P W Pisters

University of Texas MD Anderson Cancer Center, Houston, Texas, United States

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Publications (139)694.5 Total impact

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    ABSTRACT: The use of neoadjuvant therapy (NAC) for the treatment of potentially resectable pancreatic cancer remains controversial. In this study, we sought to evaluate cancer-specific endpoints in patients undergoing a NAC versus a surgery-first (SF) approach with specific emphasis on lymph node metastases.
    Annals of Surgical Oncology 10/2014; · 4.12 Impact Factor
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    ABSTRACT: To study the histological changes in non-neoplastic pancreas and the effects on pancreatic intraepithelial neoplasia (PanIN) after neoadjuvant chemoradiation therapy (NCRT) for pancreatic ductal adenocarcinoma (PDAC). We reviewed the archival H&E slides from 218 patients with PDAC who completed NCRT and pancreaticoduodenectomy. Sixty-five patients who underwent pancreaticoduodenectomy for PDAC without NCRT were used as controls. Various histological features were reviewed and correlated with NCRT and survival. The NCRT group had lower densities of PanIN2 (P = 0.004) and PanIN3 (P = 0.02) than the control group. The extent of fibrosis, the frequency of neuroma-like nerve proliferation and the frequency of islet cell aggregation were significantly higher in the NCRT group than in the control group (P < 0.05). The intensity of inflammation was less in the NCRT group than in the control group (P = 0.02). In the NCRT group, patents with moderate to severe fibrosis or grade 2 inflammation had poorer survival than those with mild fibrosis (P = 0.04) or those with grade 0 or grade 1 inflammation (P = 0.003), respectively. Non-neoplastic pancreatic tissue from patients who received NCRT had a reduced density of high-grade PanIN lesions, more pancreatic fibrosis, and higher frequencies of neuroma-like nerve proliferation and islet cell aggregation, but less inflammation, compared to tissue from those who did not receive NCRT.
    Histopathology 07/2013; · 2.86 Impact Factor
  • Journal of Oncology Practice 05/2013; 9(3):165-8.
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    ABSTRACT: Phosphatase and tensin homolog (PTEN) is a tumor suppressor in the AKT/mTOR pathway. Animal model studies have shown that loss of PTEN function is involved in the progression of pancreatic cancer. However, the prognostic significance of loss of PTEN expression in pancreatic cancer is unclear. PTEN expression was evaluated by immunohistochemistry on tissue microarrays consisting of multiple cores of 133 resected stage II pancreatic ductal adenocarcinomas. A PTEN expression score was calculated as the product of the percentage of positive tumor cells and the intensity of PTEN staining. We categorized PTEN expression for each tumor as retained (PTEN score >5) or lost (PTEN score ≤5). Thirty-four (25.6%) patients had tumors with loss of PTEN expression, and 99 (74.4%) had tumors with retained PTEN expression. Recurrence/Metastasis was observed in 88.2% (30/34) of patients whose tumors showed loss of PTEN compared with 68.7% (68/99) of patients whose tumors showed retained PTEN (P = .03). Patients whose tumors showed loss of PTEN had a shorter overall survival (median, 19.9 ± 3.6 months) than did patients whose tumors had retained PTEN (32.7 ± 5.0 months, P = .03). In a multivariate analysis, loss of PTEN expression was an independent prognostic factor for poor overall survival in patients with stage II pancreatic ductal adenocarcinoma. No significant correlations between loss of PTEN expression and other clinicopathologic parameters were observed (P > .05). Assessment of PTEN expression may be used as a prognostic marker for patients with resected pancreatic ductal adenocarcinoma.
    Human pathology 12/2012; · 3.03 Impact Factor
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    ABSTRACT: AIMS: Solid pseudopapillary neoplasm of the pancreas (SPN) is a rare low-grade malignant neoplasm. To our knowledge, SPN with prominent atypical multinucleated giant tumour cells (MNGTCs) has not yet been reported. METHODS AND RESULTS: We identified four cases of SPN with prominent atypical MNGTCs in a cohort of 62 cases of SPN (6.5%). The MNGTCs contained multiple enlarged, hyperchromatic, irregular nuclei with ample eosinophilic cytoplasm, typically present in the solid area of the tumour. The MNGTCs had an immunohistochemical profile typical of the conventional SPN and were positive for vimentin, β-catenin, CD10 and progesterone receptor, but negative for pan-cytokeratin, chromogranin, synaptophysin, trypsin, Ki-67 and CD68 in all four cases. Patients of SPN with prominent MNGTCs were older than those with conventional SPN (P = 0.01); tumours were discovered incidentally by imaging studies for an unrelated disease in all four cases, and with a female to male ratio of 1:1. The proliferation index (Ki-67) was <1% in all four cases. None of the three patients for whom information was available developed recurrence during follow-up of 2.7, 3.8 and 5.0 years. CONCLUSIONS: The presence of MNGTCs in SPN most probably represents degenerative change of the tumour cells and does not seem to affect the prognosis.
