Elizabeth Dennett

The incidence of metastasis from cutaneous squamous cell carcinoma and the impact of its risk factors.

Cutaneous squamous cell carcinoma (cSCC), the most common cancer capable of metastasis, has variable reported metastatic rates and the impact of individual risk factors for metastasis is unknown.

Survival disparities in Indigenous and non-Indigenous New Zealanders with colon cancer: the role of patient comorbidity, treatment and health service factors

Background Ethnic disparities in cancer survival have been documented in many populations and cancer types. The causes of these inequalities are not well understood but may include disease and patient characteristics, treatment differences and health service factors. Survival was compared in a cohort of Maori (Indigenous) and non-Maori New Zealanders with colon cancer, and the contribution of demographics, disease characteristics, patient comorbidity, treatment and healthcare factors to survival disparities was assessed. Methods Maori patients diagnosed as having colon cancer between 1996 and 2003 were identified from the New Zealand Cancer Registry and compared with a randomly selected sample of non-Maori patients. Clinical and outcome data were obtained from medical records, pathology reports and the national mortality database. Cancer-specific survival was examined using Kaplan–Meier survival curves and Cox hazards modelling with multivariable adjustment. Results 301 Maori and 328 non-Maori patients with colon cancer were compared. Maori had a significantly poorer cancer survival than non-Maori (hazard ratio (HR)=1.33, 95% CI 1.03 to 1.71) that was not explained by demographic or disease characteristics. The most important factors contributing to poorer survival in Maori were patient comorbidity and markers of healthcare access, each of which accounted for around a third of the survival disparity. The final model accounted for almost all the survival disparity between Maori and non-Maori patients (HR=1.07, 95% CI 0.77 to 1.47). Conclusion Higher patient comorbidity and poorer access and quality of cancer care are both important explanations for worse survival in Maori compared with non-Maori New Zealanders with colon cancer.

The effect of comorbidity on the use of adjuvant chemotherapy and survival from colon cancer: a retrospective cohort study

BackgroundComorbidity has a well documented detrimental effect on cancer survival. However it is difficult to disentangle the direct effects of comorbidity on survival from indirect effects via the influence of comorbidity on treatment choice. This study aimed to assess the impact of comorbidity on colon cancer patient survival, the effect of comorbidity on treatment choices for these patients, and the impact of this on survival among those with comorbidity.MethodsThis retrospective cohort study reviewed 589 New Zealanders diagnosed with colon cancer in 1996–2003, followed until the end of 2005. Clinical and outcome data were obtained from clinical records and the national mortality database. Cox proportional hazards and logistic regression models were used to assess the impact of comorbidity on cancer specific and all-cause survival, the effect of comorbidity on chemotherapy recommendations for stage III patients, and the impact of this on survival among those with comorbidity.ResultsAfter adjusting for age, sex, ethnicity, area deprivation, smoking, stage, grade and site of disease, higher Charlson comorbidity score was associated with poorer all-cause survival (HR = 2.63 95%CI:1.82–3.81 for Charlson score ≥ 3 compared with 0). Comorbidity count and several individual conditions were significantly related to poorer all-cause survival. A similar, but less marked effect was seen for cancer specific survival. Among patients with stage III colon cancer, those with a Charlson score ≥ 3 compared with 0 were less likely to be offered chemotherapy (19% compared with 84%) despite such therapy being associated with around a 60% reduction in excess mortality for both all-cause and cancer specific survival in these patients.ConclusionComorbidity impacts on colon cancer survival thorough both physiological burden of disease and its impact on treatment choices. Some patients with comorbidity may forego chemotherapy unnecessarily, increasing avoidable cancer mortality.

Ethnicity and management of colon cancer in New Zealand: do indigenous patients get a worse deal?

Racial and ethnic inequalities in colon cancer treatment have been reported in the United States but not elsewhere. The authors of this report compared cancer treatment in a nationally representative cohort of Maori (indigenous) and non‐Maori New Zealanders with colon cancer.

Local Invasion of the Bladder With Colorectal Cancers: Surgical Management and Patterns of Local Recurrence

PURPOSE: Colorectal cancers may be adherent to the urinary bladder. To achieve oncologic clearance of the cancer, en bloc bladder resection should be performed. This study describes the multicenter experiences of en bloc bladder resection for colorectal cancer in the major New Zealand public hospitals. METHODS: A retrospective database of patients undergoing surgery for colorectal cancer adherent to the bladder between 1984 and 1999 was constructed. Data was analyzed for age, gender, disease stage, and outcome (local recurrence and survival). RESULTS: Fifty-three patients were identified: International Union Against Cancer and American Joint Committee on Cancer Stage 1 = 0; Stage 2 = 23; Stage 3 = 22; Stage 4 = 6; unknown = 2. Forty-five had en bloc partial cystectomy performed, four en bloc total cystectomy, and four had the adhesions disrupted and no bladder resection. The most common site of the primary colorectal cancer is sigmoid colon, with local invasion into the dome of the bladder. All patients who did not have en bloc resection developed local recurrence and died from their disease. Mean follow-up was 62 months. The extent of bladder resection did not seem important in determining local recurrence. CONCLUSIONS: En bloc resection of the urinary bladder should be performed if the patient is to be offered an optimal oncologic resection for adherent colorectal cancer. The decision to perform total rather than partial cystectomy should be based on the anatomic location of the tumor. Because the sigmoid is usually the primary site, most patients will not have received preoperative radiation. Therefore, postoperative radiotherapy may reduce local recurrence in these patients.

Prognostic significance of occult metastases in colon cancer.

