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PubMed1995

The transposable element mariner can excise in non-drosophilid insects.

Plasmid-based excision assays performed in embryos of two non-drosophilid species using the mariner transposable element from Drosophila mauritiana resulted in empty excision sites identical to those observed after the excision of mariner from D. mauritiana chromosomes. In the presence of the autonomous mariner element Mos1, excision products were recovered from D. melanogaster, D. mauritiana and the blowfly Lucilia cuprina. When a hsp82 heat shock promoter-Mos1 construct was used to supply mariner transposase, excision products were also recovered from the Queensland fruitfly Bactrocera tryoni. Analysis of DNA sequences at empty excision sites led us to hypothesise that the mariner excision/repair process involves the formation of a heteroduplex at the excision breakpoint. The success of these assays suggests that they will provide a valuable tool for assessing the ability of mariner and mariner-like elements to function in non-drosophilid insects and for investigating the basic mechanisms of mariner excision and repair.

Animals↗

PubMed2000

Selective total mesorectal excision for rectal cancer.

PURPOSE: Total mesorectal excision has been advocated for rectal cancer, but its use in upper rectal and rectosigmoid tumors remains a point of debate. METHODS: One hundred seventeen patients with rectal cancers were subjected to a prospective policy of total mesorectal excision for mid and low rectal cancers and a wide (5 cm) distal margin mesorectal excision for upper rectal and rectosigmoid cancers. RESULTS: Forty-one patients underwent ultralow anterior resection, 10 underwent abdominoperineal excision, 64 had anterior resection and 2 had Hartmann's procedure. The median follow-up was 39 months. Forty-three patients had a defunctioning ileostomy. Three patients (7.3 percent) had anastomotic leaks after ultralow anterior resection with total mesorectal excision. Ninety-three patients had palliative resections. There were four locoregional recurrences in this group, giving an actuarial locoregional recurrence rate of 9.3 percent at five years. The actuarial locoregional recurrence rate after anterior resection was 6.5 percent at five years. The actuarial five-year cancer-specific survival rate was 81.4 percent at five years. CONCLUSION: These results demonstrate that a policy of wide excision of the mesorectum for upper rectal and rectosigmoid cancer and total mesorectal excision for mid and low rectal cancer is associated with a low locoregional recurrence rate and may be as efficacious as routine total mesorectal excision for all rectal cancers.

Adult↗

PubMed1998

Synergism between yeast nucleotide and base excision repair pathways in the protection against DNA methylation damage.

The treatment of cells with simple DNA methylating agents such as methyl methanesulfonate (MMS) results in genotoxic lesions, including 3-methyladenine which blocks DNA replication. All the organisms studied to date contain an alkylation-specific base excision repair pathway. In the yeast Saccharomyces cerevisiae, the base excision repair pathway is initiated by a Mag1 3-methyladenine DNA glycosylase that removes the damaged base, followed by the Apn1 apurinic/apyrimidinic endonuclease which cleaves the DNA strand at the abasic site for subsequent repair and synthesis. Several nucleotide excision repair pathway mutants display only slightly increased sensitivity to killing by MMS, indicating that nucleotide excision repair per se does not play a major role in the repair of DNA methylation damage. However, mag1 and apn1 mutants that are also defective in nucleotide excision repair are extremely sensitive to MMS-induced killing and the effects are synergistic. These observations suggest that nucleotide excision repair and alkylation-specific base excision repair provide alternative pathways for the repair of DNA methylation damage. In addition to their role in nucleotide excision repair, Rad1 and Rad10 form a complex that is involved in recombination repair. It was found that the apn1 rad1 and apn1 rad10 double mutants have a growth defect and are significantly more sensitive to MMS killing than apn1 rad2 and apn1 rad4 double mutants in a gradient plate assay. Furthermore, the apn1 rad1 double mutant increased both the spontaneous and MMS-induced mutation frequency. Thus, the recombination repair defects of rad1 and rad10 may confer an additional synergistic effect when combined with the apn1 mutation.

