Setting up regional diagnostic reference levels for pediatric interventional cardiology in Latin America and the Caribbean countries: preliminary results and identified challenges

The goal of the present study was to propose a set of preliminary regional diagnostic reference levels (DRLs) for pediatric interventional cardiology (IC) procedures in Latin America and the Caribbean countries, classified by age and weight groups. The study was conducted in the framework of the Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean program coordinated by the World Health Organization and the Pan American Health Organization in cooperation with the International Atomic Energy Agency. The first step of the program was focused on pediatric IC. Dose data from diagnostic and therapeutic procedures were collected between December 2020 and December 2021. Regional DRLs were set as the third quartile of patient dose data (kerma area product) collected in 18 hospitals from 10 countries in an initial sample of 968 procedures. DRLs were set for four age bands and five weight ranges. The values obtained for the four age bands (<1 yr, 1 to <5 yr, 5 to <10 yr and 10 to <16 yr) were 2.9, 6.1, 8.8 and 14.4 Gy cm²for diagnostic procedures, and 4.0, 5.0, 10.0 and 38.1 Gy cm²for therapeutic procedures, respectively. The values obtained for the five weight bands (<5 kg, 5 to <15 kg, 15 to <30 kg, 30 to <50 kg and 50 to <80 kg) were 3.0, 4.5, 8.1, 9.2 and 26.8 Gy cm²for diagnostic procedures and 3.7, 4,3, 7.3, 16.1 and 53.4 Gy cm²for therapeutic procedures, respectively. While initial data were collected manually as patient dose management systems (DMSs) were not available in most of the hospitals involved in the program, a centralized automatic DMS for the collection and management of patient dose indicators has now been introduced and is envisaged to increase the sample size. The possibility of alerting on high dose values and introducing corrective actions will help in optimization.

Stereotactic body radiation therapy for liver metastasis from colorectal cancer: size matters

PURPOSE

We analysed our initial experience with SBRT in liver metastasis from colorectal cancer at our institution.

MATERIALS AND METHODS

Between January/2014 and December/2017, 22 patients with 31 LMCCR were treated. Local control (LC) was assessed using the Kaplan-Meier and log-rank tests. We analysed potential prognostic factors for LC: sex, PTV size, number of LM and the radiation scheme.

RESULTS

Median age: 69 years. Prior chemotherapy or local liver treatments: 81.8% and 63.6% of patients, respectively. SBRT consisted of 3 × 20 Gy (42.9%) and 3 × 15 Gy (31.4%). There were 88.5% responses (57.1% CR and 31.4% PR). Median follow-up was 30 months. LC per lesion at 12 and 24 months was 85.3% and 61.8%, respectively. Tumour volumes > 30 cc correlated with worsened 2-year-control rates (90% vs 34.5%) (p = 0.005). There was only a patient with CTC-grade 3 toxicity.

CONCLUSIONS

Liver SBRT is a safe and effective treatment that achieves high local control rates. We found a significant correlation between larger LMCRC and worse local control.

High-pressure homogenization and high hydrostatic pressure processing of human milk: Preservation of immunological components for human milk banks