    Histopathology 09/2012; · 2.86 Impact Factor
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    ABSTRACT: Protein phosphatase 4 (PP4) has been reported to be overexpressed in breast and lung cancers. PP4 plays an important role in the regulation of centrosome maturation, DNA repair, NF-κB, and c-jun-NH(2)-kinase (JNK) signaling pathways. However, the expression and functions of PP4 in pancreatic cancer have not been studied. Experimental Design: We examined the expression of PP4 catalytic subunit (PP4C) protein in 133 patients with stage II pancreatic ductal adenocarcinoma (PDAC) and their paired benign pancreatic samples (N = 113) by immunohistochemistry. To confirm the immunohistochemical results, we measured PP4C protein and mRNA levels by Western blotting and real-time reverse transcriptase PCR. Using univariate and multivariate analysis, we correlated PP4C expression with survival and other clinicopathologic features. PP4C was overexpressed in 75 of 133 (56.4%) stage II PDAC samples, which was significantly higher than the paired benign pancreatic tissue (15%, 17 of 113). PP4C mRNA expression levels were also higher in PDAC samples than the paired benign pancreatic tissue. Overexpression of PP4C in PDAC samples was associated with higher frequencies of distant metastasis (P = 0.02) and poor disease-free and overall survivals in patients with stage II PDAC (P = 0.006 and 0.02) independent of tumor size, margin status, and lymph node status (stage). Our study showed that PP4C is overexpressed in PDAC. Overexpression of PP4C in PDAC samples is associated with poor prognosis in patients with stage II PDAC. Therefore, targeting PP4 signaling pathway may represent a new approach for the treatment of PDAC. Our study showed that PP4C is an independent prognostic factor in patients with stage II PDAC.
    Cancer Epidemiology Biomarkers &amp Prevention 06/2012; 21(8):1336-43. · 4.56 Impact Factor
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    ABSTRACT: Perineural invasion (PNI) is one of the established prognostic factors in pancreatic ductal adenocarcinoma (PDAC). However, the prognostic significance of PNI in patients with PDAC who received neoadjuvant therapy and pancreaticoduodenectomy is not clear. In this study, we performed a detailed examination of neural invasion in pancreaticoduodenectomy specimens from 212 patients with PDAC who received neoadjuvant chemoradiation (treated group) and in 60 untreated patients at our institution between January 1999 and December 2007. The frequency of PNI was higher in the untreated group (80%, 48/60) than in the treated group (58%, 123/212). For the 123 treated cases that were positive for PNI, extratumoral PNI, intratumoral PNI, intrapancreatic PNI only, extrapancreatic PNI, and intraneural invasion were identified in 86 (69.9%), 37 (30.1%), 11 (8.9%), 112 (91.1%), and 35 cases (28.5%), respectively. The presence of PNI correlated with tumor size, margin status, lymph node metastasis, pathologic tumor, and American Joint Committee on Cancer stages in the treated group. Tumor involvement of nerves >0.8 mm correlated with higher frequency of positive margin compared with tumors with PNI involving nerves ≤0.8 mm but not with other clinicopathologic parameters and survival. In the treated group, the presence of PNI or intraneural invasion correlated significantly with shorter disease-free survival and overall survival compared with no PNI or PNI only, respectively. PNI was an independent prognostic factor for both disease-free survival and overall survival in multivariate analysis. Our results showed that PNI plays an important role in the progression of PDAC and in predicting prognosis in this group of patients.