Carrier Proteins↗

PubMed1999

The Arabidopsis transposon Tag1 is active in rice, undergoing germinal transposition and restricted, late somatic excision.

Tag1 is an autonomous transposable element of Arabidopsis thaliana that displays tight developmental control of its excision during shoot development. To determine how Tag1 behaves in a monocotyledonous species, Tag1 was inserted in a 35S-GUS marker gene and the construct was introduced into rice. Tag1 showed somatic excision activity in four out of eleven transgenic lines examined. In leaves, excision was primarily restricted to vascular bundles and produced sectors composed of only a few cells. Excision events in flowers occurred predominantly in or near the major veins of the palea and lemma to produce small sectors. In roots, small sectors were evident, but they were few in number. These data show that the timing of Tag1 excision during rice shoot development is late and mimics the late excision behavior of Tag1 in Arabidopsis. One of the transgenic rice lines, which had a high frequency of somatic excision, produced several germinal revertants, one of which was characterized by a new Tag1 insertion band. The pattern of Tag1 transcripts and the footprint sequences left behind after excision in rice were found to be very similar to those in Arabidopsis. These results show that key properties of Tag1 transposition and behavior are conserved between monocots and dicots and that Tag1 has the potential to serve as an insertional mutagen in rice.

Arabidopsis↗

PubMed2004

Preoperative radiotherapy combined with intraoperative radiotherapy improve results of total mesorectal excision in patients with T3 rectal cancer.

PURPOSE: The survival advantage of preoperative radiotherapy in patients with rectal cancer is still a matter of debate, because its incremental benefit in the total mesorectal excision setting is unclear. This study was designed to evaluate early and long-term results of preoperative radiotherapy plus intraoperative radiotherapy in a homogeneous population of T3 middle and lower rectal cancer patients submitted to total mesorectal excision. METHODS: A series of 113 patients with middle and lower T3 rectal cancer consecutively submitted to total mesorectal excision at a single surgical unit from 1991 to 1997 were divided into two groups according to type of neoadjuvant treatment: preoperative radiotherapy (38 Gy) plus intraoperative radiotherapy (10 Gy; n = 69), and no preoperative treatment (total mesorectal excision; n = 44). Standard statistical analyses were used to evaluate early (downstaging, intraoperative factors, hospital morbidity, and mortality rates) and long-term results (recurrence and survival). RESULTS: Overall, 68.2 percent of patients were downstaged by the preoperative regimens (T0 specimens in 3 cases). Postoperative complications were comparable in the two groups. Five-year, disease-specific survival was 81.4 and 58.1 percent in preoperative radiotherapy plus intraoperative radiotherapy group and total mesorectal excision group, respectively (P = 0.052). Corresponding figures for disease-free survival were 73.1 and 57.2 percent in the two groups, respectively (P = 0.096). The rates of local recurrence at five years were 6.6 and 23.2 percent in preoperative radiotherapy plus intraoperative radiotherapy and total mesorectal excision groups, respectively (P = 0.017). CONCLUSIONS: Preoperative radiotherapy plus intraoperative radiotherapy associated with total mesorectal excision reduce local recurrence rate and improve survival in T3 rectal cancer compared with total mesorectal excision alone.

Adult↗

PubMed2005

Recurrence after transanal excision of T1 rectal cancer: should we be concerned?

