Effect of neoadjuvant chemotherapy on breast tissue composition: a longitudinal mammographic study with automated volumetric measurement.

OBJECTIVES: To investigate the effect of neoadjuvant chemotherapy (NAC) on breast tissue composition with mammographic automated volumetric measurement. METHODS: This retrospective study included 168 breast cancer patients who were treated with NAC and underwent serial mammography (pre-treatment, mid-treatment, and post-treatment) between January 2015 and October 2018. Automated volumetric measurements of the contralateral breast volume (BV), fibroglandular volume (FGV), and breast density (BD) were performed using Volpara software. BD grades were divided into 4 groups by Volpara density grade (VDG). The longitudinal changes in BV, FGV, BD, and their associated factors were evaluated. RESULTS: Repeated-measures analysis of variance demonstrated a significant reduction in BV, FGV, and BD over time (p < 0.001, p < 0.001, and p = 0.002, respectively). BV showed a greater reduction in the second half than in the first half (- 28.6 cm3 vs. - 15.2 cm3), BD showed a greater reduction in the first half than in the second half (- 0.8% vs. - 0.1%), and FGV steadily decreased (- 4.6 cm3 and - 3.9 cm3 in the first and second halves). On multivariable linear regression analysis, chemotherapy regimen was associated with BV change between pre- and post-treatment (p = 0.002); age (p = 0.024) and VDG (p = 0.027) were associated with FGV change; age (p = 0.037), VDG (p = 0.002), and chemotherapy regimen (p = 0.003) were associated with BD change. CONCLUSIONS: NAC affects breast tissue composition, reflected as reductions in BV, FGV, and BD. Mammography with automated volumetric measurement can capture quantitative changes in these breast tissue parameters during NAC. KEY POINTS: • Neoadjuvant chemotherapy (NAC) affects breast tissue composition with different patterns of reduction in breast volume, fibroglandular volume, and breast density. • Age, Volpara density grades, and NAC regimen were independent factors associated with breast density change between pre-treatment and post-treatment. • Mammography with automated volumetric measurement enables identification of longitudinal changes in breast tissue composition.

Location of positive surgical margin and its association with biochemical recurrence rate do not differ significantly in four different types of radical prostatectomy.

PURPOSE: To analyze the location of the positive surgical margin (PSM) and its association with the biochemical recurrence (BCR) rate in cases of radical prostatectomy (RP) according to the type of surgery. MATERIALS AND METHODS: We retrospectively analyzed 1,880 cases of RP. Baseline characteristics were analyzed. Locations of the PSM were recorded in the four surgery groups as apex, anterior, posterolateral, and base and were analyzed by using chi-square test. The association of the location of the PSM with the BCR rate was analyzed by using Kaplan-Meier survival analysis according to the type of surgery, which included radical perineal prostatectomy (RPP, n=633), radical retroperitoneal prostatectomy (RRP, n=309), laparoscopic radical prostatectomy (LRP, n=164), and robot-assisted laparoscopic radical prostatectomy (RALRP, n=774). RESULTS: A PSM was found in a total of 336 cases (18%): 122 cases of RPP (18%), 67 cases of RRP (17%), 29 cases of LRP (17%), and 119 cases of RALRP (15%). The PSM rate did not differ significantly by surgical type (p=0.142). The location of the PSM was the apex in 136 cases (7.2%), anterior in 67 cases (3.5%), posterolateral in 139 cases (7.3%), and base in 95 cases (5.0%), and showed no significant difference according to surgical type (p=0.536, p=0.557, p=0.062, and p=0.109, respectively). The BCR rate according to the location of the PSM did not differ significantly for the four types of surgery (p=0.694, p=0.301, p=0.445, and p=0.309 for RPP, RRP, LRP, and RALRP, respectively). CONCLUSIONS: The location of the PSM seemed to be unrelated to type of RP. There was no significant correlation between the BCR rate and the location of the PSM for any of the RP types.

Comparison of perioperative outcomes of robotic versus laparoscopic partial nephrectomy for complex renal tumors (RENAL nephrometry score of 7 or higher).

PURPOSE: To compare the perioperative outcomes of laparoscopic partial nephrectomy (LPN) and robotic partial nephrectomy (RPN) for moderately or highly complex tumors (RENAL nephrometry score ≥ 7). MATERIALS AND METHODS: A retrospective analysis was performed for 127 consecutive patients who underwent either LPN (n=38) or RPN (n=89) between 2007 and 2013. Perioperative outcomes were compared. RESULTS: There were no significant differences between the two groups with respect to patient gender, laterality, RENAL nephrometry score, or body mass index. The RPN group had a slightly higher RENAL nephrometry score (7.8 vs. 7.5, p=0.061) and larger tumor size (3.0 cm vs. 2.5 cm, p=0.044) but had a lower Charlson comorbidity index (3.7 vs. 4.4, p=0.017) than did the LPN group. There were no significant differences with respect to warm ischemia time, estimated blood loss, intraoperative complications, or operative time. Only one patient who underwent LPN had a positive surgical margin. There were statistically significant differences in surgical marginal width between the LPN and RPN groups (0.6 cm vs. 0.4 cm, p=0.001). No significant differences in postoperative complications were found between the two groups. Owing to potential baseline differences between the two groups, we performed a propensity-based matching analysis, in which differences in surgical margin width between the LPN and RPN groups remained statistically significant (0.6 cm vs. 0.4 cm, p=0.029). CONCLUSIONS: RPN provides perioperative outcomes comparable to those of LPN and has the advantage of healthy parenchymal preservation for complex renal tumors (RENAL score ≥ 7).