Placement of radiopaque clips for tumor localization in patients undergoing neoadjuvant chemotherapy and breast conservation therapy

Abstract

An electropolymerization of haloalkylhalosilanes (ClRSiCH3Cl2) that possess two types of electroactive sites, that is, the CCl and SiCl bond is described. The one‐pot synthesis method is shown to yield branched polycarbosilanes having a regular carbon block‐spaced silicon backbone structure. A series of branched polycarbosilanes, [RSiCH3]n with R being CH2, C2H4, C3H6, and CH2C6H4C2H4, have been successfully electropolymerized with Mn up to 42,600 Dalton. Experimental and simulation cyclic voltammetry of these monomers and the computational examination of their LUMOs are applied to study the electropolymerization mechanism. The results suggest that polymerization proceeds by iterating steps involving (1) electroreduction of a CCl bond to a carbanion, which is catalyzed by silylanion radical [Cl SiCl(CH3)RCl] and/or Ni(0)/TDA‐1; and (2) nucleophilic attack of carbanions to SiCl bonds of a second monomer or oligomer to extend the polymer chain. The investigation reveals that the R spacer has a considerable impact on the polymerizability of the corresponding monomer. Such interfacial polymerization resembles a template polymerization, leading to unique microstructures that were preserved even after converted to silicon carbide ceramics at high temperatures. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7677–7689, 2008

Surgical Intervention Following Neoadjuvant Chemotherapy in Breast Cancer

“…a retrospective review was done of 373 patients undergoing preoperative chemotherapy followed by lumpectomy to evaluate the need for marker placement. [8] Of the 373 patients studied, 145 had radiopaque markers placed and 228 did not. With a follow up of approximately 4 years, the patients with marker placement had an improved rate of local control versus those that did not have a marker placed (98.6% v 91.7%, P=0.02).…”

Recommendations for research priorities in breast cancer by the Coalition of Cancer Cooperative Groups Scientific Leadership Council: systemic therapy and therapeutic individualization

“…For individuals who are suitable operative candidates, a meta-analysis of nine randomized studies which included 3,946 patients comparing PST with adjuvant chemotherapy showed no difference in recurrence or survival, although PST was associated with an increased risk of loco-regional recurrence [90]. Radio opaque clip placement prior to PST is associated with a lower local recurrence rate in patients who are candidates for breast conservation [91]. Disease is less likely to recur in individuals who exhibit a pathologic complete response (pCR) in the breast [92] or breast and lymph nodes [93,94], making this a short-term surrogate that is potentially useful for predicting long-term outcomes.…”

Recommendations for research priorities in breast cancer by the coalition of cancer cooperative groups scientific leadership council: imaging and local therapy

“…Some studies have shown higher local recurrence rates with breast conservation after neoadjuvant chemotherapy, which may be in part related to difficulty in localizing the tumor by examination or imaging, or tumors that decrease in size in a honey-comb pattern rather than a concentric pattern. Some have advocated placement of clips in the tumor bed prior to (or during) neoadjuvant therapy, which has resulted in improved local control rates in some retrospective studies [49].…”