Human milk (HM) constitutes the first immunological barrier and the main source of nutrients and bioactive components for newborns. Immune factors comprise up to 10% of the protein content in HM, where antibodies are the major components (mainly IgA, IgG, and IgM). In addition, antibacterial enzymes such as lysozyme and immunoregulatory factors such as soluble cluster of differentiation 14 (sCD14) and transforming growth factor β2 (TGF-β2) are also present and play important roles in the protection of the infant's health. Donor milk processed in HM banks by Holder pasteurization (HoP; 62.5°C, 30 min) is a safe and valuable resource for preterm newborns that are hospitalized, but is reduced in major immunological components due to thermal inactivation. We hypothesized that high hydrostatic pressure (HHP) and high-pressure homogenization (HPH) are 2 processes that can be used on HM to reduce total bacteria counts while retaining immunological components. We studied the effects of HHP (400, 450, and 500 MPa for 5 min applied at 20°C) and HPH (200, 250, and 300 MPa, milk inlet temperature of 20°C) applied to mature HM, on microbiological and immunological markers (IgA, IgG, IgM, sCD14, and TGF-β2), and compared them with those of traditional HoP in HM samples from healthy donors. The HHP processing between 400 and 500 MPa at 20°C reduced counts of coliform and total aerobic bacteria to undetectable levels (<1.0 log cfu/mL) while achieving approximately 100% of immunological component retention. In particular, comparing median percentages of retention of immunological components for 450 MPa versus HoP, we found 101.5 versus 50.5% for IgA, 89.5 versus 26.0% for IgM, 104.5 versus 75.5% for IgG, 125.0 versus 72.5% for lysozyme, 50.6 versus 0.1% for sCD14, and 88.5 versus 61.1% for TGF-β2, respectively. Regarding HPH processing, at a pressure of 250 MPa and inlet temperature of 20°C, the process showed good potential to reduce coliforms to undetectable levels and total aerobic bacteria to levels slightly above those obtained by HoP. The median percentages of retention of immunological markers for HPH versus HoP were 71.5 versus 52.0%, 71.0 versus 27.0%, 104.0 versus 66.5%, and 30.9 versus 0.2%, for IgA, IgM, IgG, and sCD14, respectively; results did not significantly differ for lysozyme and TGF-β2. The HPH at 300 MPa produced higher inactivation of immunological components, similar to values achieved with HoP.

The blind men and the elephant: Systematic review of systematic reviews of cannabis use related health harms

Cannabis is the third most used psychoactive substance worldwide. The legal status of cannabis is changing in many Western countries, while we have very limited knowledge of the public health impact of cannabis-related harms. There is a need for a summary of the evidence of harms and risks attributed to cannabis use, in order to inform the definition of cannabis risky use. We have conducted a systematic review of systematic reviews, aiming to define cannabis-related harms. We included systematic reviews published until July 2018 from six different databases and following the PRISMA guidelines. To assess study quality we applied the AMSTAR 2 tool. A total of 44 systematic reviews, including 1,053 different studies, were eligible for inclusion. Harm was categorized in three dimensions: mental health, somatic harm and physical injury (including mortality). Evidence shows a clear association between cannabis use and psychosis, affective disorders, anxiety, sleep disorders, cognitive failures, respiratory adverse events, cancer, cardiovascular outcomes, and gastrointestinal disorders. Moreover, cannabis use is a risk factor for motor vehicle collision, suicidal behavior and partner and child violence. Cannabis use is a risk factor for several medical conditions and negative social consequences. There is still little data on the dose-dependency of these effects; evidence that is essential in order to define, from a public health perspective, what can be considered risky use of cannabis. This definition should be based on quantitative and qualitative criteria that informs and permits the evaluation of current approaches to a regulated cannabis market.

[Re-irradiation with SBRT (Stereotactic Body Radiation Therapy) for locoregional unresectable relapse of head and neck cancer: a case report]

Patients with an unresectable recurrence of head and neck carcinoma (HNC) have a poor prognosis, with limited treatment options. Recent technical advances allow radiotherapy (RT) to be handled with great precision, making it possible to re-irradiate recurrent tumors by means of stereotactic body radiotherapy (SBRT) with high doses of RT while protecting healthy tissues near the tumor. Although this technique has been used to irradiate different primary tumors and their metastases, SBRT in HNC has had a much slower evolution than in the mentioned locations. This is due to the difficulties in re-irradiating the HNC, because of the expected toxicity as it is a relatively small area with dense vascularization and innervation, and where several senses are located. We present the first case of a HNC re-irradiated with SBRT in the Complejo Hospitalario de Navarra; the patient showed a complete response and continues to be disease-free sixteen months after the irradiation.

