Conditional disease-free survival after surgical resection of gastrointestinal stromal tumors: a multi-institutional analysis of 502 patients

IMPORTANCE

Gastrointestinal stromal tumors (GISTs) are the most commonly diagnosed mesenchymal tumors of the gastrointestinal tract. The risk of recurrence following surgical resection of GISTs is typically reported from the date of surgery. However, disease-free survival (DFS) over time is dynamic and changes based on disease-free time already accumulated following surgery.

OBJECTIVES

To assess the comparative performance of established GIST recurrence risk prognostic scoring systems and to characterize conditional DFS following surgical resection of GISTs.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study of 502 patients who underwent surgery for a primary, nonmetastatic GIST between January 1, 1998, and December 31, 2012, at 7 major academic cancer centers in the United States and Canada.

MAIN OUTCOMES AND MEASURES

Disease-free survival of the patients was classified according to 5 prognostic scoring systems, including the National Institutes of Health criteria, modified National Institutes of Health criteria, Memorial Sloan Kettering Cancer Center GIST nomogram, and American Joint Committee on Cancer gastric and nongastric categories. The concordance index (also known as the C statistic or the area under the receiver operating curve) of established GIST recurrence risk prognostic scoring systems. Conditional DFS estimates were calculated.

RESULTS

Overall 1-year, 3-year, and 5-year DFS following resection of GISTs was 95%, 83%, and 74%, respectively. All the prognostic scoring systems had fair prognostic ability. For all tumor sites, the American Joint Committee on Cancer gastric category demonstrated the best discrimination (C = 0.79). Using conditional DFS, the probability of remaining disease free for an additional 3 years given that a patient was disease free at 1 year, 3 years, and 5 years was 82%, 89%, and 92%, respectively. Patients with the highest initial recurrence risk demonstrated the greatest increase in conditional survival as time elapsed.

CONCLUSIONS AND RELEVANCE

Conditional DFS improves over time following resection of GISTs. This is valuable information about long-term prognosis to communicate to patients who are disease free after a period following surgery.

Adherence to Guidelines for Adjuvant Imatinib Therapy for GIST: A Multi-institutional Analysis

BACKGROUND

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. Adjuvant imatinib therapy improves recurrence-free and overall survival following surgery for patients with high-risk GIST; however, the factors associated with use of adjuvant imatinib therapy are unclear, and adherence to adjuvant imatinib has not been investigated. We sought to determine the clinicopathologic predictors of therapy with adjuvant imatinib following surgical resection for GIST and to determine the utilization of adjuvant imatinib in patients who underwent surgical resection of primary GIST in 2009 or later as recommended by National Comprehensive Cancer network (NCCN) guidelines.

METHODS

A multi-institutional cohort including 171 patients who underwent surgery for primary GIST at seven high-volume cancer centers in the USA and Canada between January 2009-December 2012 was used in this study. Receipt of adjuvant imatinib therapy was ascertained, and factors associated with imatinib therapy were analyzed.

RESULTS

Following surgery for primary GIST, tumor size (<5.0 cm: ref; 5.0-9.9 cm: odds ratio (OR) 2.36, 95 % confidence interval (CI) 0.74-7.55; >10.0 cm: OR 9.15, 95 % CI 2.28-36.75; p = 0.007), mitotic rate (≤5/50 mitoses per 50 high powered field [HPF]: ref; 6-10/50 HPF: OR 24.91, 95 % CI 3.64-170.35; >10/50 HPF: OR 5.80, 95 % CI 3.64-170.35; p < 0.001), and neoadjuvant therapy (OR 9.52; 95 % CI 2.51-36.14; p = 0.001) were associated with receipt of adjuvant imatinib therapy. Overall, 75 % of patients received appropriate treatment, 23 % of patients were undertreated, and 2 % of patients were overtreated as compared to NCCN guidelines. Adjuvant imatinib therapy was administered in only 53 % of patients for which the NCCN guidelines recommended adjuvant therapy.

CONCLUSION

The clinicopathologic factors associated with use of adjuvant imatinib therapy in patients following resection of primary GIST are consistent with established risk factors for recurrence. Adjuvant imatinib therapy remains underutilized in patients with intermediate and high-risk GIST and in patients who receive neoadjuvant therapy. Barriers to adjuvant imatinib therapy in this group of patients needs to be further explored.

Variation in readmission by hospital after colorectal cancer surgery

IMPORTANCE

Hospital readmission after colorectal surgery is common, with reported 30-day readmission rates ranging from 10% to 14%. Readmission has become a major hospital quality metric, but it is unclear whether there is much difference in readmission among hospitals after appropriate risk adjustment.

OBJECTIVE

To assess the variability in risk-adjusted readmission rates among hospitals after colorectal surgery.

DESIGN, SETTING, AND PARTICIPANTS

We performed a hierarchical multivariable logistic regression analysis of observational data obtained from the Surveillance, Epidemiology, and End Results-Medicare linked database, a nationally representative cancer registry. We studied 44,822 patients who underwent colorectal resection for cancer at 1401 US hospitals from January 1, 1997, through December 31, 2002.

MAIN OUTCOMES AND MEASURES

Variation in risk-adjusted 30-day readmission among hospitals.

