A comparative study of perioperative techniques to attain negative margins and spare healthy breast tissue in breast conserving surgery

BACKGROUND AND AIM

Traditionally lumpectomy as a part of breast-conserving surgery (BCS) is performed by palpation-guided method leading to positive margins and large excision volumes. There is no evidence suggesting that wide margin excisions decrease intra-breast tumour recurrence. Various perioperative techniques are used for margin assessment. We aimed to compare three commonly used techniques, i.e., ultrasound-guided surgery, palpation-guided surgery and cavity shaving for attaining negative margins and estimating the extent of healthy breast tissue resection.

METHOD

A prospective comparative study was performed on 90 patients who underwent breast conservation surgery for early breast cancer between August 2018 and June 2019. Tumour excision with a minimum of 1 cm margin was done either using ultrasound, palpation or cavity shaving. Histopathological evaluation was done to assess the margin status and excess amount of resected normal breast tissue. Calculated resection ratio (CRR) defining the excess amount of the resected breast tissue was achieved by dividing the total resection volume (TRV) by optimal resection volume (ORV). The time taken for excision was also recorded.

RESULTS

Histopathology of all 90 patients (30 in each group) revealed a negative resection margin in 93.3% of 30 patients in palpation-guided surgery group and 100% in both ultrasound-guided surgery and cavity shaving groups. Two patients (6.7%) from the cavity shaving group had positive margins on initial lumpectomy but shave margins were negative. TRV was significantly less in the ultrasound-guided surgery group compared to the palpation-guided surgery group and cavity shaving group (76.9 cm3, 94.7 cm3 and 126.3 cm3 respectively; p < 0.0051). CRR was 1.2 in ultrasound group compared to 1.9 in palpation group and 2.1 in cavity shave group which was also statistically significant (p < 0.0001).Excision time was significantly less (p < 0.001) in palpation-guided surgery group (13.8 min) compared to cavity shaving group (15.1 min) and ultrasound-guided group (19.4 min).

CONCLUSION

Ultrasound-guided surgery is more accurate in attaining negative margins with the removal of least amount of healthy breast tissue compared to palpation-guided surgery and cavity shaving.

Streptococcus pseudopneumoniae: an emerging respiratory tract pathogen

BACKGROUND & OBJECTIVES

Streptococcus pseudopneumoniae a member of the Viridans Streptococci, is known to be associated with chronic obstructive pulmonary disease and respiratory tract infections (RTI). Very scanty information is available on the isolation of S. pseudopneumoniae from India. Hence, the present study was an attempt to isolate S. pseudopneumoniae from clinical samples and to study their drug resistance pattern.

METHODS

Sputum samples (n=150) submitted to the microbiology laboratory for routine culture from patients clinically suspected to have lower respiratory tract infection were inoculated onto sheep blood agar and chocolate agar plates. Alpha haemolytic colonies were identified as S. pseudopneumoniae based on absence of capsule, bile solubility and optochin susceptibility in 5 per cent CO₂ and ambient air. Disk diffusion method was used for antibiotic susceptibilily testing.

RESULTS

Among the samples screened, 4 per cent showed the growth of only S. pseudopneumoniae. Other pathogens isolated were Streptococcus pneumoniae, Moraxella catarrhalis, Klebsiella spp., Enterococcus spp., Pseudomonas spp., Haemophilus influenzae, Staphylococcus aureus, Candida albicans. All the S. pseudopneumoniae isolates were resistant to erythromycin.

INTERPRETATION & CONCLUSIONS

Our preliminary results showed presence of S. pseudopneumoniae in this part of the country and these were associated with RTI. Currently, most clinical laboratories report optochin susceptible isolates in 5 per cent CO₂ as S. pneumoniae and the resistant ones are not further tested for susceptibility in ambient air. As a result, S. pseudopneumoniae may be missed out. Hence, performance of at least two tests, viz. optochin susceptibility with incubation in 5 per cent CO₂ and ambient air along with bile solubility is necessary to differentiate S. pneumoniae from S. pseudopneumoniae.