Free Neurocognitive Screening Initiative: An Opportunity to Address Health Disparities and Promote Cultural Competence in Northcentral Florida

Objective

The risk for cognitive impairment is greater in individuals with low SES and limited education. In rural areas, distance and economic concerns preclude individuals from accessing care. In Alachua County, 23% of residents live below poverty and 16% are uninsured. The Neurocognitive Screening Initiative (NSI) attempts to reduce disparities in Alachua by offering free neurocognitive screening. NSI also aspires to promote cultural competence through unique training opportunities for clinical neuropsychology doctoral students.

Method

Patients learned about NSI through flyers, word of mouth, or referrals. Appointments include a clinical interview, cognitive testing, and mood questionnaires. Patients receive feedback, brain health recommendations, and referrals to community resources. Phase 1 began in November 2017 and involved selection of appropriate cognitive measures, development and dissemination of advertising materials, identification of resources, and trainee recruitment. From February 2018 to August 2018, phase 2 involved administration of cognitive screeners. Phase 3 involved continued provision of clinical services, expansion of the NSI team and increased culturally relevant outreach.

Outcomes

NSI’s greatest challenge is recruitment of the appropriate demographic. Since phase 2, we have evaluated 10 patients with diverse racial, socioeconomic, and clinical characteristics. NSI has recruited an ethnoracially diverse cohort of trainees comprised of 4 graduate students and 2 postdoctoral fellows supervised by a clinical neuropsychologist.

Discussion

Efforts to provide services to marginalized individuals have uncovered challenges in attracting patients who might benefit from these services. NSI is forging community partnerships with churches, libraries, and local organizations to reach the targeted audience. Via weekly meetings, participation in community events/outreach, and clinical work, NSI provides unique training for emerging neuropsychologists.

Does Literacy Moderate the Relationship between Age of Migration and Cognitive Change: Results from the Washington Heights-Inwood Community Aging Project (WHICAP)

Objective

The “healthy immigrant effect” pertains to findings that Hispanics/Latinos born outside of the US tend to be physically and emotionally healthier than individuals born in the US. However, immigrant Latino groups residing in the US have higher incidences of dementia (Tang et al., 2001). Sex/gender and years of education have been found to moderate the relationship between age of migration and cognitive functioning among immigrants born in Mexico (Garcia et al., 2017; Hill et al., 2012). While years of education has been the focus of many studies, literacy (ability to read/write) has been less frequently explored as a moderator of age of migration and cognitive change. We investigated the effect of age of migration on cognitive trajectory in a diverse Latino population and explored whether literacy influences the association between age of immigration and cognitive change. We hypothesize that literacy (ability to read/write) will buffer the effects of age of migration on cognitive (memory, language, motor speed, visuospatial) trajectory.

Participants and Method

Age at baseline, English fluency, country of birth, sex/gender, and years of education were included as time-invariant covariates and literacy was tested as a moderator via multiple group modeling.

Results

Results show that age of migration is marginally and inversely associated with baseline cognitive performance (p &lt; .01). Thus, individuals who immigrated at an older age had lower baseline cognitive scores than their counterparts. Age of migration was not associated with cognitive change. Independent of covariates, literacy did not buffer the negative effects of later age at migration on cognitive function.

Conclusions

Results suggest that literacy confers a small advantage in premorbid cognition, but does not protect against cognitive decline over time. These findings also suggest that adults who immigrate at an older age present with lower cognitive scores at baseline, but do not experience faster rates of cognitive change.

References

Tang, M. X., Cross, P., Andrews, H., Jacobs, D. M., Small, S., Bell, K., ... & Mayeux, R. (2001). Incidence of AD in African-Americans, Caribbean Hispanics, and Caucasians in northern Manhattan. Neurology, 56, 49-56. Garcia, M. A., Reyes, A. M., Downer, B., Saenz, J. L., Samper-Ternent, R. A., & Raji, M. (2018). Age of migration and the incidence of cognitive impairment: A cohort study of elder Mexican-Americans. Innovation in aging, 1, igx037. https://doi.org/10.1093/geroni/igx037. Hill, T. D., Angel, J. L., Balistreri, K. S., & Herrera, A. P. (2012). Immigrant Status and Cognitive Functioning in Late Life: An Examination of Gender Variations in the Healthy Immigrant Effect. Social Science & Medicine (1982), 75, 2076–2084. http://doi.org/10.1016/j.socscimed.2012.04.005.

