Observational study to estimate the proportion of surgical site infection following excision of ulcerated skin tumours (OASIS study)

BACKGROUND

Ulceration is a recognized risk factor for surgical site infection (SSI); however, the proportion of patients developing SSI after excision of an ulcerated skin cancer is unknown.

AIM

To determine the proportion of participants with SSI after surgical excision of an ulcerated skin cancer. A secondary aim was to assess feasibility outcomes to inform the design of a randomized controlled trial to investigate the benefits and harms of perioperative antibiotics following excision of ulcerated tumours.

METHODS

This was a multicentre, prospective, observational study of patients undergoing excision of an ulcerated skin cancer between March 2019 and March 2020. Prior to surgical excision, surface swabs of the ulcerated tumours of participants recruited from one centre were undertaken to determine organism growth. At 4 weeks after surgery, all participants were e-mailed or posted the Wound Healing Questionnaire (WHQ) to determine whether they had developed SSI.

RESULTS

In total, 148 participants were recruited 105 (70.9%) males; mean ± SD age 77.1 ± 12.3 years. Primary outcome data were available for 116 (78.4%) participants, of whom 35 (30.2%) were identified as having an SSI using the WHQ with a cutoff score of 8, and 47 (40.5%) were identified with a cutoff score of 6. Using the modified WHQ in participants with wounds left to heal by secondary intention, 33 (28.4%) and 43 (37.1%) were identified to have SSI respectively.

CONCLUSION

This prospective evaluation of SSI identified with the WHQ following excision of ulcerated skin cancers demonstrated a high proportion with SSI. The WHQ was acceptable to patients; however, further evaluation is required to ensure validity in assessing skin wounds.

Should we be imaging lymph nodes at initial diagnosis of early-stage mycosis fungoides? Results from the PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) international study

BACKGROUND

Early-stage mycosis fungoides (MF) includes involvement of dermatopathic lymph nodes (LNs) or early lymphomatous LNs. There is a lack of unanimity among current guidelines regarding the indications for initial staging imaging in early-stage presentation of MF in the absence of enlarged palpable LNs.

OBJECTIVES

To investigate how often imaging is performed in patients with early-stage presentation of MF, to assess the yield of LN imaging, and to determine what disease characteristics promoted imaging.

METHODS

A review of clinicopathologically confirmed newly diagnosed patients with cutaneous patch/plaque (T1/T2) MF from PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) data.

RESULTS

PROCLIPI enrolled 375 patients with stage T1/T2 MF: 304 with classical MF and 71 with folliculotropic MF. Imaging was performed in 169 patients (45%): 83 with computed tomography, 18 with positron emission tomography-computed tomography and 68 with ultrasound. Only nine of these (5%) had palpable enlarged (≥ 15 mm) LNs, with an over-representation of plaques, irrespectively of the 10% body surface area cutoff that distinguishes T1 from T2. Folliculotropic MF was not more frequently imaged than classical MF. Radiologically enlarged LNs (≥ 15 mm) were detected in 30 patients (18%); only seven had clinical lymphadenopathy. On multivariate analysis, plaque presentation was the sole parameter significantly associated with radiologically enlarged LNs. Imaging of only clinically enlarged LNs upstaged 4% of patients (seven of 169) to at least IIA, whereas nonselective imaging upstaged another 14% (24 of 169). LN biopsy, performed in eight of 30 patients, identified N3 (extensive lymphomatous involvement) in two and N1 (dermatopathic changes) in six.

CONCLUSIONS

Physical examination was a poor determinant of LN enlargement or involvement. Presence of plaques was associated with a significant increase in identification of enlarged or involved LNs in patients with early-stage presentation of MF, which may be important when deciding who to image. Imaging increases the detection rate of stage IIA MF, and identifies rare cases of extensive lymphomatous nodes, upstaging them to advanced-stage IVA2.

The PROCLIPI international registry of early-stage mycosis fungoides identifies substantial diagnostic delay in most patients

BACKGROUND

Survival in mycosis fungoides (MF) is varied and may be poor. The PROCLIPI (PROspective Cutaneous Lymphoma International Prognostic Index) study is a web-based data collection system for early-stage MF with legal data-sharing agreements permitting international collaboration in a rare cancer with complex pathology. Clinicopathological data must be 100% complete and in-built intelligence in the database system ensures accurate staging.

OBJECTIVES

To develop a prognostic index for MF.

METHODS

Predefined datasets for clinical, haematological, radiological, immunohistochemical, genotypic, treatment and quality of life are collected at first diagnosis of MF and annually to test against survival. Biobanked tissue samples are recorded within a Federated Biobank for translational studies.

RESULTS

In total, 430 patients were enrolled from 29 centres in 15 countries spanning five continents. Altogether, 348 were confirmed as having early-stage MF at central review. The majority had classical MF (81·6%) with a CD4 phenotype (88·2%). Folliculotropic MF was diagnosed in 17·8%. Most presented with stage I (IA: 49·4%; IB: 42·8%), but 7·8% presented with enlarged lymph nodes (stage IIA). A diagnostic delay between first symptom development and initial diagnosis was frequent [85·6%; median delay 36 months (interquartile range 12-90)]. This highlights the difficulties in accurate diagnosis, which includes lack of a singular diagnostic test for MF.

CONCLUSIONS

This confirmed early-stage MF cohort is being followed-up to identify prognostic factors, which may allow better management and improve survival by identifying patients at risk of disease progression. This study design is a useful model for collaboration in other rare diseases, especially where pathological diagnosis can be complex.

