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Stephen P Povoski

Publications and source records attributed to Stephen P Povoski.

At least 19 recordsLinked to original sources
PubMed2007

Pilot study of rosiglitazone therapy in women with breast cancer: effects of short-term therapy on tumor tissue and serum markers.

PURPOSE: Peroxisome proliferator-activated receptor gamma (PPARgamma) is a steroid nuclear receptor that is activated by natural compounds such as specific fatty acids and synthetic drugs such as thiazolidinedione antidiabetic agents. Expressed in normal and malignant mammary epithelial cells, activation of PPARgamma is associated with antiproliferative effects on human breast cancer cells in preclinical studies. The purpose of this study was to test the hypothesis that PPARgamma ligand therapy might inhibit tumor growth and progression in human breast cancer. EXPERIMENTAL DESIGN: We conducted a pilot trial of short-term (2-6 weeks) treatment with the thiazolidinedione rosiglitazone in 38 women with early-stage (T(is)-T(2), N(0-1), M(0)) breast cancer, administered between the time of diagnostic biopsy and definitive surgery. RESULTS: Short-term treatment with rosiglitazone (8 mg/d) did not elicit significant effects on breast tumor cell proliferation using Ki67 expression as a measure of cell proliferation and surrogate marker of tumor growth and progression. In pretreatment tumors notable for nuclear expression of PPARgamma by immunohistochemistry, down-regulation of nuclear PPARgamma expression occurred following rosiglitazone administration (P = 0.005). No PPARG mutations were identified, and the incidence of P12A and H446H polymorphisms did not differ relative to U.S. controls (P = 0.5). Treatment with rosiglitazone resulted in increased serum adiponectin (P < 0.001), decreased insulin levels (P = 0.005), and increased insulin sensitivity (P = 0.004). Rosiglitazone was well tolerated without serious adverse events. CONCLUSION: Our data indicate that short-term rosiglitazone therapy in early-stage breast cancer patients leads to local and systemic effects on PPARgamma signaling that may be relevant to breast cancer.

Adult↗
PubMed2007

Diffuse optical imaging and spectroscopy for cancer.

Visible light and near infrared light interact with biological tissue by absorption and scattering. Diffuse optical imaging and spectroscopy reconstructs tissue physiologic parameters based on noninvasive measurement of tissue optical properties. This technology can be used to differentiate physiologic and molecular signatures of both malignant and benign tissues, as they relate to the area of cancer research. Major advantages are the use of non-ionizing radiation, real-time continuous data acquisition, low cost, and portability. Limitations include low spatial resolution and limited reproducibility. This paper reviews the currently available state-of-the-art technologies for diffuse optical imaging and spectroscopy and their applications in cancer research.

Biomedical Technology↗
PubMed2006

Prospective randomized clinical trial comparing intradermal, intraparenchymal, and subareolar injection routes for sentinel lymph node mapping and biopsy in breast cancer.

BACKGROUND: Multiple injection routes, including intradermal (ID), intraparenchymal (IP), and subareolar (SA), are used for 99mTc-sulfur colloid administration for sentinel lymph node (SLN) mapping and biopsy in breast cancer. The aim of this study was to compare localization by ID, IP, and SA injection routes based on preoperative lymphoscintigraphy and intraoperative identification. METHODS: Four hundred prospectively randomized breast cancers underwent SLN mapping and biopsy. RESULTS: Preoperative lymphoscintigraphy demonstrated localization to the axilla in 126/133 (95%) ID, 82/132 (62%) IP, and 96/133 (72%) SA (P < 0.001 ID vs. IP and ID vs. SA; P = 0.081 IP vs. SA), with a mean duration of preoperative lymphoscintigraphy of 139 +/- 18 minutes. Mean time to first localization when localization was demonstrated on preoperative lymphoscintigraphy was 8 +/- 14 minutes for ID, 53 +/- 49 for IP, and 22 +/- 29 for SA (P < 0.001 ID vs. IP and ID vs. SA; P = 0.003 IP vs. SA). Intraoperative identification of a SLN at the time of SLN biopsy was successful in 133/133 (100%) ID, 121/134 (90%) IP, and 126/133 (95%) SA (P < 0.001 ID vs IP; P = 0.014 ID vs. SA; P = 0.168 IP vs. SA), with a mean time from injection of 99mTc-sulfur colloid to start of SLN biopsy of 288 +/- 71 minutes. Mean intraoperative time to harvest the first SLN was 9 +/- 4 minutes for ID, 13 +/- 6 for IP, and 12 +/- 6 for SA (P < 0.001 ID vs. IP and ID vs. SA; P = 0.410 IP vs. SA). CONCLUSIONS: The ID injection route demonstrated a significantly greater frequency of localization, decreased time to first localization on preoperative lymphoscintigraphy, and decreased time to harvest the first SLN. This represents the first prospective randomized clinical trial to confirm superiority of the ID route for administration of 99mTc-sulfur colloid during SLN mapping and biopsy in breast cancer.