PURPOSE: Transanal excision is an appealing treatment for low rectal cancers because of its low morbidity, mortality, and better functional results than transabdominal procedures. However, controversy exists about whether it compromises the potential for cure. Several, recent reports of high recurrence rates after local excision prompted us to review our results of transanal excision alone in patients with T1 rectal cancers. METHODS: All patients with T1 low rectal cancer undergoing local excision alone between 1980 through 1998 were reviewed for local recurrence, distant metastasis, disease-free interval, results of salvage surgery, and overall and disease-free survival. Demographics, tumor size, distance from anal verge, and preoperative endoluminal ultrasound results also were recorded. Patients with poorly differentiated tumors, perineural or lymphovascular invasion, or with mucinous component were excluded. RESULTS: Fifty-two patients underwent transanal excision during the study period. Five-year recurrence was estimated to be 29.38 percent (95 percent confidence interval, 15.39-43.48). For 52 patients, five-year, cancer-specific and overall survival rates were 89 and 75 percent respectively. Fourteen of 15 patients with recurrence underwent salvage treatment with 56.2 percent (95 percent confidence interval, 35.2-90) five-year survival rate. Gender, preoperative staging by endorectal ultrasound, distance from the anal verge, tumor size, location, and T1 status discovered after transanal excision of a villous adenoma did not influence local recurrence or tumor-specific survival. CONCLUSIONS: Transanal excision for T1 rectal tumors with low-grade malignancy has a high rate of recurrence. Although overall cancer survival rates might be regarded as satisfactory, this high recurrence and low salvage rate raises the issue about the role of transanal excision alone for early rectal cancer and the possible need for adjuvant therapy or increased role of resective surgery.

Aged↗

PubMedDate not supplied

Predictors of recurrence after local excision and postoperative chemoradiation therapy of adenocarcinoma of the rectum.

BACKGROUND: Local excision of rectal cancer preserves anal continence, bladder function, and normal sexual function. However, local recurrence after excision remains a significant problem. To further define the indications for local excision, we analyzed possible factors predictive of recurrence after local excision of rectal cancer. METHODS: The charts of all patients undergoing local excision of adenocarcinoma of the rectum between 1985 and 1995 at a single institution were reviewed. Patients with metastatic disease at the time of excision and patients treated preoperatively with chemoradiation therapy were excluded. All available slides were reviewed by a single pathologist, who assessed the depth of invasion; the presence or absence of vascular invasion, lymphatic invasion, perineural invasion, and lymphocytic infiltrate; the mucinous status; and the degree of differentiation. Using the log-rank test and Cox proportional hazards model, univariate and multivariate analyses were performed to identify predictors of recurrence. RESULTS: Ninety patients underwent local excision, 46 transanally and 44 using a Kraske approach. The breakdown of patients by tumor stage was as follows: Tis, 13%; T1, 41%; T2, 30%; T3, 15%; and Tx, 1%. Sixty-eight percent of patients with T1 tumors were treated with postoperative radiotherapy; all patients with T2 or T3 tumors were treated postoperatively with or without 5-fluorouracil. The median duration of follow-up was 51 months. The median tumor diameter was 2.5 cm (range, 0.4 to 7 cm), and the median distance of the tumor from the anal verge was 4.5 cm (range, 1 to 10 cm). The 4-year actuarial local disease-free survival rate broken down by tumor stage was as follows: Tis, 100%; T1, 95%; T2, 80%; and T3, 73%. The median time to local recurrence was 23 months (range, 7 to 61 months). Multivariate analysis showed that only tumor stage and margin status were predictors of local recurrence. CONCLUSIONS: Local excision and postoperative radiotherapy result in adequate local control of early stage (Tis and T1) adenocarcinoma of the rectum. Higher rates of recurrence were seen in patients with T2 and T3 tumors, especially in those with positive margins.

Adenocarcinoma↗

PubMed1995

The suitability of the micronucleus assay in human lymphocytes as a new biomarker of excision repair.