    The American journal of surgical pathology 03/2012; 36(3):409-17. · 4.06 Impact Factor
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    ABSTRACT: Lymphovascular invasion (LVI) is a prognostic factor in many types of human malignancies, including pancreatic ductal adenocarcinoma (PDAC). However, the prognostic significance of LVI in patients with PDAC who have received neoadjuvant therapy and pancreaticoduodenectomy is unclear. In this study, we analyzed LVI in 212 patients who had received neoadjuvant chemoradiation and subsequent pancreaticoduodenectomy at our institution between January 1999 and December 2007. LVI was present in 61.8% (131/212) of the patients. Of the 131 patients who were positive for LVI, 67 (31.6%) had tumor invasion into lymphovascular spaces without muscle layer (nonmuscular lymphovascular spaces), and 64 (30.2%) had tumor invasion into muscular vessels. Tumor invasion into muscular vessels correlated with higher frequencies of positive resection margin, lymph node metastasis, and locoregional/distant recurrence. Patients with tumor invasion into muscular vessels had significantly shorter disease-free survival and overall survival than did patients who had no LVI or who had tumor invasion of nonmuscular lymphovascular spaces (P<0.01). Tumor invasion into muscular vessels is an independent prognostic factor in patients with PDAC who have received neoadjuvant therapies. Our results showed that tumor invasion into muscular vessels plays an important role in the progression of PDAC and in predicting prognosis in this group of patients.
    The American journal of surgical pathology 01/2012; 36(4):552-9. · 4.06 Impact Factor
  • Peter W T Pisters, Chiara Colombo
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    ABSTRACT: Surgery is the standard of care for primary resectable gastrointestinal stromal tumors (GISTs), but half of surgically treated patients relapse. Imatinib (IM) has been shown to prolong recurrence-free survival after complete surgery and is now approved as adjuvant therapy (400  mg/day) for high-risk GIST patients. IM is well tolerated, with mild to moderate side effects observed. Whether adjuvant IM prolongs overall survival is under evaluation in two ongoing clinical trials.
    Journal of Surgical Oncology 12/2011; 104(8):896-900. · 2.64 Impact Factor
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    ABSTRACT: In patients with pancreatic ductal adenocarcinoma (PDA) who received neoadjuvant therapy and pancreatectomy, pathologic complete response (pCR) is rarely observed and the prognostic significance of pCR is not clear. In this study, we identified 11 patients with pCR (2.5%) from 442 patients with PDA who received neoadjuvant treatment and pancreatectomy from 1995 to 2010. There were 6 men and 5 women, with a median age of 61 years. Four patients had either synchronous or history of extrapancreatic cancer. Five patients received neoadjuvant chemotherapy followed by chemoradiation, and 6 received chemoradiation alone. Ten patients had pancreaticoduodenectomy, and 1 had distal pancreatectomy. Scar and chronic pancreatitis consistent with therapy effect were present in all cases (100%). Pancreatic intraepithelial neoplasia (PanIN) 3/carcinoma in situ was present in 5 cases, and PanIN1 and PanIN2 in 5 cases. However, no residual invasive carcinoma or lymph node metastasis was identified in all cases. Follow-up information was available in 10 patients. Follow-up time ranges from 6 to 194 months (median, 63 months). During the follow-up, 3 patients died of other causes, and 1 developed a second primary PDA in the tail of the pancreas at 84 months after the initial pancreaticoduodenectomy and died at 105 months after the initial diagnosis of PDA. The other 6 patients were alive with no evidence of disease. Patients with pCR had a better survival than did those who had posttherapy stage I or IIA disease (P < .001). Patients with PDA who received neoadjuvant therapy and had pCR in pancreatectomy are rare but have a better prognosis.
    Annals of diagnostic pathology 11/2011; 16(1):29-37.
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    ABSTRACT: The objective of the study was to describe patterns of care of patients with gastrointestinal stromal tumors (GISTs) in the United States in the tyrosine kinase inhibitor (TKI) era. From November 2004 through March 2009, data were collected regarding demographics, diagnostic history, treatment, relapse, and survival of 882 patients with GIST from 122 community and academic medical practices. The most common first-line treatment for the 719 patients presenting with localized GIST was surgery (87%). Use of adjuvant imatinib increased after June 2007; 47% of patients enrolled in the registry considered by the investigator to be at high risk for recurrence received adjuvant imatinib after June 2007 versus 18% before. Overall, 56% of patients received imatinib and 11% received sunitinib. The utilization of targeted therapy increased over time (45% and 0.4% of patients received imatinib and sunitinib, respectively, in 2006 versus 56% and 11%, respectively, in 2009). These are the first GIST registry data from the TKI era. The use of targeted therapy for GIST has increased in accordance with updated treatment guidelines. Diagnosis of GIST has evolved with increased use of KIT testing. The duration of targeted therapy in the adjuvant therapy setting is similar in community and academic practices.
