Peripheral leucocyte count variations in rectal cancer treatment

Impaired postoperative leucocyte counts after preoperative radiotherapy for rectal cancer in the Stockholm III Trial

BACKGROUND

Radiotherapy (RT) in rectal cancer increases postoperative morbidity. A suggested reason is RT-induced bone marrow depression resulting in impaired leucocyte counts. The ongoing Stockholm III Trial randomizes patients with operable rectal cancers to short-course RT with immediate surgery (SRT), short-course RT with surgery delayed for 4-8 weeks (SRT-delay) and long-course RT with surgery delayed for 4-8 weeks (LRT-delay). This study examined differences between the randomization arms regarding leucocyte response and postoperative complications.

METHODS

Patients randomized in the Stockholm III Trial between October 1998 and November 2010 were included. Data were collected in a prospective register. Additional data were obtained by retrospective review of clinical records.

RESULTS

Of 657 randomized patients, 585 had data on leucocytes. The SRT arm had the highest proportion of postoperative complications (SRT, 52·5 per cent; SRT-delay, 39·4 per cent; LRT-delay, 41 per cent; P = 0·010). There was no association between low preoperative leucocyte count and postoperative complications (P = 0·238). Irrespective of randomization arm, patients with an impaired postoperative to preoperative leucocyte ratio had the highest rate of complications (low ratio, 56·6 per cent; intermediate ratio, 46·9 per cent; high ratio, 36·3 per cent; P = 0·010). The SRT arm had the highest proportion of low ratios (SRT, 48·9 per cent; SRT-delay, 22·8 per cent; LRT-delay, 22 per cent; P < 0·001).

CONCLUSION

An impaired postoperative leucocyte response is associated with postoperative complications. The highest risk is with immediate surgery following short-course radiotherapy.

REGISTRATION NUMBER

NCT 00904813 (http://www.clinicaltrials.gov).

Neoadjuvant chemoradiotherapy, sepsis and neutrophil levels following radical excision of rectal cancer

PURPOSE

This study aimed to determine differences in neutrophil levels between those receiving long-course neoadjuvant chemoradiotherapy (nCXRT) and those proceeding straight to surgery (StS) for rectal cancer, and in those who developed serious septic events within 30 post-operative days within each group.

METHOD

Patients undergoing elective surgery between 2006 and 2008 were retrospective reviewed. Some 38 received nCXRT, and 46 proceeded StS. Statistical techniques included repeated measures analyses.

RESULTS

There was no significant difference in serious 30-day septic rates (anastomotic leaks, pelvic abscess or generalised sepsis) between treatment groups (nCXRT, 11%; StS, 13%; p = 1.000). Neutrophil levels in the nCXRT group fell significantly and remained lower throughout treatment than those proceeding StS (p < 0.001 within groups, p < 0.001 between groups). The difference in means of the treatment groups was different for those with sepsis than for those without, and the difference in means of those with sepsis and those without is very different for the two treatment groups (p = 0.018).

CONCLUSION

Chemoradiotherapy reduced neutrophil levels throughout treatment, and post-operative septic patients in this group had even lower levels. Further studies are warranted to fully assess the relationship of neutrophil levels to sepsis, using standardised definitions of sepsis.