The cytokinesis blocked micronucleus assay is relatively insensitive to detect agents that predominantly induce excision repairable DNA lesions. However, it has been recently proposed that excision-repairable DNA lesions induced in G0/G1 phase can be converted to micronuclei by using inhibitors of the gap filling step of excision repair so that unfilled gaps are converted to double stranded breaks after S phase and micronuclei (MN) at completion of mitosis. As it has been recently demonstrated this process could be improved by combining cytosine arabinoside (ARA-C) and hydroxyurea (HU). In the present work, we have investigated the suitability of this new approach by studying its ability to detect excision repairable DNA lesions induced by 10 pesticides (alachlor, atrazine, cypermethrin, deltamethrin, fenpropathrin, fenvalerate, maleic hydrazide, paraquat, permethrin and trifluralin) and 3 well-known mutagenic agents (ethyl methane sulphonate, EMS; methylnitrosourea, MNU; and mytomicin C, MMC). Our results showed that the combination of ARA-C and HU substantially increased the level of MN in whole blood lymphocyte cultures, but it provided an excess of toxicity when further treatments, such as MNU, were performed. When ARA-C alone was used, the ARA/CBMN assay appeared to be highly sensitive and specific in detecting agents known to induce excision repairable DNA lesions. Thus, EMS and MNU but not MMC greatly induced DNA excision repair. On the other hand, alachlor, permethrin and, to a lesser extent, trifluralin and fenpropathrin also increased the ratio of excision repairable DNA lesions converted to MN. On the contrary, atrazine, cypermethrin, deltamethrin, fenvalerate, maleic hydrazide and paraquat did not induce excision repair.

Adult↗

PubMed1987

A model for the recA-dependent repair of excision gaps in UV-irradiated Escherichia coli.

We have tested and supported the hypothesis that, in UV-irradiated Escherichia coli, recA-dependent nucleotide excision repair only functions in the replicated portion of the chromosome (i.e., where sister duplexes exist). Using a dnaA(Ts) mutation to align the chromosomes (i.e., all rounds of DNA replication were completed, and new rounds could not be initiated), we studied the genetic control of excision repair (measured as the repair of excision gaps in DNA) in cells with unreplicated chromosomes, and also in cells with partially replicated chromosomes. The excision repair that occurred in cells with unreplicated chromosomes was recA independent, but the excision repair that occurred in cells with partially replicated chromosomes was partially recA dependent. We found no evidence of interchromosomal recombination in recA-dependent excision repair. The majority of this recA-dependent excision repair was recF dependent, and a small portion was recB dependent. The recF and recB genes are suggested to function in excision repair in a manner similar to their function in postreplication repair, i.e., in the replicated portion of a chromosome, the RecF pathway repairs gaps, and the RecB pathway repairs the DNA double-strand breaks that arise at unrepaired gaps.

Chromosomes, Bacterial↗

PubMed1995

Comparison of wound closure by means of dog ear repair and elliptical excision.

BACKGROUND: Elliptical excision is a standard method of skin tumor removal. The technique commits the operator to the direction and length of wound closure before lesion excision and hence before the shape and size of the resulting defect is known. OBJECTIVE: This study was designed to compare the predicted results of elliptical excision with those achieved after tumor excision and dog ear repair. METHODS: Fifty-one patients with benign and malignant skin tumors were prospectively studied. Each lesion was examined and an optimal ellipse designed and marked on the skin. Only the lesion and the required margin of adjacent skin were excised before the defect was closed in an optimal direction. Dog ears were removed if appropriate. Precise measurements were made at each step. RESULTS: Twenty-eight percent of wounds could be closed with a flat sutured wound without the need for dog ear repair, 38% required one dog ear repair, and 34% two. Overall, the sutured wound length was 21% shorter and the wound direction different from the predicted ellipse in 45% of cases. CONCLUSION: Excision with dog ear repair results in significantly shorter and potentially better oriented wounds than those achieved by elliptical excision. For excision and closure of skin tumors this technique should be considered as the method of choice.

Adolescent↗

PubMed1995

Relation between size of skin excision, wound, and specimen.

BACKGROUND: Skin wounds differ in shape and size compared with the planned excision, and skin shrinks after excision and fixation. OBJECTIVE: This study was designed to quantify and to analyze the differences between the size and shape of the planned excision, wound, and specimen. METHODS: Eighty-six patients with 93 benign or malignant skin tumors were prospectively studied. Length and width measurements were made of the lesion, planned surgical excision, postexcision wound, and prefixation and postfixation specimens. The results were analyzed to identify the effects of patient age and sex, and lesion type and site. RESULTS: Wound size was larger than planned excision size in 90% of wounds, and this effect was greatest in young patients and at trunk and limb sites. Excision and fixation caused the specimens to shrink so that the postfixation area was on average 48% of the planned excision area; benign tumors shrank more than malignant tumors. CONCLUSION: Significant differences among planned excision, wound, and specimen sizes are influenced by patient age and by lesion site and type. These results demonstrate that wound size is not equivalent to tumor size, a conclusion often made in Mohs surgery. Furthermore, assessment of tumor clearance margins from fixed tissue does not reflect in vivo clearance margins.

