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S Alavi

Publications and source records attributed to S Alavi.

18 recordsLinked to original sources
PubMed2003

Can total and transition zone volume of the prostate determine whether to perform a repeat biopsy?

OBJECTIVES: To compare the ability of total prostate (TP) and transition zone (TZ) volume to predict the outcome of a repeat prostate biopsy in patients with serum prostate-specific antigen (PSA) levels of 4 to 10 ng/mL. METHODS: A total of 1137 patients were included and underwent transrectal ultrasound-guided needle sextant and two transition zone biopsies of the prostate. All patients with a prior negative biopsy (benign prostatic tissue) underwent a repeat biopsy after 6 weeks. The TP and TZ volumes of the prostate were measured by transrectal ultrasonography. RESULTS: Of the 1137 patients, prostate cancer was diagnosed in 364 (32%), in 276 (24.2%) after the first biopsy and in 88 (7.7%) after the repeated biopsy. The TP and TZ volumes were larger in the patients with prostate cancer detected on the repeated biopsy (P <0.0001). Using a cutoff for TP volume of less than 20 cm3 and greater than 80 cm3 and for TZ volume of less than 9 cm3 and greater than 41 cm3 would have spared 7.1% and 10% of repeated biopsies, respectively. CONCLUSIONS: The probability for a positive repeat prostate biopsy increases in a logarithmic function for larger prostates, as well as for larger TP and, especially, for larger TZ volumes. The probability of finding prostate cancer on a repeat biopsy in prostates with small (less than 20 cm3) and large (greater than 79 cm3) TP, as well as in small (less than 9.3 cm3) and large (greater than 41 cm3) TZ volumes, was very low. Therefore, a repeat prostate biopsy within 6 weeks is unnecessary. These patients should be followed up by serial PSA determination.

Aged↗
PubMed2001

Twelve-year experience with two courses of adjuvant single-agent carboplatin therapy for clinical stage I seminoma.

PURPOSE: During the past 30 years, radiation therapy with 28 to 30 Gy for para-aortic and ipsilateral iliac node areas was the standard adjuvant treatment for clinical stage I seminoma after orchiectomy. However, late effects of radiotherapy prompted a search for alternative adjuvant treatment approaches, including surveillance and application of carboplatin. In this retrospective analysis, we evaluated the efficacy and toxicity of two adjuvant single-agent carboplatin courses in 107 patients who were diagnosed with clinical stage I seminoma at our study centers between 1988 and 1999. PATIENTS AND METHODS: All 107 patients (median age, 39 years; range, 24 to 63 years) received two postoperative adjuvant cycles of carboplatin (400 mg/m(2)). The pathologic tumor stage was pT1 in 84 patients, pT2 in 18 patients, and pT3 in five patients. Whole blood count and serum chemistry were evaluated weekly during treatment to assess hematologic and nonhematologic toxicity. RESULTS: Six patients died from tumor-unrelated causes. The remaining 101 patients are currently alive and free of disease after a median follow-up of 74 months (range, 5 to 145 months). A detailed analysis of hematologic toxicity showed only World Health Organization (WHO) grade 1 leukocytopenia in 10.7% of all cycles and WHO grade 2 leukocytopenia in 2.1% of all cycles. CONCLUSION: Regarding the absence of tumor recurrences in our retrospective analysis and the favorable toxicity profile with no episodes of long-term toxicity, we suggest that two adjuvant courses of single-agent carboplatin for clinical stage I seminoma patients might be equivalent to radiotherapy.

Adult↗
PubMed2001

The role of hyperplasia in multiple parathyroid adenomas.