    Annals of Oncology 04/2011; 22(11):2523-9. · 7.38 Impact Factor
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    ABSTRACT: The American College of Surgeons Oncology Group sought to confirm the efficacy of a novel interferon-based chemoradiation regimen in a multicenter phase II trial. Patients with resected (R0/R1) adenocarcinoma of the pancreatic head were treated with adjuvant interferon-alfa-2b (3 million units s.c. on days 1, 3, and 5 of each week for 5.5 weeks), cisplatin (30 mg/m(2) i.v. weekly for 6 weeks), and continuous infusion 5-fluorouracil (5-FU; 175 mg·m(2)/day for 38 days) concurrently with external-beam radiation (50.4 Gy). Chemoradiation was followed by two 6-week courses of continuous infusion 5-FU (200 mg·m(2)/day). The primary study end point was 18-month overall survival from protocol enrollment (OS18); an OS18 ≥65% was considered a positive study outcome. Eighty-nine patients were enrolled. Eighty-four patients were assessable for toxicity. The all-cause grade ≥3 toxicity rate was 95% (80 patients) during therapy. No long-term toxicity or toxicity-related deaths were noted. At 36-month median follow-up, the OS18 was 69% [95% confidence interval (CI) 60% to 80%]; the median disease-free survival and overall survival were 14.1 months (95% CI 11.0-20.1 months) and 25.4 months (95% CI 23.4-34.1 months), respectively. Notwithstanding promising multi-institutional efficacy results, further development of this regimen will require additional modifications to mitigate toxic effects.
    Annals of Oncology 02/2011; 22(2):348-54. · 7.38 Impact Factor
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    ABSTRACT: Evolving evidence suggests that, in selected patients with tumour category 1 (T1) extremity soft tissue sarcoma (ESTS), surgery alone offers satisfactory results without decreasing survival. This study assessed the effect of sarcoma treatments on survival outcomes of T1 ESTS in a population-based data set. Using the Surveillance, Epidemiology, and End Results database, 1618 patients with primary ESTS underwent limb-sparing surgery. Multivariable analysis was used to assess the impact of radiotherapy on overall survival (OS) and sarcoma-specific survival (SSS), adjusting for co-variables. Some 803 patients (49.6 per cent) underwent surgery alone for T1 ESTS. Radiotherapy in patients with low- and high-grade tumours did not result in any significant difference in OS or SSS. When stratified by grade, multivariable analysis showed that adjuvant radiotherapy was not an independent predictor of SSS (hazard ratio (HR) 1.05; P = 0.906) or OS (HR 0.89; P = 0.695) in low-grade tumours. Neither was radiotherapy a significant predictor of SSS (HR 0.87; P = 0.608) or OS (HR 0.67; P = 0.071) in high-grade tumours. This population-based appraisal validated previous evidence supporting a role for surgery alone in the treatment of T1 ESTS. Future policies should be tailored to offer patients minimal yet effective therapy, rather than maximum tolerated therapy.
    British Journal of Surgery 03/2010; 97(5):707-13. · 4.84 Impact Factor
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    ABSTRACT: Molecular markers are currently being utilized as sensitive prognosticators of cancer patient outcome. We sought to identify prognostic biomarkers for complex karyotype soft tissue sarcoma (STS). A large (n = 205) clinically annotated tissue microarray (TMA) was constructed and immunostained for several tumor-related markers. Staining was scored via an automated Ariol image analysis system; data were statistically analyzed to evaluate the correlation of clinicopathological and molecular variables with overall survival (OS) and local recurrence. Multivariable analysis identified older age [hazard ratio (HR) 1.62, P < 0.0001], nonextremity location (HR 2.95, P = 0.001), high tumor grade (HR 2.5, P = 0.02), and increased matrix metalloproteinase (MMP) 2 expression (HR 1.74, P = 0.04) as predictors for poor OS. Similarly, older age (HR 1.51, P = 0.008), nonextremity location (HR 4.09, P = 0.001), and increased MMP2 expression (HR 6.28, P = 0.006) were all found to correlate with shorter local recurrence-free interval. High nuclear p53 expression was associated with shorter STS local recurrence-free interval, with a trend toward significance. Data presented indicate that a clinically annotated TMA can be utilized to identify STS-related prognostic markers. Specifically, MMP2 and nuclear p53 should be further evaluated for their potential inclusion in complex karyotype STS staging systems.