Adolescent↗

PubMed1993

Inhibition of dimer excision in repeatedly UV-irradiated Escherichia coli: its requirement for RecA protein and de novo protein synthesis.

In UV-irradiated Escherichia coli dimer excision was found to be inhibited by predamage (M. Sedliaková, F. Masek and J. Brozmanová, FEBS Lett., 23 (1972) 325-326) or overproduction of RecA protein, which suggests that the coating of the dimers by this protein may make them inaccessible to the excision nuclease (M. Sedliaková, K. Kleibl and F. Masek, Mutat. Res., 191 (1987) 13-16). We measured the levels of RecA protein and dimer excision in cells irradiated with (i) a single dose of 50 J m-2, (ii) two separate doses of 30 and 50 J m-2, post-incubated with chloramphenicol; (iii) two separate doses of 30 and 50 J m-2, post-incubated without chloramphenicol. Dimer excision was complete in the first two cases, but in the latter it was inhibited by 40%. At the time of active dimer excision, there were marked differences in RecA protein content between the cells irradiated with a single dose and cells irradiated with two separate doses (both post-incubated without chloramphenicol), which might account for the differences in dimer excision. However, relatively small differences in RecA protein content were found in cells irradiated with two doses and post-incubated with or without chloramphenicol, which could therefore not account for the differences in dimer excision. The data suggest that the inhibition of dimer excision involves some short-lived component(s) other than RecA protein.

Bacterial Proteins↗

PubMed2006

Re-excision of margins before breast radiation-diagnostic or therapeutic?

PURPOSE: To identify factors in breast cancer patients that predict the pathologic results of re-excision for close or positive margins and to determine the effect on local control. METHODS AND MATERIALS: We divided 1,044 patients with Stage I-II breast cancer with a close (< or =2 mm) or positive margin after initial excision into three groups. Group 1 included 199 patients without additional excision, Group 2 included 546 patients with re-excision found to be free of cancer, and Group 3 included 299 patients with re-excision and residual cancer. All patients were treated with radiotherapy with a median follow-up of 6.7 years. RESULTS: The 10-year local control rate was 95% for Group 1 and 94% for Groups 2 and 3 (p = 0.788). Of the 846 patients, 65% had no residual disease on re-excision and 35% did have residual tumor. The factors significantly associated with positive re-excision findings were initial positive margins, positive nodes, Stage T2 tumor, and an extensive intraductal component. The 10-year local control rate was 95% for Group 2 vs. 91% for Group 3 (p = 0.038). CONCLUSION: The low recurrence rates seen in this study suggest that selected patients with non-negative margins, particularly those with a low risk of having residual disease at re-excision, may be treated with radiotherapy.

Adult↗

PubMed2006

Planning the breast tumor bed boost: changes in the excision cavity volume and surgical scar location after breast-conserving surgery and whole-breast irradiation.