BACKGROUND: Parathyroid adenoma is the most common cause of primary hyperparathyroidism (pHPT). Adenomas usually involve only a single gland, and the remaining glands are normal or suppressed. Multiple parathyroid adenomas have been reported to occur in as high as 11% of patients with pHPT. The significant incidence of multiple adenomas with histologic similarities to hyperplasia has raised the possibility that adenoma is a continuation of the hyperplasia state. To test this theory, we used molecular genetics to compare clonality and proliferative activity of parathyroid adenoma with its corresponding normal glandular tissue. Furthermore, we devised a scheme to definitively distinguish between the different parathyroid states on a molecular level, because histologic distinction is unreliable. METHODS: The study included three patients with a diagnosis of singular parathyroid adenoma and three with double parathyroid adenomas. Paraffin-embedded surgical specimens of both adenomas and normal glands were retrieved from each patient. Clonal analysis of the phosphoglycerolkinase (PGK) gene has suggested that parathyroid adenomas are monoclonal. Clonality of parathyroid adenomas and normal parathyroid glands was studied by polymerase chain reaction-based restriction fragment length polymorphic analysis for the PGK gene. Proliferative activity of the specimens was also analyzed using the immunohistochemical markers PCNA and Ki-67. RESULTS: All adenomas were monoclonal and all normal parathyroid glands were polyclonal for the PGK gene in both the single and double adenoma specimens. All adenomas stained positive for proliferative activity. In the three patients with singular adenoma, proliferative activity was not detected in the normal parathyroid tissue. However, in the double adenoma group, two of the three patients showed hyperproliferative activity in the normal glands. CONCLUSION: Proliferative activity consistent with hyperplasia was present in some normal glands of multiple adenoma patients. Our observation supports the theory that multiple adenomas may be a continuation of the hyperplasia state.

Adenoma↗
PubMed2001

Adenoid cystic carcinoma of the base of the tongue.

A retrospective review of 14 patients with adenoid cystic carcinoma of the tongue treated between 1955 and 1997 was performed. Treatment consisted of surgery (n = 2), radiotherapy (n = 2), chemotherapy (n = 1), or combination therapy (n = 9). The 2-, 5-, and 10-year absolute survival rates were 92%, 79%, and 63%, respectively. Seventy-five percent of the patients who died of cancer succumbed to distant metastases. However, long-term survival was common despite a high incidence of local and distant recurrence. The presence of positive surgical margins, the incidence of regional metastases, the incidence of perineural invasion, the initial stage of disease, and the eventual development of locoregional recurrence and distant metastases did not significantly alter the survival rate. Surgical extirpation combined with postoperative radiotherapy is advocated for the treatment of adenoid cystic carcinoma of the tongue. Given the indolent nature of this disease process, surgery should be directed toward conservation of speech and swallowing function.

Adult↗
PubMed2000

Inducing desorption of organic molecules with a scanning tunneling microscope: theory and experiments.

A scanning-tunneling microscope has been used to induce efficient local desorption of benzene from Si(100) at low currents (<100 pA), sample biases (approximately -2.4 V) and temperatures (22 K). A theoretical model based upon first principles electronic structure calculations and quantum mechanical wave packet dynamics describes this process as occurring via transient ionization of a pi state of the adsorbed molecule. This model accounts for the unexpected efficiency and sharp threshold of the yield.

Adsorption↗
PubMed2000

Third branchial cleft anomaly presenting as a retropharyngeal abscess.

Branchial cleft anomalies are congenital developmental defects that typically present as a soft fluctuant mass or fistulous tract along the anterior border of the sternocleidomastoid muscle. However, branchial anomalies can manifest atypically, presenting diagnostic and therapeutic challenges. Error or delay in diagnosis can lead to complications, recurrences, and even life-threatening emergencies. We describe a case of an infected branchial cleft cyst that progressed to a retropharyngeal abscess in a 5-week-old female patient. The clinical, radiographic, and histologic findings of this rare presentation of branchial cleft cyst are discussed.

Anti-Bacterial Agents↗
PubMed2000

Controlling organic reactions on silicon surfaces with a scanning tunneling microscope: theoretical and experimental studies of resonance-mediated desorption.

The dynamics of tip-induced, resonance-mediated bond-breaking in complex organic adsorbates is studied theoretically and experimentally. Desorption of benzene from a Si(100) surface is found to be efficient and sensitive to voltage, the measured yield rising from below 10(-10) to ca. 10(-6) per electron within a ca. 0.8 V range at low (< 100 pA) current. A theoretical model, based upon first principles electronic structure calculations and quantum mechanical wavepacket simulations, traces these observations to multi-mode dynamics triggered by a transition into a cationic resonance. The model is generalized to provide understanding of, and suggest a means of control over, the behaviour of different classes of organic adsorbates under tunneling current.

Journal Article↗
PubMed2000

Microwave thermotherapy in patients with chronic urinary retention.