The Role of Quality of Education in Neurocognitive Functioning in a Diverse Sample with Chronic Opioid Use Disorder

Objective

Literacy is a proxy for quality of education (QoE) and mediates ethnicity-related differences in neurocognitive (NC) performance in some populations (Manly et al., 2002; Rivera Mindt et al., 2008). However, it is unknown whether this relationship exists in the context of chronic opioid use disorder (OUD). This study examined the role of ethnicity, QoE, opioid use severity, and depression in predicting NC performance in a diverse sample of persons with OUD.

Participants and Method

This cross-sectional study included 74 adults with OUD (Age M = 40.3 [SD = 10.5]; Education M = 11.3 [2.5]; 24% female; 68% Latinx and 32% Non-Latinx White [NLW]). All participants completed comprehensive NC testing and psychiatric/substance use questionnaires. Variables included ethnicity (Latinx vs. Non-Latinx White), years of education, QoE (Wide Range Achievement Test, Third Edition; WRAT-3 Reading Standard Scores), opioid use severity (high vs. low OAT dose), current depression (Beck Depression Inventory, Second Edition; BDI-II Total Score), and demographically-corrected NC T-scores were computed and used for average domain T-scores (e.g., learning, memory, verbal fluency, executive function). Bivariate and ANCOVA analyses were used to compare ethnic groups.

Results

There were no significant group differences on opioid use severity or current depression (p’s &gt; .05). However, compared to the NLW group, the Latinx group had lower years of education (M = 10.9 [SD = 1.7] vs. M = 12.2 [SD = 3.5]; t[72)] = 2.1, p &lt; .05), QoE (M = 83.1 [SD = 13.6] vs. M = 94.8 [SD = 9.4]; t[72] = 3.8, p &lt; .001), executive functioning (M = 42.0 [SD = 6.5] vs. M = 45.8 [SD = 8.5]; t[72) = 2.1, p &lt; .05), and learning (M = 32.2 [SD = 8.2] vs. M = 37.8 [SD = 8.7]; t[72)] = 2.7, p &lt; .05), with medium to large effect sizes (Cohen’s d &gt; .50). The overall effect of ethnicity became non-significant for executive functioning after accounting for QoE (F[2,70] = 10.0, p = .002) and years of education (F[2,70)] = 16.8, p &lt; .001).

Conclusions

The current study found that accounting for years of education and QoE attenuates some differences in NC performance between Latinx and Non-Latinx participants.

References

Manly, J. J., Jacobs, D. M., Touradji, P., Small, S. A., & Stern, Y. (2002). Reading level attenuates differences in neuropsychological test performance between African American and White elders. Journal of the International Neuropsychological Society, 8(3), 341-348. Mindt, M. R., Arentoft, A., Germano, K. K., D’Aquila, E., Scheiner, D., Pizzirusso, M., ... & Gollan, T. H. (2008). Neuropsychological, cognitive, and theoretical considerations for evaluation of bilingual individuals. Neuropsychology review, 18(3), 255-268.

MOLECULAR TYPING OF MYCOBACTERIUM KANSASII — A GLOBAL PERSPECTIVE

.