RESULTS

The median age of the study patients was 78 years (interquartile range [IQR], 72-83 years). The overall 30-day readmission rate was 12.3% (n = 5502). Looking at hospitals that performed at least 5 operations annually, we found marked variation in raw readmission rates, with a range of 0% to 41.2% (IQR, 9.5%-14.8%). However, after adjusting for patient characteristics, comorbidities, and operation types in a hierarchical model, no significant variability was found in readmission rates among hospitals, with a range of 11.3% to 13.2% (IQR, 12.1%-12.4%). Furthermore, the 95% CI for hospital-specific readmission overlapped the overall mean at every hospital.

CONCLUSIONS AND RELEVANCE

Little risk-adjusted variation exists in hospital readmission rates after colorectal surgery. The use of readmission rates as a high-stakes quality measure for payment adjustment or public reporting across surgical specialties should proceed cautiously and must include appropriate risk adjustment.

Surgical management of advanced gastrointestinal stromal tumors: an international multi-institutional analysis of 158 patients

BACKGROUND

Patients with advanced gastrointestinal stromal tumors (GIST) are at high risk for recurrence after surgery. The aim of this study was to characterize outcomes of advanced GIST treated with surgery from a large multi-institutional database in the tyrosine kinase inhibitor (TKI) era.

STUDY DESIGN

Patients who underwent surgery for an advanced GIST from 1998 through 2012 were identified. Demographic, clinicopathologic, perioperative, and survival data were collected and analyzed.

RESULTS

There were 87 patients with locally advanced GIST and 71 patients with recurrent/metastatic GIST. The vast majority (95%) of patients with locally advanced GIST required a multivisceral resection; most patients (87%) underwent a microscopically complete (R0) resection. Although 82% of patients had high-risk tumors according to modified NIH criteria or had recurrent/metastatic disease, only 56% of patients received adjuvant TKI therapy. Among patients with locally advanced GIST, 3-year recurrence-free survival and overall survival rates were 65% and 87%, respectively. In contrast, 3-year recurrence-free survival and overall survival rates among patients with recurrent/metastatic GIST were 49% and 82%, respectively. On multivariate analysis, predictors of worse outcomes included high mitotic rate and male sex for patients with locally advanced GIST, and age and lack of adjuvant TKI therapy were associated with adverse outcomes among patients with recurrent/metastatic GIST (all p < 0.05).

CONCLUSIONS

Resection of advanced GIST can be safely accomplished with high rates of R0 resection. Among patients with advanced GIST, TKI therapy was underused. Barriers to the use of TKI therapy in this population should be explored.

Treatment options and surveillance strategies after therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and the third leading cause of cancer death worldwide. Recurrence rates after curative intent treatment for HCC are high; 5-year disease-free survival ranges from only 19 to 81 %. There is no direct evidence to guide the optimal frequency and method of surveillance for recurrent HCC after curative intent treatment. In contrast, there is strong evidence supporting both primary screening for HCC in patients with chronic liver disease. After resection, HCC tends to recur locally, whereas the pattern after transplantation is more at extrahepatic sites. In theory, if an HCC recurrence is discovered early, more therapeutic options are available for treatment of the recurrent HCC. As such, close surveillance after curative intent therapy may have the potential to prolong survival. We herein review the available literature derived from primary surveillance of patients with cirrhosis, as well as data on postoperative surveillance of HCC patients. In aggregate, although data remain scarce, close surveillance with α-fetoprotein and cross-sectional imaging every 3-4 months for 3 years after curative intent therapy, followed by surveillance every 6-12 months thereafter, seems the most prudent approach to follow-up of patients with HCC in the postsurgical setting.

Surgical management of disappearing colorectal liver metastases

BACKGROUND

Owing to expanded surgical indications for colorectal liver metastasis (CRLM) and improved systemic therapy, hepatic surgeons are increasingly faced with the problem of disappearing (no longer visible on imaging) liver metastasis (DLM).

METHODS

A review of relevant studies was performed. Studies that reported on DLM associated with preoperative chemotherapy for CRLM were identified, and data were synthesized and tabulated. The PubMed database was searched for relevant articles published between January 2000 and December 2012.

RESULTS

A complete response on imaging does not necessarily equate with a complete clinical or pathological response. Rather, residual macroscopic disease is found in about 25-45 per cent of patients at the time of operation. Even among patients with a complete pathological response, long-term remission occurs in only 20-50 per cent of those treated with systemic therapy. A durable response of DLM is more common following the use of hepatic artery infusion therapy.

CONCLUSION

Liver resection should include all original sites of disease if possible.

Vaginal reconstruction following radical surgery for colorectal malignancies: a systematic review of the literature

INTRODUCTION

Vaginectomy is frequently indicated to ensure an adequate resection in rectal cancer. This paper reviews the success, complications, and functional results after various methods of vaginal reconstruction following resection for rectal tumors.

METHODS

A systematic review of the literature was performed by using the MEDLINE database, Embase, and the Cochrane library (1990-2010).

RESULTS

Eighteen papers were available to review. Fifty percent of all women who received a neovagina following vaginectomy returned to sexual activity postoperatively. The rectus abdominis myocutaneous (RAM) flap remains the most common method of vaginal reconstruction after surgery for colorectal cancer. Advantages include low operative morbidity, a wide arc of rotation, and ease of harvest. Alternatives to flap reconstruction of the vagina have limited indications because of higher morbidity rates.

CONCLUSIONS

Preferred techniques for vaginal reconstruction following vaginectomy with colorectal cancer resection include RAM flaps for partial posterior vaginal defects and bilateral Gracilis myocutaneous flaps for complete vaginal excisions.