    Annals of Oncology 10/2009; 21(5):1112-20. · 7.38 Impact Factor
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    ABSTRACT: Current American Joint Committee on Cancer retroperitoneal sarcoma (RPS) staging is not representative of patients with RPS specifically and has limited discriminative power. Our objective was to develop a RPS disease-specific nomogram capable of stratifying patients based on probability of overall survival (OS) after resection. In all, 1118 RPS patients were evaluated at our institution (1996-2006). Patients with resectable, nonmetastatic disease were selected (n = 343) and baseline, treatment and outcome variables were retrieved. A nomogram was created and its performance was evaluated by calculating its discrimination (concordance index) and calibration and by subsequent internal validation. Median follow-up and OS were 50 and 59 months, respectively. Independent predictors of OS were included in the nomogram: age (> or = 65), tumor size (> or = 15 cm), type of presentation (primary versus recurrent), multifocality, completeness of resection and histology. The concordance index was 0.73 [95% confidence interval (CI) 0.71-0.75] and the calibration was excellent, with all observed outcomes within the 95% CI of each predicted survival probability. A RPS-specific postoperative nomogram was developed. It improves RPS staging by allowing a more dynamic and robust disease-specific risk stratification. This prognostic tool can help in patient counseling and for selection of high-risk patients that may benefit from adjuvant therapies or inclusion into clinical trials.
    Annals of Oncology 08/2009; 21(2):397-402. · 7.38 Impact Factor
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    ABSTRACT: Decreased performance status, comorbidities, and disease natural history may erode enthusiasm for soft tissue sarcoma (STS) resection in elderly patients. Consequently, we evaluated the outcome of elderly patients amenable to complete surgical resection treated at a single institution. Prospectively accrued data were used to identify patients with primary STS age >or=65 years (n = 325) who underwent complete macroscopic resection at our institution (1996-2007). Univariable and multivariable analyses were performed to identify prognostic factors. Median age at presentation was 72 years; 179 patients (55.1%) had associated comorbidities with an ASA score of >or=3. Extremity was the most common site (57.1%; n = 186), undifferentiated pleomorphic sarcoma the most common histology (60.4%; n = 197); 232 (71.2%) were high grade, 222 (68.3%) were >5 cm. Thirty-day postoperative mortality was 0.9% (n = 3); overall complication rate was 30.7% (n = 100), and mean postoperative hospital stay was 9 days (range, 1-84). Estimated median survival was 96 months, 5-year disease-specific survival (DSS) was 63%. Multivariable analysis identified age >or=75 year (HR = 2.03), tumor size: 5-15 vs <5 cm (HR = 3.54), or >15 vs <5 cm (HR = 10.33), and high-grade (HR = 5.53) as significant independent adverse prognostic factors. Compared with patients aged 65-74 years, older patients had more high grade tumors (P = .04), received chemotherapy less often (P < .0001), developed different patterns of recurrence (P < .05), and exhibited a shorter median survival (70 months; P = .05). Properly selected elderly patients can safely undergo extensive STS resections. Until more effective therapies become available, surgery in the elderly is indicated and remains the best means for STS control.
    Annals of Surgical Oncology 06/2009; 16(9):2579-86. · 4.12 Impact Factor
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    ABSTRACT: Actual 5-year survival rates of 10-18% have been reported for patients with resected pancreatic adenocarcinoma (PC), but the use of multimodality therapy was uncommon in these series. We evaluated long-term survival and patterns of recurrence in patients treated for PC with contemporary staging and multimodality therapy. We analyzed 329 consecutive patients with PC evaluated between 1990 and 2002 who underwent resection. Each received a multidisciplinary evaluation and a standard operative approach. Pre- or postoperative chemotherapy and/or chemoradiation were routine. Surgical specimens of 5-year survivors were re-reviewed. A multivariate model of factors associated with long-term survival was constructed. Patients underwent pancreaticoduodenectomy (n = 302; 92%), distal (n = 20; 6%), or total pancreatectomy (n = 7; 2%). A total of 108 patients (33%) underwent vascular reconstruction, 301 patients (91%) received neoadjuvant or adjuvant therapy, 157 specimens (48%) were node positive, and margins were microscopically positive in 52 patients (16%). Median overall survival and disease-specific survival was 23.9 and 26.5 months. Eighty-eight patients (27%) survived a minimum of 5 years and had a median overall survival of 11 years. Of these, 21 (24%) experienced recurrence, 7 (8%) after 5 years. Late recurrences occurred most frequently in the lungs, the latest at 6.7 years. Multivariate analysis identified disease-negative lymph nodes (P = .02) and no prior attempt at resection (P = 0.01) as associated with 5-year survival. Our 27% actual 5-year survival rate for patients with resected PC is superior to that previously reported, and it is influenced by our emphasis on detailed staging and patient selection, a standardized operative approach, and routine use of multimodality therapy.