Analysis of Mycobacterium tuberculosis Genotypic Lineage Distribution in Chile and Neighboring Countries

Tuberculosis (TB), caused by the pathogen Mycobacterium tuberculosis (MTB), remains a disease of high importance to global public health. Studies into the population structure of MTB have become vital to monitoring possible outbreaks and also to develop strategies regarding disease control. Although Chile has a low incidence of MTB, the current rates of migration have the potential to change this scenario. We collected and analyzed a total of 458 M. tuberculosis isolates (1 isolate per patient) originating from all 15 regions of Chile. The isolates were genotyped using the spoligotyping method and the data obtained were analyzed and compared with the SITVIT2 database. A total of 169 different patterns were identified, of which, 119 patterns (408 strains) corresponded to Spoligotype International Types (SITs) and 50 patterns corresponded to orphan strains. The most abundantly represented SITs/lineages were: SIT53/T1 (11.57%), SIT33/LAM3 (9.6%), SIT42/LAM9 (9.39%), SIT50/H3 (5.9%), SIT37/T3 (5%); analysis of the spoligotyping minimum spanning tree as well as spoligoforest were suggestive of a recent expansion of SIT42, SIT50 and SIT37; all of which potentially evolved from SIT53. The most abundantly represented lineages were LAM (40.6%), T (34.1%) and Haarlem (13.5%). LAM was more prevalent in the Santiago (43.6%) and Concepción (44.1%) isolates, rather than the Iquique (29.4%) strains. The proportion of X lineage was appreciably higher in Iquique and Concepción (11.7% in both) as compared to Santiago (1.6%). Global analysis of MTB lineage distribution in Chile versus neighboring countries showed that evolutionary recent lineages (LAM, T and Haarlem) accounted together for 88.2% of isolates in Chile, a pattern which mirrored MTB lineage distribution in neighboring countries (n = 7378 isolates recorded in SITVIT2 database for Peru, Brazil, Paraguay, and Argentina; and published studies), highlighting epidemiological advantage of Euro-American lineages in this region. Finally, we also observed exclusive emergence of patterns SIT4014/X1 and SIT4015 (unknown lineage signature) that have hitherto been found exclusively in Chile, indicating that conditions specific to Chile, along with the unique genetic makeup of the Chilean population, might have allowed for a possible co-evolution leading to the success of these emerging genotypes.

Prognostic significance of thymidylate synthase polymorphisms in rectal cancer patients treated with neoadjuvant chemoradiotherapy

AIM

There is a lack of prognostic factors of preoperative chemoradiation for locally advanced rectal cancer. Thymidylate synthase (TS) is the most important target of 5-fluorouracil; three main genetic polymorphisms of TS have been described. We analysed the prognostic value of these in patients with locally advanced rectal cancer treated with fluoropyrimidine-based chemoradiation.

METHOD

Ninety-nine patients treated between November 2001 and March 2009 were included. All were treated by radiotherapy (5040 cGy) and concomitant fluoropyrimidine-based chemotherapy. Three polymorphisms were analysed: (i) a double (2R) or triple (3R) repeat of a 28 base pair (bp) tandem sequence upstream of the ATG codon initiation site in the 5'-terminal regulatory region, (ii) a functional G > C single nucleotide polymorphism present in the second repeat of the 3R alleles and (iii) a 6 bp deletion at nucleotide 1494 in the 3'-untranslated region. DNA was extracted from paraffin-embedded core biopsies taken from the tumour and the genotype was analysed using polymerase chain reaction restriction fragment length polymorphism.

RESULTS

The 6 bp polymorphism was significantly associated with disease-free survival (+ 6 bp/+ 6 bp vs-6 bp/-6 bp, P = 0.032 logistic regression). No differences were found in disease-free survival according to the other polymorphisms studied. No relationship was observed between the different TS genotypes and pathological regression.

CONCLUSION

The study suggests that the TS 6 bp polymorphism may be a predictor of disease-free survival in patients with locally advanced rectal cancer treated with fluoropyrimidine-based chemoradiation.

