Breast density, scintimammographic 99mTc(V)DMSA uptake, and calcitonin gene related peptide (CGRP) expression in mixed invasive ductal associated with extensive in situ ductal carcinoma (IDC + DCIS) and pure invasive ductal carcinoma (IDC): correlation wit

Background We evaluated the variation of calcitonin gene related peptide (CGRP) expression in patients with mixed invasive with extensive in situ ductal carcinomas (IDC ? DCIS) and pure IDC, in relation to mammographic breast density (%BD), proliferation-seeking radiotracer 99mTc(V) dimercaptosuccinic acid (DMSA) uptake (scintimammographic-SMM), proliferation index Ki-67, and estrogen receptor (ER) status. We also assessed CGRP expression with histological grade. Methods We studied retrospectively 24 women with suspicious findings on mammography who were evaluated preoperatively with 99mTc(V)DMSA scintimammography. Histology revealed 12 IDC (grade II in 8, grade III in 4 patients; mean size ± SD, 2.6 ± 1.3 cm; mean age ± SD, 66.5 ± 13.1 years) and 12 IDC ? DCIS (grade II in 6, grade III in 6 patients; DCIS component mean size ± SD, 5.3 ± 1.8 cm; IDC component mean size ± SD, 2.5 ± 1.1 cm; mean age ± SD, 58.5 ± 15.1 years). Immunohistochemistry for CGRP, Ki-67, and ER status was performed in all 24 surgical specimens. BD and SMM were calculated by computer-assisted methods and were statistically correlated with CGRP expression. BD, SMM, Ki-67, and ER were statistically compared between IDC and IDC ? DCIS, whereas CGRP, Ki-67, and ER were compared between patients with BD [25 and \25%. CGRP was also compared (t test) between grade II and grade III in both groups. Results Overall positive correlation was found between BD and CGRP (r = 0.577, P\0.001). Positive correlation was established between SMM and CGRP only in IDC ? DCIS (rSMM(IDC?DCIS)–CGRP = 0.634, P\0.05). CGRP and Ki-67 were significantly higher in patients with BD [25% compared with \25% BD patients (P = 0.00008 and P = 0.014, respectively). BD and SMM were significantly higher in CGRP(?) than in CGRP(-) patients as well as in IDC ? DCIS compared with IDC. Ki-67 was significantly higher, whereas ER was significantly lower, in IDC ? DCIS than in IDC. In all patients, CGRP was significantly higher in grade II as compared with grade III (P = 0.005). In the mixed group (IDC ? DCIS), grade II cancers had also significantly higher CGRP values as compared with grade III ones