    Annals of Surgical Oncology 03/2009; 16(4):836-47. · 4.12 Impact Factor
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    Peter W T Pisters
    Journal of Clinical Oncology 01/2009; 27(1):6-8. · 18.04 Impact Factor
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    ABSTRACT: To evaluate the significance of multifocality on overall survival (OS) in patients with retroperitoneal sarcoma (RPS) and establish a data-derived, prognostically and therapeutically useful definition of sarcomatosis. The incidence, clinical features, and prognostic significance of multifocality in RPS is unknown. No current standardized definition for sarcomatosis is available. We conducted a retrospective analysis of 393 patients with primary or recurrent nonmetastatic RPS treated at a comprehensive cancer center between 1996 and 2006. Baseline and treatment variables were compared in patients with unifocal and multifocal disease. A multivariate model was used to evaluate the association of multifocality and OS and identify additional prognostic factors in patients with multifocal disease. The median follow-up time for all patients was 69 months; 79 patients (20%) presented with multifocal disease. The 5-year OS rate was less in the multifocal group compared with the unifocal group (31% vs. 60%, respectively; P < 0.0001). After multivariate analysis, multifocality remained an independent predictor of worse OS {hazard ratio (HR) 1.7 (95% confidence interval (CI), 1.2-2.5); P = 0.004}. Additionally, patients with more tumors had significantly worse prognosis (>7 tumors, HR 2.1 (95% CI, 1.1-3.9); P = 0.03), with a 5-year OS rate of 7%. Multifocal RPS is associated with worse OS in patients with either primary or recurrent RPS; Patients with >7 tumors had the worst prognosis. This criterion can be used to define sarcomatosis, thereby identifying patients whose survival will ultimately depend on effective systemic therapy.
    Annals of surgery 01/2009; 249(1):137-42. · 7.90 Impact Factor
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    ABSTRACT: Retroperitoneal sarcoma (RPS) American Joint Committee on Cancer (AJCC) staging applies to primary tumors only; due to specific RPS disease characteristics, staging is driven primarily by grade, stratifying patients into only two distinct prognostic subsets. The objective of this study was to help improve currently available staging for RPS by establishing a new, more robust histology-based prognostic system. A RPS database of 1,118 patients seen at our institution (1996-2006) identified 343 patients treated for resectable primary or recurrent disease; a histologic subtype-based RPS prognostic system was designed and evaluated for prognostic accuracy in comparison with the current AJCC staging system. Histology stratified patients into three groups by prognosis (P<0.0002): atypical lipomatous tumor (ALT), non-ALT liposarcoma (LPS), and "other," an improvement compared with AJCC staging which could only identify two distinct prognostic groups. In contrast to AJCC staging, this prognostic stratification was reproducible for both primary and recurrent RPS (P<0.0001). After multivariate analysis, LPS (P=0.0004) and "other" histologies (P<0.0001) were found to be independent predictors of worse survival. The concordance ratio of this model was 0.74, equivalent to that of the model using the AJCC staging system. A histology-based RPS prognostic system has two advantages over AJCC staging: it can stratify into three versus two distinct prognostic groups, and it can be used for both primary and recurrent RPS. Distinct risk stratification is critical for specific assessment of prognosis as well as decisions regarding individualized adjuvant therapies, hence the advantage of a three-tiered histology-based system applicable in both primary and recurrent RPS.
    Annals of Surgical Oncology 12/2008; 16(3):667-75. · 4.12 Impact Factor

Publication Stats

5k Citations
694.50 Total Impact Points

Institutions

  • 1992–2013
    • University of Texas MD Anderson Cancer Center
      • • Department of Surgical Oncology
      • • Division of Radiation Oncology
      Houston, Texas, United States
  • 2011
    • Virginia Mason Medical Center
      Seattle, Washington, United States
  • 2009
    • Baylor College of Medicine
      • Department of Surgery
      Houston, TX, United States
  • 2008
    • University of Louisville
      • Division of Surgical Oncology
      Louisville, KY, United States
  • 1998
    • University of Houston
      Houston, Texas, United States
  • 1990–1997
    • Memorial Sloan-Kettering Cancer Center
      • Department of Surgery
      New York City, NY, United States
  • 1993
    • State University of New York Downstate Medical Center
      • Division of Vascular Surgery
      Brooklyn, NY, United States