Rifampicin-resistant Mycobacterium tuberculosis: susceptibility to isoniazid and other anti-tuberculosis drugs

Based on data from 14 Supranational Tuberculosis (TB) Reference Laboratories worldwide, the proportion of rifampicin (RMP) resistant isolates that were isoniazid (INH) susceptible by phenotypic drug susceptibility testing varied widely (0.5-11.6%). RMP-resistant isolates that were INH-susceptible had significantly lower rates of resistance to other first- and second-line anti-tuberculosis drugs (except rifabutin) compared to multidrug-resistant isolates. RMP resistance is not always a good proxy for a presumptive diagnosis of multidrug-resistant TB, which has implications for use of molecular assays that identify only RMP resistance-associated DNA mutations.

[Morbidity and mortality in a series of patients suffering from intraperitoneal neoplasia treated with peritoneal cytoreduction and hyperthermic intraperitoneal chemotherapy at the Fundación Santa Fe de Bogotá Teaching Hospital (ONCOLGroup--ATIA study)]

BACKGROUND

The procedure of radical peritonectomy followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is considered the standard treatment for peritoneal cancers.

AIMS

To evaluate various outcomes in a cohort of patients with peritoneal tumors treated with HIPEC.

METHODS

Twenty-four patients consecutively treated with radical peritonectomy plus HIPEC within the time frame of November 2007 to July 2010 were enrolled; 15 (62%) had tumors of appendicular origin, 4 (16.7%) had primary peritoneal tumors, 2 had ovarian carcinomas and there was one case of colon cancer, one carcinosarcoma and one hemangioendothelioma. Mean age was 53 years (range: 26-68) and median follow-up was 14.2 months (range: 1-32). Demographic data, histology, peritoneal cancer index (PCI), surgical procedure characteristics, recurrence-free survival (RFS), and overall survival (OS) were all evaluated. Short-term morbidity and mortality were also determined.

RESULTS

Complete cytoreduction was achieved in 18 patients (75%). Mean PCI was 15 (<10: 41% and >10: 58%), and the median (range) for surgery duration, length of stay in the Intensive Care Unit, parenteral nutritional support, and hospital stay were 12,5 (7-20) hours, 11,4 (2-74) days, 13,8 (12-65) days, and 29,1 (10-90) days, respectively. One patient (4%) died 6 months after the procedure, due to multiple associated complications. Considerable morbidity was seen in 52% of cases, including thromboembolic events (41%), catheter-related bacteremia (29%), fistulas (29%), and nephrotoxicity (25%). Six patients (25%) recurred after a median of 21 months of RFS.

CONCLUSIONS

Cytoreductive surgery plus HIPEC in well-selected patients presenting with tumors that affect the peritoneum is a procedure that can be carried out in Colombia with an adequate safety and effectiveness profile. Mortality was similar to that reported in the international literature.

[Detection of genes associated with drug resistance in Mycobacterium tuberculosis strains isolated in Chile]

BACKGROUND

The incidence of acquired resistance to antituberculous drugs of Mycobacterium tuberculosis in Chile is approximately 23%.

AIM

To analyze the mutations associated with drug resistance in drug resistant strains of Mycobacterium tuberculosis.

MATERIAL AND METHODS

In 28 drug resistant Mycobacterium tuberculosis strains isolated in Chile, genes leading to drug resistance were studied. DNA was amplified by polymerase chain reaction (PCR) and sequencing was carried out using the ABI PRISM big dye terminator cycle sequencing ready reaction kit.

RESULTS

In rifampicin-resistant strains, the mutations in rpoβ gene were in the codons S531W/L (56%), D516Y (16%) and D516V (16%). The predominant mutation in katG gene was in the codon S315L (73%) in isoniazid-resistant strains. The mutation S95T was found in the 71% of ciprofloxacin resistant strains. Only one ethambutol resistant strain had the M306I mutation. Three unreported mutations in katG were identified.

CONCLUSIONS

Drug resistance associated mutations of Mycobacterium tuberculosis isolated in Chile were similar to those reported abroad.