Breast Neoplasms↗
PubMed2006

Fibromatosis (desmoid tumor) of the breast mimicking a case of ipsilateral metachronous breast cancer.

BACKGROUND: Fibromatosis or desmoid tumor of the breast is an extremely rare entity. While it lacks a metastatic potential, it can grow aggressively in a locally infiltrating pattern. The failure to recognize this as a finite entity within the breast can lead to local recurrence after incomplete excision. CASE PRESENTATION: We report a case of a 70 year old patient with a remote history of invasive breast cancer (treated twelve years earlier by lumpectomy, axillary lymph node dissection, postoperative radiation therapy, and five years of tamoxifen) who developed fibromatosis within another quadrant of the same breast that clinically, mammographically, and sonographically mimicked that of the development of an ipsilateral metachronous breast cancer. After the initial diagnosis of fibromatosis was made on a minimally invasive ultrasound guided biopsy, it was successfully treated by wide local excision. CONCLUSION: After appropriate recognition, wide local excision can be the appropriate surgical management strategy for fibromatosis of the breast.

Journal Article↗
PubMed2006

Management of a patient with multiple recurrences of fibromatosis (desmoid tumor) of the breast involving the chest wall musculature.

BACKGROUND: Fibromatosis or desmoid tumor is a rare soft tissue tumor that lacks a metastatic potential, but is characterized by a locally aggressive and infiltrating growth pattern and a high propensity toward local recurrence if incompletely excised. CASE PRESENTATION: We report a patient with three post-surgical recurrences of fibromatosis of the breast over a seven year period. The fibromatosis was found to be involving the chest wall musculature and causing persistent and worsening pain. An aggressive operative strategy was undertaken, consisting of mastectomy with en bloc resection of the underlying chest wall musculature, ribs, and parietal pleura. CONCLUSION: Aggressive surgical management of fibromatosis of the breast with suspected chest wall involvement is appropriate to attempt to obtain a long-term durable cure.

Journal Article↗
PubMed2004

External jugular vein cutdown approach for chronic indwelling central venous access in cancer patients: A potentially useful alternative.

BACKGROUND: Cephalic vein (CV) cutdown approach for chronic indwelling central venous access device (CICVAD) placement has previously been shown to be technically feasible in 82% of cancer patients. No data are available as to the potential utilization of external jugular vein (EJV) cutdown approach in cancer patients when CV cutdown approach is not technically feasible. PATIENTS AND METHODS: One hundred and twenty consecutive cancer patients were taken to the operating room with the intention of placing a CICVAD. All patients were first subjected to attempted CV cutdown approach. If CV cutdown approach was unsuccessful and there were no contraindications to establishing central venous access in the ipsilateral neck region, an ipsilateral EJV cutdown approach was attempted. RESULTS: Ninety-five cancer patients (79%) underwent CICVAD placement via CV cutdown. Of those 25 patients in which CV cutdown was not technically feasible, 7 had a contraindication to establishing central venous access in the ipsilateral neck region and a CICVAD was placed via the ipsilateral subclavian vein percutaneous approach. Of those remaining 18 patients in which CV cutdown approach was not technically feasible, 17 (94%) underwent CICVAD placement via ipsilateral EJV cutdown approach. Combined success of the CV and EJV cutdown approaches, excluding those 7 patients with a contraindication to central venous access in the ipsilateral neck region, was greater than 99%. CONCLUSIONS: Venous cutdown approaches for CICVAD placement are viable alternatives to subclavian vein percutaneous approach in cancer patients. EJV cutdown approach appears to be a highly successful and safe alternative route when CV cutdown approach is not technically feasible and may be considered a potentially useful primary route for CICVAD placement in cancer patients.

Journal Article↗
PubMed2004

Axillary lymph node metastasis following resection of abdominal wall laparoscopic port site recurrence of gallbladder cancer.

Abdominal wall port site recurrence of gallbladder cancer is well described in the literature in patients that have undergone laparoscopic cholecystectomy with the incidental finding of a gallbladder cancer. The etiology and consequences of this type of metastatic recurrence are unclear. This report describes two cases with the unique sequelae of the interval development of nodal metastases to the axillary lymph nodes following resection of an abdominal wall laparoscopic port site recurrence of gallbladder cancer. The first case involves a patient who developed an isolated left axillary lymph node metastasis approximately 10 months after undergoing resection of a left-sided abdominal wall port site recurrence for a T2 gallbladder cancer. The original tumor had been found at laparoscopic cholecystectomy and definitively treated surgically approximately 3 years earlier. The second case involves a patient who developed isolated nodal metastases to the right axillary lymph nodes approximately 4 months after undergoing resection of right-sided abdominal wall port site recurrence, segment 4/5 hepatic resection, and portal lymphadenectomy for a T2 gallbladder cancer. This tumor had originally been found at laparoscopic cholecystectomy approximately 1 year earlier. These unique sequelae of the interval development of nodal metastases to the axillary lymph nodes demonstrated in both cases has not been previously reported.