AbstractPURPOSE: The purpose of this study was to determine the prognostic significance of occult lymph node metastases in colon cancer detected by cytokeratin 20 reverse transcription polymerase chain reaction. METHODS: Two hundred patients undergoing elective colonic resections were enrolled in the study. Lymph nodes from resected specimens were dissected fresh and assessed by both reverse transcription polymerase chain reaction and histopathology. Follow-up was undertaken for up to five years, and the major end point of death was recorded. Univariate survival analysis was performed by the log-rank method and the change-in-estimate method was used to construct multivariate analysis models for the effect of cytokeratin 20 reverse transcription polymerase chain reaction lymph node status on overall survival. RESULTS: A total of 2,317 lymph nodes from 200 patients were assessed by both histopathology and cytokeratin 20 reverse transcription polymerase chain reaction. Forty-eight of 141 (34 percent) histologically lymph node–negative patients had evidence of occult metastases by cytokeratin 20 reverse transcription polymerase chain reaction. An interim analysis was performed at a median of 42 (range, 23–75) months. Cytokeratin 20 reverse transcription polymerase chain reaction lymph node status was a highly significant predictor of overall survival (P < 0.0001) on univariate analysis. In addition, the number of reverse transcription polymerase chain reaction–positive lymph nodes was a significant predictor of survival in the histologically lymph node–negative group (P < 0.0001) on univariate analysis. On multivariate analysis cytokeratin 20 reverse transcription polymerase chain reaction lymph node status had independent prognostic significance for overall survival (P = 0.021; hazard ratio = 2.7) and the number of cytokeratin 20 reverse transcription polymerase chain reaction–positive lymph nodes was a significant predictor of overall survival in the histologically lymph node–negative group (P = 0.005; hazard ratio = 1.1–11.1). CONCLUSION: Cytokeratin 20 reverse transcription polymerase chain reaction has potential as a clinically useful marker for staging colorectal cancer. Further follow-up is required, but if the current trends continue, a study of the effect of adjuvant therapy in patients with occult metastases detected by cytokeratin 20 reverse transcription polymerase chain reaction is indicated.

Changing incidence of non-melanoma skin cancer in New Zealand.

Background:  Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the commonest types of non‐melanoma skin cancer (NMSC). The incidence of NMSC has been increasing globally with Australia recording a 1.5‐fold increase over the last 17 years. The incidence of NMSC in New Zealand is currently unknown. Given that Australia and New Zealand share similar latitude, sun exposure levels, and other risk factors, it is conceivable this increase has also occurred in New Zealand. This study aimed to provide an analysis of the incidence of NMSC within the Central Region of New Zealand based on longitudinal data derived from pathology reports.

Cancer-specific administrative data–based comorbidity indices provided valid alternative to Charlson and National Cancer Institute Indices

OBJECTIVE We aimed to develop and validate administrative data-based comorbidity indices for a range of cancer types that included all relevant concomitant conditions. STUDY DESIGN AND SETTINGS Patients diagnosed with colorectal, breast, gynecological, upper gastrointestinal, or urological cancers identified from the National Cancer Registry between July 1, 2006 and June 30, 2008 for the development cohort (n=14,096) and July 1, 2008 to December 31, 2009 for the validation cohort (n=11,014) were identified. A total of 50 conditions were identified using hospital discharge data before cancer diagnosis. Five site-specific indices and a combined site index were developed, with conditions weighted according to their log hazard ratios from age- and stage-adjusted Cox regression models with noncancer death as the outcome. We compared the performance of these indices (the C3 indices) with the Charlson and National Cancer Institute (NCI) comorbidity indices. RESULTS The correlation between the Charlson and C3 index scores ranged between 0.61 and 0.78. The C3 index outperformed the Charlson and NCI indices for all sites combined, colorectal, and upper gastrointestinal cancer, performing similarly for urological, breast, and gynecological cancers. CONCLUSION The C3 indices provide a valid alternative to measuring comorbidity in cancer populations, in some cases providing a modest improvement over other indices.

The impact of splenectomy on outcome after resection for colorectal cancer: a multicenter, nested, paired cohort study.

PurposeThis study was designed to determine whether incidental splenectomy for iatrogenic injury affects long-term cancer-specific survival in patients having resection of an adenocarcinoma of the sigmoid or rectum.MethodsA retrospective case-matched review of patients undergoing surgery for colorectal cancer with incidental splenectomy between January 1, 1990 and December 31, 1999 was undertaken. Data were analysed for age, American Society of Anesthesiologists physical status, gender, disease stage, operation type, and outcome. These cases were matched with patients from the same center, of the same age and gender, with the same stage of disease and operation, who did not require a splenectomy at the time of their surgery.ResultsFifty-five patients were identified who had an iatrogenic splenectomy. Matched gender, stage, and American Society of Anesthesiologists-matched controls were identified. Follow-up from time of surgery to death or last follow-up ranged from 2 to 205 (median, 43) months. A Kaplan-Meier survival analysis using the Cox proportional hazards model to define the statistical significance found a significant difference between the groups favoring those without splenectomy (hazard ratio, 1.8; 95 percent confidence interval (CI), 1–3.3; P = 0.0399). Cancer-specific survival at five years was 70 vs. 47 percent and at ten years was 55 vs. 38 percent.DiscussionPatients with colorectal cancer who had splenectomy as a result of iatrogenic damage of the spleen while undergoing resection of the sigmoid or rectum for adenocarcinoma had a significantly worse prognosis.

Identifying important comorbidity among cancer populations using administrative data: Prevalence and impact on survival.

Our study sought to optimize the identification and investigate the impact of comorbidity in cancer patients using routinely collected hospitalization data.