PURPOSE: The aims of this study were to determine the changes in breast and excision cavity volumes after whole-breast irradiation and the adequacy of using the surgical scar to guide boost planning. METHODS AND MATERIALS: A total of 30 women consecutively treated for 31 breast cancers were included in this study. Simulation CT scans were performed before and after whole-breast irradiation. CT breast volumes were delineated using clinically defined borders. Excision cavity volumes were contoured based on surgical clips, the presence of a hematoma, and/or other surgical changes. Hypothetical electron boost plans were generated using the surgical scar with a 3-cm margin and analyzed for coverage. RESULTS: The mean CT breast volumes were 774 and 761 cc (p = 0.22), and the excision cavity volumes were 32.1 and 25.1 cc (p < 0.0001), before and after 40 Gy (39-42 Gy) of whole-breast irradiation, respectively. The volume reduction in the excision cavity was inversely correlated with time elapsed since surgery (R = 0.46, p < 0.01) and body weight (R = 0.50, p < 0.01). The scar-guided hypothetical plans failed to cover the excision cavity adequately in 62% and 53.8% of cases using the pretreatment and postradiation CTs, respectively. Per the hypothetical plans, the minimum dose to the excision cavity was significantly lower for tumors located in the inner vs. outer quadrants (p = 0.02) and for cavities >20 cc vs. <20 cc (p = 0.01). CONCLUSIONS: This study demonstrates a significant reduction in the volume of the excision cavity during whole-breast irradiation. Scar-guided boost plans provide inadequate coverage of the excision cavity in the majority of cases.

Adult↗

PubMed2005

Efficacy of narrow-margin excision of well-demarcated primary facial basal cell carcinomas.

BACKGROUND: A 4-mm surgical margin of clinically normal skin is the current standard for elliptical excision of basal cell carcinomas (BCCs). However, a 4-mm surgical margin is often not feasible on the face because of cosmetic and functional concerns. As such, facial excisions of BCCs are typically performed with the appropriate margin determined by the surgeon based on clinical features of the tumor. OBJECTIVE: We designed a study to test the efficacy of narrow-margin elliptical excisions for the treatment of small, well-demarcated facial BCCs. METHODS: A total of 134 primary, small (<1 cm), well-demarcated, facial nodular BCCs were excised as an ellipse with 1-, 2-, or 3-mm margins around the visible border of the tumor. The margin used was decided by the dermatologic surgeon based on cosmetic, anatomic, and functional factors, with the goal of clearing the tumor in a single excision. Using the Mohs technique for elliptical specimens, frozen sections were prepared and examined microscopically to provide complete histologic margin control. RESULTS: In all, 134 facial BCCs were included in the study. On average, the tumors measured 0.6 x 0.5 cm. Of these, 27 (20.1%) had positive margins, requiring additional excision. Excisions with 1-, 2-, and 3-mm margins were associated with positive margins in 16%, 24%, and 13% of tumors, respectively. There was no statistically significant difference in the occurrence of positive margins based on tumor size, anatomic location, or the measured margin used. CONCLUSION: Narrow margins (1-3 mm) are inadequate for the excision of small, well-demarcated, primary nodular BCCs of the face. To avoid repetitive operations and the risk of recurrence in anatomically sensitive areas, these tumors should be treated with standard wide margins (eg, 4 mm), or have Mohs micrographic surgery for histologic margin control.

Basal Cell Carcinoma↗

PubMed2004

The effect of partial A2 pulley excision on gliding resistance and pulley strength in vitro.

PURPOSE: The purpose of this study was to investigate the effect of partial excision of the A2 pulley on the gliding resistance and the strength of the residual pulleys in a human in vitro model with or without tendon repair. METHODS: We used 32 cadaveric human fingers from 11 cadavers. The A2 pulley was excised successively 25%, 50%, and 75%, cutting either from the distal toward the proximal edge or from the proximal toward the distal edge. The peak gliding resistance between intact or repaired tendon and partially excised pulley was measured. After the gliding resistance test the pulley breaking strength and stiffness were measured. RESULTS: The peak gliding resistance exhibited the same statistical trends for the intact tendon and the repaired tendon groups. In the intact tendon groups the sequential excision of the A2 pulley from the distal toward the proximal edge had no significant effect on peak gliding resistance. With the A2 pulley cut from the proximal toward the distal edge, however, there was a significant increase in peak gliding resistance with 25% remaining pulley distally (0.82 N) compared with intact (0.42 N), 75% (0.57 N), and 50% (0.63 N) pulley remaining proximally. The 25% distal portion of the A2 pulley had a significantly higher breaking strength than the 25% proximal portion (160 N vs 96.7 N, respectively). Similarly the stiffness was greater in the distal portion compared with the proximal portion (120 N/mm vs 70.5 N/mm). CONCLUSIONS: After A2 pulley excision the size and location of the remaining pulley affects the resulting gliding resistance, stiffness, and failure strength. At the most extreme excision level tested the residual 25% distal segment of the pulley exhibited significantly greater peak gliding resistance compared with the 25% proximal segment, as well as greater strength and stiffness. If excision of the A2 pulley is limited to 50% (either proximally or distally), however, there is little increase in gliding resistance and the retained strength of the pulley is substantial. These data support the clinical practice of partial pulley excision, up to a limit of 50%, to facilitate exposure and tendon repair.

