A comparison of rates and predictors of hospital readmission: Outpatient versus inpatient mastectomy for breast cancer

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Background: The odds of readmission have been reported to be slightly higher with outpatient (OP) compared to inpatient (IP) mastectomy, although overall rates are low. While OP mastectomy procedures have become more common, predictors of readmission and current rates are unknown. Methods: Observational study of women 18+ years who underwent mastectomy in California from 2005-2009 from the Healthcare Cost and Utilization Project (HCUP) linked state database. Associations of readmission and post-mastectomy complications with length of stay (LOS) were assessed using Jonkheere – Terpstra test for trend. Multivariate logistic regression was used to test the association of LOS with readmission to hospital within 30 days, adjusting for patient, clinical, and hospital factors. Results: Readmission rates for OP compared to IP mastectomy was 3.3 % vs. 5.6% (p<0.0001). OP mastectomy had the highest hematoma/seroma and chemotherapy related anemia/ neutropenia readmissions (19% p=0.0112; 2.9% p=0.0009). Readmits for cardiopulmonary events were higher for the longest LOS. Multivariate analysis showed increased readmission rates by LOS, race, payer, comorbidities (all p-values <0.0001). Odds of readmission were higher with increasing LOS vs. OP (1d OR 1.13 95% CI 0.99-1.3; 2d OR 1.6 95%CI 1.4-1.8; ≥3d OR 3.0 95%CI 2.6-3.4). Increased odds of readmission was associated with African-Americans (OR 1.5 95%CI 1.2-1.9) and Whites (OR 1.4 95%CI 1.2-1.7) vs. Asians. Revisit rates were higher with Medicare (OR 1.7 95%CI 1.4-1.9) and Medicaid (OR 1.6 95%CI 1.3-1.8) compared to private insurance. The highest readmission rates were ≥ 3 comorbidities (OR 2.7 95%CI 2.2-3.2). Conclusions: In California, readmission rates increase with increasing LOS. Risks of readmission following IP mastectomy are higher compared to OP. Low readmission rates suggest appropriate selection of patients for OP mastectomy. However, subsets of patients are at higher risk of readmission. Additional studies of patients with extended LOS; racial disparities in access to services; and evaluation of payer policies are needed to improve care and decrease hospital readmissions.

Elderly patients with colon cancer have unique tumor characteristics and poor survival

BACKGROUND

The incidence of colon cancer increases with age, and colon cancer predominantly affects individuals >65 years old. However, there are limited data regarding clinical and pathologic factors, treatment characteristics, and survival of older patients with colon cancer. The objective of this study was to determine the effects of increasing age on colon cancer.

METHODS

Patients diagnosed with colon cancer between 1988 and 2006 were identified through the Los Angeles County Cancer Surveillance Program, in Southern California. Patients were stratified into 4 age groups: 18-49, 50-64, 65-79, and ≥80 years. Clinical and pathologic characteristics and disease-specific and overall survival were compared between patients from different age groups.

RESULTS

A total of 32,819 patients were assessed. Patients aged 18 to 49 and 65 to 79 years represented the smallest and largest groups, respectively. A near equal number of males and females were diagnosed with colon cancer in the 3 youngest age groups, whereas patients who were ≥80 years old were more commonly white and female. Tumor location was different between groups, and the frequency of larger tumors (>5 cm) was greatest in youngest patients (18-49 years). The oldest patients (≥80 years) were administered chemotherapy at the lowest frequency, and disease-specific and overall survival rates decreased with increasing age.

CONCLUSIONS

This investigation demonstrates that older age is associated with alterations in clinical and pathologic characteristics and decreased survival. This suggests that the phenotype of colon cancer and the efficacy of colon cancer therapies may be dependent on the age of patients.

Contralateral breast cancer: Effect of stage on survival after unilateral breast cancer

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Background: Contralateral breast cancer (CBC) is the most common malignancy among breast cancer survivors. We investigated the impact of CBC on overall survival (OS) after unilateral primary breast cancer (UPBC) in women treated with mastectomy. Methods: Using the Surveillance Epidemiology End Results registry, we identified women age 25-80 diagnosed 1998-2006 with UPBC stage 0-III, treated with mastectomy and free of CBC at 1-year landmark. Subjects were split into test and validation samples. Follow-up continued until the earliest occurrence: death, end of 2008, or age 85. Primary risk factor was incident CBC, a time-dependent variable categorized as advanced-stage (IIB-IV), early-stage (0-IIA), or none. Proportional hazards regression adjusted for primary tumor characteristics, treatment including contralateral prophylactic mastectomy (CPM), demographics, and aging. Results: Subjects (n= 109,411, age 53.7[+12.7] years at UPBC diagnosis) were followed median 51 months. Most UPBC were early stage (63%), moderately/poorly differentiated (78%), ER+PR+ (52%). Few (9.8%) women underwent CPM at primary diagnosis. Incident CBC (n=867, 0.79%) was diagnosed median 23.5 (95% CI 1.2-72) months beyond the 1-year landmark. Test and validation samples did not differ. Only CBC of stage IIB-IV increased mortality; early stage CBC had no effect on OS. Among CBC cases, advanced stage was independently associated with aggressive UPBC (more positive nodes; larger tumor; greater extension), African-American race, and shorter time from UPBC. Conclusions: Among women who undergo mastectomy +/-CPM for UPBC, few develop CBC, which impacts survival only when diagnosed at advanced stage. Efforts to improve survival after UPBC should emphasize earlier detection and prevention of advanced-stage CBC, especially in African-American women and women with more aggressive UPBC. [Table: see text]

Predictors of primary and distant site surgery in patients with stage IV colorectal cancer

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Background: Operative management of primary tumor and distant metastases in stage IV colorectal cancer is highly variable and removal of asymptomatic primary tumors in the setting of distant disease remains controversial. The purpose of our study was to describe the patterns of surgery in stage IV colorectal cancer patients in a US population-based cohort and explore patient and tumor characteristics associated with treatment selection and survival.

Methods: Stage IV colorectal cancer patients in Los Angeles County from 2000 to 2006 were identified using the LA County Cancer Surveillance Program registry. The cohort included 2,956 patients (2,211 stage IV colon and 745 stage IV rectal cancers). Cox proportional hazard models were used to estimate survival. Treatment was categorized as primary surgery, distant site surgery, or chemotherapy only. Multivariate logistic regression was used to identify patient and tumor variables associated with treatment.

Results: Greater than 65% of the stage IV colorectal cohort had primary tumor surgery of which 51% had chemotherapy. Only 4.5% had surgery to remove distant disease. Patients who had chemotherapy only and no surgery was 15%. Median survival of primary surgery, distant surgery, or chemo only was 14, 21, and 11 months. Multivariate Cox regression revealed that primary surgery and distant surgery had a decreased risk of death compared to no surgery (HR= 0.4 p<.0001, HR=0.7 p<.004). Multivariate logistic regression was used to identify predictors associated with treatment selection. Patients >65 years (p<.003); low socioeconomic status (p<0.05); and rectal tumors (p<.0001) were less likely to have surgery of the primary tumor. Female gender (p<.0001) and primary tumor surgery (p<.0001) were predictors for distant site surgery whereas age>65 years (p<.0001) had a negative association.

Conclusions: Our population-based study of stage IV colorectal cancer patients suggests that the majority of stage IV patients with distant disease have surgery, but less than 5% have surgery for distant disease. Although survival of stage IV colorectal patients is improved with surgery, increasing age, low socioeconomic status, and rectal tumors are negative predictors for undergoing surgery.