Prevalence and Predictors of Sexual Dysfunction (SD) after Treatment of Localized Rectal and Anal Cancer (LRAC)

PURPOSE/OBJECTIVE(S)

SD is possible after treatment of LRAC and is associated with distress and impaired quality of life. We report the prevalence of SD in our LRAC patients treated with curative intent. We also evaluate patient/treatment-related factors associated with SD.

MATERIALS/METHODS

LRAC patients from 2010-2022 were identified. Consented patients were surveyed and patient/treatment factors were collated from medical records. Sexual function (SF) was measured using the Female Sexual Function Index (FSFI) and the International Index of Erectile Function (IIEF). The impact of disease/treatment on SF since treatment was measured using the SF Questionnaire Medical Impact Scale (SFQ-MIS). FSFI ≤ 19.2 and IIEF ≤ 32.2 were considered SD based on the mean scores of SD patients in the primary literature. SFQ-MIS ≥ 15.5 was used to dichotomize responses into "at least some impact" versus "at least no impact." Spearman rank correlations examined correlations between FSFI/IIEF and factors. Comparisons involving componential domains and factors were based on a two-sided Mann-Whitney test. RT dose, surgery, the extent of lymphadenectomy, T stage, and time since treatment were factors assessed in all patients. In females, dilator use during RT, tumor distance (TD) from the anterior vaginal wall and whole vagina, and V25Gy, V45Gy, and mean dose to the anterior vaginal wall and whole vagina were other factors assessed. In males, TD from the neurovascular bundle (NVB), V25Gy, V45Gy, and mean dose to NVB was used.

RESULTS

Forty-five patients (13.5% response rate) completed study surveys (62% males; 80% white; 71% rectal cancer patients). The median age and time since treatment were 63 and 4 yrs. respectively. RT doses ranged from 25 - 54Gy. The overall prevalence of SD was 58% (71% in females; 50% in males). The proportion of patients who reported at least some SF impact was 56% (53% in females; 57% in males). There was a marginal association between higher total IIEF and receipt of surgery (p = 0.059). A correlation of 0.44 was seen between total IIEF and TD from upper NVB-the strongest among all comparisons. In the domains of IIEF, statistically significant associations were found between intercourse satisfaction (ISAT) and TD from upper NVB (p = 0.004), overall satisfaction (OSAT) and TD from lower NVB (p = 0.040), and ISAT and T stage (p = 0.047). There were marginal associations between TD from upper NVB and OSAT (p = 0.052), orgasm (p = 0.063), and erectile dysfunction (p = 0.097). There was a marginal association between V25Gy to the anterior vaginal wall and pain during penetrative sex (p = 0.095). No other association with FSFI or its domains was significant.

CONCLUSION

SD is prevalent in a large majority of patients studied (58%). In males, higher TD from NVB was associated with better overall SF, better intercourse, and overall satisfaction. While a higher proportion of females had SD, no significant associations were found in females likely due to their small sample size.

The relationships among knowledge, self-efficacy, preparedness, decisional conflict, and decisions to participate in a cancer clinical trial

BACKGROUND

Cancer clinical trials (CCTs) are important tools in the development of improved cancer therapies; yet, participation is low. Key psychosocial barriers exist that appear to impact a patient's decision to participate. Little is known about the relationship among knowledge, self-efficacy, preparation, decisional conflict, and patient decisions to take part in CCTs.

OBJECTIVE

The purpose of this study was to determine if preparation for consideration of a CCT as a treatment option mediates the relationship between knowledge, self-efficacy, and decisional conflict. We also explored whether lower levels of decisional conflict are associated with greater likelihood of CCT enrollment.

METHOD

In a pre-post test intervention study, cancer patients (N = 105) were recruited before their initial consultation with a medical oncologist. A brief educational intervention was provided for all patients. Patient self-report survey responses assessed knowledge, self-efficacy, preparation for clinical trial participation, decisional conflict, and clinical trial participation.

RESULTS

Preparation was found to mediate the relationship between self-efficacy and decisional conflict (p = 0.003 for a test of the indirect mediational pathway for the decisional conflict total score). Preparation had a more limited role in mediating the effect of knowledge on decisional conflict. Further, preliminary evidence indicated that reduced decisional conflict was associated with increased clinical trial enrollment (p = 0.049).