Polymorphisms of thymidylate synthase as prognostic factor in rectal cancer

433

Background: Neoadjuvant fluoropyrimidine-based chemotherapy (ChT) plus radiotherapy (Rt) is a standard approach for locally advanced rectal cancer. Polymorphisms of thymidylate synthase (TS), the target for fluoropyrimidines, are recognized prognostic factors in colon cancer. The aim of this study was to evaluate the prognostic value of the polymorphisms of TS in rectal cancer after neoadjuvant ChT plus Rt.

Methods: We studied one-hundred consecutive patients with stage II/III rectal cancer between November 2001 and March 2009. Patients underwent surgery 6-8 weeks after neoadjuvant Rt (5,040 cGy) plus fluoropyrimidine-based ChT. DNA was extracted from paraffin embedded biopsies. TS1494del6 and 5′-28bp repeat +G/C SNP polymorphisms were determined.

Results: Sixty-seven percent were men and median age was 67 years. ypT stage was: T0 9%, T1 2%, T2 27%, T3 60% and T4 2%; 32% had locoregional adenopathies. The median follow-up was 45 months and relapse occurred in 20% of patients. Polimorphisms could be determined in 98% of pt: -6bp/-6bp 10%, - 6bp/+6bp 39%, +6bp/+6bp 51% and 2R/2R 72%, 2R/3R 21%, 3R/3R 6%. The grade of pathological tumour regression was not associated with polymorphisms. Relapses occurred in 40% of patients -6bp/-6bp, 22% of patients -6bp/+6bp and 21% of patients +6bp/+6bp. The difference in disease- free survival (DFS) between the first and the third groups was stadistically significative (p=0.049). No relation between 5′-28bp repeat +G/C SNP polymorphism and DFS was found.

Conclusions: Our data suggest that the TS1494del6 polimorphism may be an important prognosis factor in rectal cancer receiving neoadjuvant chemoradiotherapy.

No significant financial relationships to disclose.

Pathologic response assessed by Mandard grade is a better prognostic factor than down staging for disease-free survival after preoperative radiochemotherapy for advanced rectal cancer

OBJECTIVE

The reduction in tumour stage induced by full course radiotherapy plus chemotherapy is apparent from histological changes. The purpose of this study was to determine the rate of complete pathological response and to evaluate the prognostic value for disease free survival (DFS) and disease specific survival (DSS) of the response. The relation between pretreatment variables (age, gender, stage, tumour height and [carcinoembryogenic antigen (CEA)] and postsurgical variables was compared to the pathological response.

METHOD

A total of 119 patients with stage II or III rectal cancer underwent surgery 6 weeks after neoadjuvant treatment. Group A included patients with a complete or good pathological response (Mandard grade I-II) and group B patients with a poor response (Mandard grade III-IV-V). The pretreatment endo-rectal ultrasound scan stage was compared with histopathology stage of the resected specimen. DFS and DSS were compared using the log-rank test.

RESULTS

All 119 patients (mean age 67.9 years, 83 males) underwent resection. The tumour was located in the upper, middle and lower third of the rectum in 11, 51 and 57 patients. 88 patients had a low anterior resection, 28 patients abdomino-perineal resection and three a Hartmann's operation. There was no postoperative death. The circumferential margin (CM) was involved in 10%. A complete pathological response was observed in 17 (14.2%) patients. Thirty-six (30.2%) patients had a group A and 83 a group B response. Group A showed DFS to be significantly higher than group B (log rank: P = 0.007). The DSS rate was not significantly different between the two groups (log rank P = 0.113). Down-staging was not related with DFS. No relation was found between pretreatment variables and response. A good pathological response was related to a lower rate of permanent colostomy but not with CM involvement or the number of lymph nodes.

CONCLUSION

Tumour regression of grades I or II was a good indicator of DFS in locally advanced rectal cancer, treated by neoadjuvant chemotherapy and radiotherapy. Patients with a high regression grade were associated with a lower incidence of definitive stoma formation. The regression grade was shown to be a better prognostic factor than down-staging.