Abdominal Wall↗
PubMed2003

Radiofrequency ablation of invasive breast carcinoma followed by delayed surgical excision.

BACKGROUND: Radiofrequency ablation (RFA) is gaining acceptance as a treatment modality for several tumor types. However, its use in patients with breast carcinoma remains investigational. The current study was undertaken to determine the feasibility of treating small breast malignancies with RFA and to evaluate the postablation magnetic resonance imaging scans (MRI) and histologic findings. METHODS: Patients with core-needle biopsy-proven invasive carcinoma (< 2 cm in greatest dimension) underwent ultrasound-guided RFA under local anesthesia. Surgical excision was undertaken 1-3 weeks later. All patients had breast MRI scans performed before ablation and repeated within 24 hours of surgery. RESULTS: Ten patients completed the treatment and experienced minimal or no discomfort. The mean tumor size was 1.2 cm (range, 0.8-1.6 cm). The mean time required for ablation was 13.8 minutes (range, 7-21 minutes). There were no treatment-related complications other than minimal breast ecchymosis. A pre-RFA MRI scan showed enhancing tumors in 9 of 10 (90%) patients. A post-RFA MRI scan revealed no residual lesion enhancement in 8 of these 9 patients (89%), and the zone of ablation was demonstrated in all patients. One patient had residual enhancement anteriorly consistent with residual tumor, which was confirmed histologically. Evaluation of the remaining ablated lesions revealed a spectrum of changes ranging from no residual tumor to coagulation necrosis with recognizable malignant cells. Immunostains for cytokeratin 8/18 were negative in these recognizable malignant cells. CONCLUSIONS: RFA of small breast malignancies can be performed under local anesthesia in an office-based setting. A postablation MRI scan appears to predict histologic findings, although tumor viability needs to be assessed in a long-term study.

Adult↗
PubMed2003

Fistula involving portal vein and duodenum at the site of a duodenal ulcer in a patient after previous extrahepatic bile duct resection and brachytherapy.

Fistulas involving the portal venous system and gastrointestinal (GI) tract are rare. However, they can cause life-threatening GI hemorrhage. A case of a fistula between the main portal vein and the posterior wall of the duodenal bulb at the site of a duodenal ulcer in a patient who had previously undergone an extrahepatic bile duct resection and brachytherapy for mucinous cystadenocarcinoma is reported. Consideration should be given to this entity in the differential diagnosis of GI hemorrhage in patients with a history of previous major biliary surgery.

Adult↗
PubMed2003

Patterns of recurrence after sentinel lymph node biopsy for breast cancer.

BACKGROUND: Sentinel lymph node biopsy (SLNB) is gaining acceptance as an alternative to axillary lymph node dissection. The purpose of this study was to determine the frequency and pattern of disease recurrence after SLNB. METHODS: Two-hundred twenty-two consecutive patients undergoing SLNB from April 6, 1998, to October 27, 1999, and who were >or=24 months out from their procedure were identified from a prospectively maintained database. Retrospective chart review and data analysis were performed to identify variables predictive of recurrence. RESULTS: The median patient follow-up was 32 months (range, 24-43 months). A total of 159 patients (72%) were sentinel lymph node (SLN) negative and had no further axillary treatment. Five of these patients (3.1%) developed a recurrence (one local and four distant), with no isolated regional (axillary) recurrences. Sixty-three patients (28%) were SLN positive and underwent a subsequent axillary lymph node dissection. Six of these patients (9.5%) developed a recurrence (three local, one regional, and two distant). Pathologic tumor size (P <.001), lymphovascular invasion (P =.018), and a positive SLN (P =.048) were all statistically significantly associated with disease recurrence. CONCLUSIONS: With a minimum follow-up of 24 months, patients with a negative SLN and no subsequent axillary treatment demonstrate a low frequency of disease recurrence. This supports the use of SLNB as the sole axillary staging procedure in SLN-negative patients.

Adult↗
PubMed2002

Selective use of preoperative venous duplex ultrasound and intraoperative venography for central venous access device placement in cancer patients.