CONCLUSIONS

When patients feel greater CCT self-efficacy and have more knowledge, they feel more prepared to make a CCT decision. Reduced decisional conflict, in turn, is associated with the decision to enroll in a clinical trial. Our results suggest that preparation for decision-making should be a target of future interventions to improve participation in CCTs.

Extremely high phenylalanine levels in a newborn on parenteral nutrition: phenylketonuria in the neonatal intensive care unit

A 1890-g newborn on total parenteral nutrition (TPN) had phenylalanine levels reaching 4164 μM indicating phenylketonuria (PKU). Review of 64 PKU cases from the California Newborn Screening Program disclosed another newborn diagnosed while on TPN. Phenylalanine levels rose five times faster with TPN, as estimated from rates in these infants. Thus, TPN use is associated with very high phenylalanine levels in newborns with PKU. When starting TPN soon after birth (for example, on day 1), early detection of PKU-by newborn screening 12 to 24 h after infusions are begun-should be helpful in limiting exposures to toxic levels of phenylalanine.

Abstract P3-08-03: Defects in BRCA1 Contribute to Global Differential Allele-Specific Expression

Differential allele-specific expression (DASE) has been shown to contribute to phenotypic variability in humans and more recently to the pathogenesis of cancer. DASE is associated with X-chromosome inactivation and genomic imprinting and is relatively common among non-imprinted autosomal genes. The DASE phenotype can also be transmitted by Mendelian inheritance. We have previously reported that nonsense-mediated mRNA decay (NMD) of mutant BRCA1 as well as other epigenetic mechanisms can lead to DASE of BRCA1 and enhanced susceptibility to breast cancer. BRCA1 has been implicated in many cellular processes including DNA repair, cell-cycle-checkpoint control, protein ubiquitination, and chromatin remodeling. Importantly, cells carrying a deleterious BRCA1 mutation exhibit increased genome instability, therefore, we hypothesize that defects in BRCA1 lead not only to DASE of itself, but increase genome-wide DASE and thus contribute to increased breast cancer susceptibility. To test this hypothesis, we employed a genome-wide ASE assay (Illumina Human Omni1-Quad BeadChip) using primary mammary epithelial cells [3 BRCA1 wild-type vs. 3 BRCA1 mutant carrying (2800delAA, 4154delA and R1751X)]. As shown in Table 1, cells carrying a BRCA1 mutation had significantly more DASE events as compared to wild-type cell (P<10-7). In addition, we identified 351 genes demonstrating DASE that were unique to the BRCA1 mutant cells. The cellular functions of these genes are wideranging, including DNA repair, cell cycle control, lipid metabolism and protein degradation. In summary, this study provides the first evidence that mutant BRCA1 can lead to global DASE, which in turn may contribute to the development of breast cancer in mutation carriers. This work was supported in part by the Eileen Stein-Jacoby Fund and a grant from the Congressionally Directed Medical Research Programs, Department of Defense, W81XWH-08-1-0361 (XC).

Table 1. BRCA1 mutations increase the global DASE in PMECs

t; A DASE event is defined as that the Log-ratio of allele-specific expression level of one gene is more than 1 or less than -1, i.e. the expression level from one allele is at least 50% less than the level of another allele

Circadian and light regulation of oxytocin and parvalbumin protein levels in the ciliated ependymal layer of the third ventricle in the C57 mouse

The walls of the third ventricle have been proposed to serve as a bidirectional conduit for exchanges between the neural parenchyma and the cerebrospinal fluid. In immunohistochemical studies of mice, we observed that light exposure and circadian phase affected peptide staining surrounding the third ventricle at the level of the suprachiasmatic nuclei. Under high magnification, we observed robust staining for the neurohormone oxytocin and the calcium-binding protein parvalbumin associated with cilia extending into the third ventricle from the surrounding ventricular wall; no similar staining was observed for vasopressin or calbindin. Retinal illumination had opposite effects on levels of parvalbumin and oxytocin in the cilia: light exposure during late subjective night increased oxytocin staining, but decreased parvalbumin staining in the cilia. Preventing cellular transport with colchicine eliminated immunohistochemical staining for oxytocin in the cilia. There was also a significant daily rhythm of oxytocin immunostaining in the third ventricle wall, and in magnocellular neurons in the anterior hypothalamus. The results suggest that environmental lighting and circadian rhythms regulate levels of oxytocin in the cerebrospinal fluid, possibly by regulating movement of oxytocin through the third ventricle wall.