title: Replacement of the tumor bed following oncoplastic breast-conserving surgery with immediate latissimus dorsi mini-flap.
abstract: The aim of the present study was to evaluate the geographic variability of the tumor bed following oncoplastic breast-conserving surgery (OP-BCS), and to assess its relevance for radiotherapy planning. In this prospective study, pre- and postoperative computerized tomography (CT) scans of 22 patients with early-stage breast cancer were fused. The preoperative gross tumor volume or excisional biopsy cavity were contoured under the guidance of preoperative radiological images. Postoperative lumpectomy cavities were contoured under the guidance of surgical clips. The conformity index (CI) was calculated and defined on a scale between 0 and 1, where 0 indicated no overlap and 1 indicated 100% concordance. Associations between CI and the number of clips, time interval between surgery and CT scans, pathological tumor size and age were assessed using independent sample testing. The median CI was 0.07 (in five cases, 1, and in eight cases, 0). The lumpectomy cavity shifted from the primary location in 36.4% of the cases. Median shifts between the isocenters of pre- and postoperative volumes were measured as 1.02 cm (range, 0.4-4.43 cm) in the x, 1.07 cm (range, 0.05-5.67 cm) in the y, and 1.12 cm (range, 0-3.75 cm) in the z directions. Only the clip number was determined to be significantly associated with CI (P=0.017). Pre- and postoperative tumor bed volumes were fully superposed in five of the 22 cases. The present study has shown that the tumor bed is markedly replaced following OP-BCS with latissimus dorsi mini-flap (LDMF) reconstruction. Special care should therefore be taken when defining the lumpectomy cavity following OP-BCS with LDMF reconstruction.
authors.affiliation: Department of Radiation Oncology, Florence Nightingale Gayrettepe Hospital, Istanbul 34349, Turkey.
authors.forename: Gül
authors.initials: G
authors.lastname: Alço
authors.affiliation: Department of Radiation Oncology, Florence Nightingale Gayrettepe Hospital, Istanbul 34349, Turkey.
authors.forename: Sefik
authors.initials: S
authors.lastname: Igdem
authors.affiliation: Department of Radiation Oncology, Florence Nightingale Gayrettepe Hospital, Istanbul 34349, Turkey.
authors.forename: Sait
authors.initials: S
authors.lastname: Okkan
authors.affiliation: Department of Radiation Oncology, Florence Nightingale Gayrettepe Hospital, Istanbul 34349, Turkey.
authors.forename: Maktav
authors.initials: M
authors.lastname: Dincer
authors.affiliation: Department of Breast Surgery, Florence Nightingale Istanbul Hospital, Istanbul 34387, Turkey.
authors.forename: Dauren
authors.initials: D
authors.lastname: Sarsenov
authors.affiliation: Department of Breast Surgery, Florence Nightingale Istanbul Hospital, Istanbul 34387, Turkey.
authors.forename: Ahmet Serkan
authors.initials: AS
authors.lastname: Ilgun
authors.affiliation: Department of Radiodiagnostics, Florence Nightingale Istanbul Hospital, Istanbul 34387, Turkey.
authors.forename: Filiz
authors.initials: F
authors.lastname: Agacayak
authors.affiliation: Department of Radiodiagnostics, Florence Nightingale Istanbul Hospital, Istanbul 34387, Turkey.
authors.forename: Filiz
authors.initials: F
authors.lastname: Elbüken
authors.affiliation: Department of Radiation Oncology, Florence Nightingale Gayrettepe Hospital, Istanbul 34349, Turkey.
authors.forename: Tulay
authors.initials: T
authors.lastname: Ercan
authors.affiliation: Department of Breast Surgery, Florence Nightingale Istanbul Hospital, Istanbul 34387, Turkey.
authors.forename: Derya
authors.initials: D
authors.lastname: Selamoglu
authors.affiliation: Department of Breast Surgery, Florence Nightingale Istanbul Hospital, Istanbul 34387, Turkey.
authors.forename: Vahit
authors.initials: V
authors.lastname: Ozmen
keywords: breast conserving surgery; clips; image registration; latissimus dorsi mini-flap; oncoplastic surgery; tumor bed