Sex disparities in vitamin D status and the impact on systemic inflammation and survival in rectal cancer.

BACKGROUND: We reported previously that rectal cancer patients given curative-intent chemotherapy, radiation, and surgery for non-metastatic disease had enhanced risk of metastatic progression and death if circulating levels of 25-hydroxyvitamin D [25(OH) D] were low. Here we investigated whether the association between the vitamin D status and prognosis pertains to the general, unselected population of rectal cancer patients. METHODS: Serum 25(OH) D at the time of diagnosis was assessed in 129 patients, enrolled 2013-2017 and representing the entire range of rectal cancer stages, and analyzed with respect to season, sex, systemic inflammation, and survival. RESULTS: In the population-based cohort residing at latitude 60°N, 25(OH) D varied according to season in men only, who were overrepresented among the vitamin D-deficient (< 50 nmol/L) patients. Consistent with our previous findings, the individuals presenting with T4 disease had significantly reduced 25(OH) D levels. Low vitamin D was associated with systemic inflammation, albeit with distinct modes of presentation. While men with low vitamin D showed circulating markers typical for the systemic inflammatory response (e.g., elevated erythrocyte sedimentation rate), the corresponding female patients had elevated serum levels of interleukin-6 and the chemokine (C-X-C motif) ligand 7. Despite disparities in vitamin D status and the potential effects on disease attributes, significantly shortened cancer-specific survival was observed in vitamin D-deficient patients irrespective of sex. CONCLUSION: This unselected rectal cancer cohort confirmed the interconnection of low vitamin D, more advanced disease presentation, and poor survival, and further suggested it may be conditional on disparate modes of adverse systemic inflammation in men and women. TRIAL REGISTRATION: ClinicalTrials.gov NCT01816607 ; registration date: 22 March 2013.

The effect of the small amount of formaldehyde in the SurePath liquid when establishing protocols for immunocytochemistry.

BACKGROUND: SurePath® is an ethanol-based liquid fixative. In addition to ethanol, it also contains a small amount of formaldehyde (<0.2%). The aim of this study was to investigate the immunoreactivity of cells stored for different lengths of time in the SurePath liquid. MATERIALS AND METHODS: Rest material from one malignant and three benign effusions were fixed in SurePath for 1-12 days. Cytospins were incubated with cytokeratin 7 antibody (AB) to evaluate the staining intensity of carcinoma cells and benign, reactive mesothelial cells. Protocols varied as to pretreatment and AB incubation time. RESULTS: Reduced immunostaining intensity was seen within 5 days of storage in the SurePath liquid. It was restored when the pretreatment time was prolonged. CONCLUSIONS: The small amount of formaldehyde in the SurePath liquid seems to affect the immunoreactivity. Local immunocytochemistry protocols in the cytology laboratories should consider this when optimizing their procedures. Postfixation with formalin should be omitted.