 65-year-old woman, affected by a malignant fibrous histiocytoma (undifferentiated pleomorphic sarcoma) of the left breast, presented to our department to receive the postoperative radiotherapy. In the absence of prospective and randomized trials and investigations on breast sarcoma irradiation in literature, due to the rarity of this pathology, the role of adjuvant radiotherapy remains unclear. To identify the best radiotherapy technique for this patient, three methods were compared: 3D conformal radiotherapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and volumetric arc therapy (VMAT) or RapidArc® (RA). 50 Gy was prescribed to the chest wall and 66 Gy to the tumor bed. Three plans were designed, and target coverage, organs-at-risk sparing, and treatment efficiency were compared. IMRT and RA improved both target coverage and dose uniformity/homogeneity. Planning objective for the lung is always satisfied comparing the different techniques, but the volume receiving 20 Gy drops to 17% by RA compared to 3D-CRT. The heart volume receiving 30 Gy was 10% by IMRT, against 13% and 16% by RA and 3D-CRT. The monitor unit (MU) required by 3D-CRT was 527 MU, followed by RA and IMRT. Treatment time was similar with 3D-CRT and RA but doubled using IMRT. Although all three radiotherapy techniques offered a satisfactory solution, RA and IMRT offer some improvement on target coverage, dose homogeneity, and conformity for this particular case of breast sarcoma.

Primary Undifferentiated Pleomorphic Sarcoma of the Breast; a Case Report with Literature Review of Similar Cases

“…Considering the risk of recurrence and metastasis, we suggested adjuvant chemotherapy after total mastectomy. Adjuvant radiotherapy ( 14 , 22 ) or chemotherapy ( 18 ) for patients with breast UPS, has been reported only in a few cases and the most appropriate treatment strategy has remained uncertain and needs to be explored using further cases. Sufficient excision of the primary breast tumor with free-of-tumor margins would be necessary.…”

Peripheral Neural Sheath Breast Sarcoma: Case Report and Literature Review

“…However, the low number of patients is likely partly responsible for this result [ 25 ]. Finally, when administering adjuvant RT to patients MPNS sarcomas of the breast, the treatment must ensure an efficient target area of coverage with high doses, generally between 50 and 60 Gy, to guarantee better local control [ 26 ].…”

Radiation-induced undifferentiated pleomorphic sarcoma of the breast

“…Our case demonstrated that with a missed diagnosis, within 6 months, tumour size can more than double. Adjuvant radiation and chemotherapy may benefit patients with high-grade features 17 38. Although there have been limited studies on biological markers as prognostic factors, high Ki-67 has been shown to be a poor prognostic factor that is associated with higher risk of local recurrence, distant metastasis and poor prognosis in primary UPS of the breast 15.…”