PURPOSE: To evaluate the efficacy of high-energy transurethral microwave thermotherapy (TUMT) in the treatment of chronic urinary retention (CUR) due to benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: In this prospective cohort study, 29 patients with CUR due to BPH underwent high-energy TUMT. Prior to treatment and during a 12-week follow-up, the following parameters were determined: quality of life (QOL) score, peak flow rate (Qmax) by uroflowmetry, and postvoid residual urine (PVR). In those with treatment failure (PVR > 150 mL or urinary retention), pressure-flow studies were performed and compared to pre-TUMT urodynamics. RESULTS: Of the 29 patients, 21 (72%) regained the ability to void spontaneously at 5 weeks. The actuarial median time for spontaneous voiding to be restored was 3.5 weeks (95% confidence interval [CI] 2.9-4.8 weeks). Mean QOL score at 12 weeks post-TUMT (2.2; 95% CI 1.5-2.7) was lower than that at 1 week (4.6; 95% CI 3.9-5.8) by 51% (p < 0.0005). Further, a 55% increase in mean Qmax (p < .0005) determined by uroflowmetry was observed by 12 weeks vs. 1 week after high-energy TUMT. TUMT failed in 8 patients due to a hypocontractile detrusor. CONCLUSIONS: We concluded that high-energy TUMT is a potentially useful option for patient with CUR who are not candidates for prostatectomy.

Aged↗
PubMed1999

Clinical application of fluorescence in situ hybridization for chromosome 11q13 analysis in head and neck cancer.

OBJECTIVE: Squamous cell carcinoma of the head and neck (HNSCC) still has one of the lowest 5-year survival rates. Despite advances in diagnosis, treatment, and research, survival rates have not improved in recent years. This report examines the utility of fluorescence in situ hybridization (FISH) in detecting chromosome 11q13 amplification in HNSCC and in evaluating the correlation between 11q13 amplification and tumor behavior. STUDY DESIGN: This study used FISH to determine the incidence of 11q13 amplification in 20 HNSCCs and 10 normal controls from the same patients. Tumor touch preparations and paraffin-embedded tissues from the same patient samples were used for comparative analysis. Both single and dual color FISH was performed. METHODS: Repetitive chromosome 11 specific alpha satellite DNA probe and chromosome 11q13 specific probe cyclin D1 were used for the FISH analysis. RESULTS: Experiments revealed amplification of chromosome 11q13 in three fresh touch preparations. FISH on paraffin tissues showed amplification in two additional samples. Intensity of amplification, as high as 20 copies per nucleus, was observed in paraffin preparations, whereas a maximum of only six copies was seen in fresh preparations. Amplification was not detected in any of the normal samples. All five cases with 11q13 amplification had metastases and four of these were from poorly differentiated tumors. In the nonamplified cases, 5 of 15 had metastases and 2 of 15 was poorly differentiated. CONCLUSIONS: The present study indicates that FISH is a useful technique for detecting molecular changes such as amplification of chromosome 11q13 in HNSCC. FISH in paraffin preparations allows for accurate measurement of intensity of amplification and makes it possible for the evaluation of a large collection of archival material. The data also suggest that 11q13 amplification is correlated with poorly differentiated tumors and metastasis. Thus FISH has the potential to be a valuable diagnostic/prognostic tool in head and neck cancers.

Adult↗
PubMed1999

Glandular carcinoma of the larynx: the UCLA experience.

Glandular carcinomas of the larynx are rare tumors that constitute less than 1% of all laryngeal malignancies. A retrospective case review of 12 patients with glandular carcinomas of the larynx is presented to identify patient and tumor characteristics, therapeutic modalities, and treatment outcomes. Ten patients underwent surgical excision of the primary tumor, by either supraglottic laryngectomy, vertical partial laryngectomy, or total laryngectomy. Seven of these patients also received postoperative radiotherapy. After a median follow-up period of 23 months, 7 of the 12 patients (58.3%) died as a result of uncontrolled locoregional disease or distant metastases. The 5-year survival rate was 57% in patients who underwent combination therapy versus 50% for those patients who received surgery alone. Surgical resection is the primary treatment modality used in the majority of cases. Neck dissection is reserved for patients with clinically apparent adenopathy, adenocarcinoma, or high-grade mucoepidermoid carcinoma. Combination therapy with surgical resection and radiotherapy may be more effective in achieving tumor remission than is surgical resection alone.

Adenocarcinoma↗
PubMed1999

Distant lymphatic metastasis from head and neck cancer.