BACKGROUND: Central venous access in cancer patients is often challenging. A history of access is common. Appropriate indications for venous imaging studies are not clearly defined. METHODS: This study was a retrospective analysis of selective use of preoperative venous duplex ultrasound and intraoperative venography in 248 consecutive cancer patients undergoing central venous access placement. RESULTS: Ninety patients had a history of central venous access placement. Eleven had a history of deep venous thrombosis of an upper extremity or central vein. One hundred three underwent preoperative ultrasound. Previous central venous access placement was not associated with an abnormal preoperative ultrasound; however, previous central venous access with deep venous thrombosis was (P =.014). Thirty patients underwent intraoperative venography, of which 18 also had preoperative ultrasound. Fifty percent of patients with an abnormal intraoperative venogram had no abnormal findings on preoperative ultrasound. CONCLUSIONS: Routine preoperative ultrasound is unnecessary. We advocate the selective use of preoperative ultrasound in those with a history of central venous access associated with deep venous thrombosis. We advocate the use of intraoperative venography when there is difficulty advancing the guidewire or catheter or when preoperative ultrasound is negative despite a history of central venous access with deep venous thrombosis.

Adolescent↗
PubMed2002

Sentinel lymph node mapping and biopsy for breast cancer at a rural-based university medical center: initial experience with intraparenchymal and intradermal injection routes.

BACKGROUND: Recent data suggests that intradermal (ID) injection for sentinel lymph node (SLN) mapping and biopsy in breast cancer is as effective and reproducible as intraparenchymal (IP) injection. The aim of this study was to review our initial experience with IP and ID injection for SLN mapping and biopsy at our rural-based university medical center. METHODS: From January 4, 1999 to January 5, 2001, 113 of 165 patients with breast cancer underwent attempted SLN mapping and biopsy by either IP (n=63) or ID (n=50) injection. Selection of the IP versus ID injection route was non-randomized and based on surgeon preference. Success of SLN localization was examined. RESULTS: SLN localization was successful in 82% of IP and 100% of ID for radioisotope (p=0.001), 69% of IP and 92% of ID for blue dye (p=0.002), and 90% of IP and 100% of ID (p=0.024) for radioisotope and blue dye. Identical comparisons made after excluding the first 10 cases, 20 cases, and 30 cases from each injection group showed that the percentage of cases in each group in which the SLN localized changed minimally; however, some of the resultant p values eventually lost statistical significance. CONCLUSIONS: SLN localization was more successful by ID injection than by IP injection, thus favoring utilization of the ID injection route. The eventual loss of statistical power in some of the comparisons with increasing numbers of initial cases excluded may reflect differential learning curves of the two injection techniques; however, this may simply be a reflection of decreasing sample size used in each subsequent analysis. A prospective randomized trial comparing the IP and ID injection route may be warranted.

Academic Medical Centers↗
PubMedDate not supplied

Dermatitis, glossitis, stomatitis, cheilitis, anemia and weight loss: a classic presentation of pancreatic glucagonoma.

Glucagonomas are rare tumors. They are predominantly located in the body or tail of the pancreas and display a constellation of signs and symptoms referred to as glucagonoma syndrome. The term necrolytic migratory erythema is used to characterize the distinctive rash associated with this syndrome. This report describes a classic presentation consisting of dermatitis, glossitis, stomatitis, angular cheilitis, anemia, and weight loss that was associated with the finding of a pancreatic mass and a markedly elevated plasma glucagon level. After pancreatic resection, the patient had complete resolution of the rash and normalization of plasma glucagon.

Anemia↗
PubMedDate not supplied

Pancreatic cancer in West Virginia: results from a rural academic medical center.

Pancreatic cancer accounts for over 28,000 deaths a year in the United States. Since incidence rates and outcomes in a rural academic hospital setting have not previously been reported, we reviewed all patient records at Ruby Memorial Hospital in Morgantown from 1/90 to 12/99. Our study revealed 32,231 cancer patients during this time, of which 152 (0.5 percent) were diagnosed with pancreatic cancer. Only 32 (21.2 percent) patients had resectable tumors at time of diagnosis. The mean age of these patients was 67 years (range 34-83 years) and only 36 percent of operable patients were male. The majority of tumors (26 or 81 percent) were found in the pancreatic head, and 97 percent of the tumors were adenocarcinomas. Only three patients (9.3 percent) had well-differentiated tumors, with poorly and moderately differentiated histologies making up 40 percent and 50 percent, respectively. Operations performed included pancreaticoduodenectomy in 26 patients, total pancreatectomy in four patients, and distal pancreatectomy in two patients. There was only one perioperative death (3.1 percent). A total of 75 percent of the of the group underwent postoperative chemotherapy, mostly with fluorouracil-based monotherapy. Postoperative survival rate was 47 percent at one year, 25 percent at two years, and 9.6 percent at three years. No survival advantage was demonstrable in adjuvant treated patients. Our results show for the first time that pancreatic cancer is managed well in a rural hospital setting with equivalent short and long-term outcomes. The social and economic advantages of local patient care are supported by these results and warrant further study.

Academic Medical Centers↗