Phenolic antioxidants attenuate neuronal cell death following uptake of oxidized low-density lipoprotein

Oxidative stress is implicated in neuronal loss associated with neurodegeneration such as in Parkinson's disease, Alzheimer's disease and age-related cognitive decline. Recent reports indicate that the consumption of flavonoid-rich fruits partly reverses the age-related neuronal and cognitive decline. In this study, cultured striatal neurons were exposed to oxidized lipids in the form of low-density lipoprotein (oxLDL) as a model for the induction of oxidative injury, and the abilities of phenolic antioxidants, flavonoids and hydroxycinnamic acid derivatives, to attenuate this neuronal damage were examined. OxLDL was demonstrated to enter neuronal cells and to be capable of eliciting neurotoxicity in a dose- and time-dependent manner, inducing DNA fragmentation and cell lysis. Flavonoids exert protective effects, which appear to be related to specific structural characteristics, particularly relevant being those defining their reduction potentials and partition coefficients. In summary, these data suggest a possible role for flavonoids in reducing neurodegeneration associated with chronic disorders in which oxidative stress is implicated.

Activation of alveolar macrophages and peripheral red blood cells in rats exposed to fibers/particles

The cytotoxic and oxidative responses of crocidolite and chrysotile asbestos fibers and ultrafine titanium dioxide (UF-TiO2) particles were measured in alveolar macrophages (AM) and peripheral red blood cells (RBC) of rat after 30 days with a single intratracheal exposure (5 mg). The following responses were observed one month after fiber/particle instillation: (1) AM population increased; (2) lactate dehydrogenase and acid phosphatase activities in cell free lung lavage fluid increased; (3) substances that react with hydrogen peroxide or thiobarbituric acid were elevated in both AM and peripheral RBC; (4) glutathione peroxidase, glutathione reductase, and catalase were altered in both AM and peripheral RBC; (5) glutathione and ascorbic acid decreased in both AM and peripheral RBC. A significant difference from negative controls was noted in all responses of the two fiber-exposed groups, and in most responses of the UF-TiO2-exposed group. The level of responses to the three test substances suggested a decreasing order of toxicity, with crocidolite > chrysotile > UF-TiO2.

Cytotoxicity, pro-oxidant effects and antioxidant depletion in rat lung alveolar macrophages exposed to ultrafine titanium dioxide

In order to understand the pulmonary toxicity of ultrafine titanium dioxide (UF-TiO2) particles, various biochemical and chemical parameters were assayed in rat alveolar macrophages (AMs) and cell-free lavage fluid. Single intratracheal exposure of UF-TiO2 (2 mg per rat) caused cytotoxicity to pulmonary AMs. An increase in the population of AMs could be observed, followed by increased activities of lactate dehydrogenase and acid phosphatase in cell-free lavage fluid. In addition, AMs showed an adaptive response because the activities of glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase and glutathione S-transferase were increased in these cells. However, this enhancement of antioxidant enzymes could not diminish the enhanced lipid peroxidation and increased rate of hydrogen peroxide generation. The level of glutathione remained decreased in UF-TiO2-exposed rat AMs. The data suggest that the induction of antioxidant enzymes by these cells for self-protection is not sufficient to cope against the toxic action of UF-TiO2, which may lead to oxidative stress.

Inhibition of serum-induced proliferation of bovine tracheal smooth muscle cells in culture by heparin and related glycosaminoglycans

1. The effect of heparin and related glycosaminoglycans on bovine airway smooth muscle proliferation has been investigated. 2. Foetal bovine serum stimulated division of bovine trachealis smooth muscle cells in a concentration-dependent fashion at concentrations between 1 and 30%. 3. Heparin (0.1-100 micrograms ml-1), heparan sulphate (0.1-100 micrograms ml-1) and fragmin (0.1-100 micrograms ml-1) inhibited smooth muscle division in a concentration-dependent fashion between 0.1-100 micrograms ml-1. A heparin disaccharide did not exhibit inhibition of division at 100 micrograms ml-1. 4. Dextran sulphate at molecular weights of 5 x 10(3) and 5 x 10(5) concentration-dependently inhibited division between 0.1-100 micrograms ml-1. Dextran without sulphation did not exhibit inhibition of division at 100 micrograms ml-1. 5. The magnitude of inhibition of proliferation did not reach 100% for any compounds examined at concentrations up to 100 micrograms ml-1 during incubations for 5 and 14 days. IC50 values for inhibition of proliferation ranged between 1-5 micrograms ml-1. 6. These findings suggest that heparin and related glycosaminoglycans inhibit bovine airway smooth muscle cell division.

Distribution of chymase-containing mast cells in human bronchi

Mast cell chymase stimulates secretion from cultured airway gland serous cells and hydrolyzes bronchoactive peptides in vitro. To explore the likelihood of these interactions occurring in situ, we examined the distribution and concentration of chymase-containing mast cells near glands and smooth muscle of major human bronchi from eight individuals without known airway disease. Total airway mast cells and the subset of mast cells containing chymase were detected by staining for methylene blue metachromasia and chloroacetate esterase activity, respectively. The percentage of chymase-containing mast cells was found to differ strikingly among bronchial tissue compartments. Near glands, for example, the concentration of chymase-positive mast cells (640 +/- 120 cells/mm3) was 73 +/- 9% that of total mast cells (910 +/- 130 cells/mm3), whereas in smooth muscle the concentration of chymase-positive mast cells (450 +/- 200 cells/mm3) was only 14 +/- 4% that of total mast cells (2920 +/- 620 cells/mm3). Of all chymase-containing mast cells in the airway subepithelium, 30 +/- 4% were located within 20 microns of submucosal glands. Although the percentage of chymase-containing cells varied, the absolute concentration of chymase-containing mast cells was similar in all compartments. These results reveal a differential distribution of mast cell subpopulations in human airway and suggest that mast cells containing chymase are near gland and smooth muscle targets.