Aged↗

PubMed1997

Involvement of recA and recF in the induced precise excision of Tn10 in Escherichia coli.

It has been shown that the increased frequency of precise excision of Tn10 observed after UV or mitomycin C (MMC) treatment or with uvrD- mutants is recA-dependent. Previous work has also shown that expression of SOS genes is required for UV- or MMC-induced Tn10 precise excision. In order to determine if the increased excision of Tn10 in uvrD- mutants requires only expression of recA, or expression of other SOS genes, or both, we studied the precise excision of Tn10 in lexA3 (Ind-, SOS non-inducible) and lexA3 recAo98 (operator constitutive recA) mutants. The results of these experiments indicate that the induced excision of Tn10 in the uvrD- null mutant depends on the expression of recA rather than on any of the other genes repressed by LexA. The effect of a null recF mutation on the excision of Tn10 in a uvrD- mutant was also investigated and found to abolish the increased frequencies of this process. Similarly, the recF mutation was found to decrease markedly the increased precise excision of Tn10 induced by MMC in a uvrD+ isogenic strain. These observations indicate that recA and recF are involved in the increased frequencies of Tn10 excision exhibited by uvrD- mutants or after MMC treatment. It remains to be determined whether these two genes participate in these two induction processes in the same biochemical pathways.

Adenosine Triphosphatases↗

PubMed1998

Early prostate-specific antigen failure following radical perineal versus retropubic prostatectomy: the importance of seminal vesicle excision.

OBJECTIVES: Because of renewed interest in the radical perineal prostatectomy, we chose to evaluate factors influencing differences in biochemical failure as measured by prostate-specific antigen (PSA) between radical perineal and the radical retropubic prostatectomies. METHODS: We undertook a retrospective review of 87 men with clinically localized prostate cancer who underwent radical retropubic (64%) or radical perineal (36%) prostatectomy, noting age, race, preoperative PSA, Gleason score, clinical stage, capsular penetration, surgical approach, and completeness of seminal vesicle (SV) excision. The two groups were comparable with respect to tumor factors such as preoperative PSA, Gleason score, clinical stage, and capsular penetration. Time to postoperative PSA failure (0.2 ng/mL or greater) was evaluated with univariate and multivariate analysis of multiple contributing factors. RESULTS: Twenty-eight percent of patients had a PSA level rising to 0.2 ng/mL or greater in the follow-up period. Patients who underwent perineal prostatectomy had a higher PSA failure rate (45%) than those treated by the retropubic approach (18%) and patients with incomplete SV excision had a higher failure rate (69%) than patients with bilateral SV excision (20%). When time to PSA failure was examined by multivariate analysis, completeness of SV excision, clinical stage, and Gleason score had a statistically significant impact on this outcome. In perineal prostatectomy patients, bilateral SV excision had a significantly longer time to PSA failure than in patients with incomplete excision. There was no significant difference in time to PSA failure between patients who underwent radical retropubic prostatectomy and the patients who underwent perineal prostatectomy with bilateral SV excision. CONCLUSIONS: Incomplete excision of SVs during a radical perineal prostatectomy contributes to an earlier postoperative biochemical recurrence as measured by a rising PSA, and may explain the higher disease recurrence rate for radical perineal prostatectomies as opposed to radical retropubic prostatectomies in this study.

Adult↗