A predictable pattern of metastasis based on tumor histology and site of origin has been well documented for most cancers that arise in the head and neck region. The current study demonstrates that this predictable pattern of metastasis can be significantly impacted by previous therapy, resulting in unusual patterns of metastasis in patients with recurrent tumors. A retrospective case series of 5 patients with head and neck carcinomas who developed metastases to distant lymph nodes is presented. All patients underwent surgery and radiotherapy to the primary tumor and regional lymphatics at the time of their initial treatment. All of the patients developed a local recurrence less than a year before the detection of distant lymphatic metastases. Cytology or excision confirmed metastases to the axillary, inguinal, or anterior intercostal lymph nodes. All of the patients underwent aggressive surgery for attempted cure of the local recurrence shortly before the presence of distant lymphatic metastases was clinically recognized. The metastatic workup of patients with carcinomas of the head and neck frequently includes examination of the regional lymph nodes as well as chest radiography, liver function tests, and serum calcium determination. This evaluation may fail to detect metastases to distant lymph nodes in patients who present with recurrent or second primary cancers. Such patients should undergo careful examination of all major lymph node-bearing regions of the body when being evaluated for the presence of distant metastases.

Aged↗
PubMed1997

Recurrent pleomorphic adenoma of the parotid gland involving the osseous external auditory canal. With a note on the foramen of Huschke.

A recurrence of a parotid pleomorphic adenoma presenting as an external ear canal mass is reported. The route of extension was radiographically documented as an incompletely closed foramen of Huschke. The historical and developmental features of this foramen and the mechanisms of tumor extension as they relate to it are discussed.

Adenoma, Pleomorphic↗
PubMed1995

Modified retrosigmoid approach: use for selected acoustic tumor removal.

The authors have used a modified retrosigmoid (suboccipital) approach for removal of acoustic tumors in selected patients who have good preoperative hearing and whose tumor does not reach the brain stem or extend to the lateral third of the internal auditory canal. This report presents the surgical technique and results for 15 acoustic neuromas removed by members of the House Ear Clinic between 1986 and 1991 using this approach. The technique differs importantly from the standard suboccipital approach. A mastoidectomy with decompression of the sigmoid sinus allows forward retraction of the sigmoid sinus, enabling tumor removal without cerebellar retraction. Also, replacement of the craniotomy flap prevents adherence to the dura of the scalp, which may prevent postoperative headaches. Tumor size ranged from 0.8 cm to 4.0 cm (mean, 1.9 cm). At 1 year or more postoperative, 13 of the 14 patients with follow-up available had a House-Brackmann (H-B) facial nerve grade I, and one patient had H-B grade II. Three patients retained good hearing ( < or = 30 dB SRT and > or = 70% speech discrimination) postoperatively, and 57% retained at least measurable hearing. For a patient with good preoperative hearing and a tumor that is medially based, involving the cerebellopontine angle but not extending to the brain stem or the lateral end or the internal auditory canal, the authors will continue to use the retrosigmoid approach for tumor removal.

Adult↗
PubMed1993

Cohen syndrome.

Explore the source record for details and available documents.

Abnormalities, Multiple↗
PubMedDate not supplied

Detection of chromosome 11q13 amplification in head and neck cancer using fluorescence in situ hybridization.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) remains a cancer with one of the lowest five-year survival rates. Despite a better understanding of the disease and recent advances in diagnosis and treatment, survival rates for HNSCC patients have not improved. Chromosomal abnormalities are common in HNSCC, and aberrations of chromosome 11q13 have been correlated with a poor prognosis. MATERIALS AND METHODS: In this study we utilized fluorescence in situ hybridization (FISH) to determine the incidence of 11q13 amplification in twenty primary HNSCC tumors. INT-2 was used as the 11q13 probe, and 9 and 11 centromeric probes were used as controls. RESULTS: Polysomy, greater than two copies of chromosome 11, was found in 2 of 20 tumors. INT2 (11q13) amplification was found in 3 other tumors. CONCLUSIONS: These preliminary studies indicate tht analysis of a larger sample of tumors using FISH may yield important diagnostic and prognostic information about head and neck tumors.

Adult↗
PubMedDate not supplied

The Proteus syndrome.

A race case of Proteus syndrome is presented. The main features of this hamartomatous condition are partial gigantism of hands and feet, hemihypertrophy, subcutaneous masses, epidermal nevi and bony abnormalities. The condition is extremely rare. Though the child had severe cosmetic disability, motor intellectual and language development was found to be normal.

Aftercare↗