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W D Wong

Publications and source records attributed to W D Wong.

At least 19 recordsLinked to original sources
PubMed2004

Neuroendocrine carcinomas of the colon and rectum.

PURPOSE: This study was designed to review experience with neuroendocrine carcinomas of the colon and rectum at a single institution, with emphasis on the pathology and clinical characteristics of this uncommon malignancy. METHODS: A study group of patients was identified from a prospective colorectal service database. Pathology was reviewed and neuroendocrine tumors were classified by a single pathologist. Medical records were retrospectively reviewed. RESULTS: From March 1975 to September 1998, 38 patients with neuroendocrine carcinomas were identified from the colorectal service database comprising 6495 patients (0.6 percent). These neuroendocrine carcinomas did not include carcinoid tumors. Average patient age was 57 years (range, 29-86 years). There were 17 males (44.7 percent) and 21 females (55.3 percent). Tumors were located as follows: 17 colon, 14 rectum, 6 anal canal, and 1 appendix. The diagnosis of neuroendocrine carcinoma was suggested preoperatively from tissue biopsy in 59.3 percent (16/27) of patients evaluable. Pathology was reviewed and tumors were categorized as small cell carcinoma (n = 22) or large cell neuroendocrine carcinoma (n = 16). Most tumors (20/25 evaluable, 80 percent) stained positive by means of immunohistochemistry for neuroendocrine markers, including chromogranin (18/19), synaptophysin (10/15), and/or neuron-specific enolase (14/15). Metastatic disease was detected at the time of diagnosis in 69.4 percent of the patients (25/36). Tumors were advanced at the time of diagnosis, with American Joint Committee on Cancer (AJCC) Stage I (n = 6), Stage III (n = 7), and Stage IV (n = 25) tumors. As a group, these tumors had a poor prognosis, with a median survival of 10.4 months. One-year, two-year, and three-year survival was 46 percent, 26 percent, and 13 percent, respectively. There was no significant difference in survival based on pathologic subtypes. Median follow-up time was 9.4 months (range, 0.6-263.7 months). CONCLUSIONS: Neuroendocrine carcinomas of the colon and rectum are uncommon, comprising less than 1 percent of colon and rectal cancers. Pathologically, these tumors are poorly differentiated carcinomas with distinctive cytoarchitectural features and are often immunoreactive for markers of neuroendocrine differentiation. The prognosis for high-grade neuroendocrine carcinomas is poor, as most patients have metastatic disease at the time of diagnosis.

Adult↗
PubMed2004

Surgical resection and high dose rate intraoperative radiation therapy for locally recurrent rectal cancer.

For intra-pelvic recurrence of rectal cancer, surgical resection is technically difficult and must be aggressive to achieve a high rate of negative resection margins. Resection with clear margins can be curative, particularly for those patients with true anastomotic recurrence. HDR-IORT is a safe, feasible, versatile, logistically sound modality that is highly reliable in delivering radiation to at-risk surgical margins in the pelvis. Despite surgery and IORT, overall local failure rates in this population are 33 to 50 percent. The most important prognostic variable is the state of surgical resection margins. At our institution, in patients with negative and positive resection margins the 2-year actuarial local recurrence rates are 33 percent versus 73 percent and 5-year survival rates are 51 percent versus 16 percent, respectively. On subset analysis, the most favorable outcome was seen in patients with true anastomotic recurrences (78 percent 5-year survival).

Combined Modality Therapy↗
PubMed2003

Results after rectal cancer resection with in-continuity partial vaginectomy and total mesorectal excision.

BACKGROUND: Although sharp mesorectal excision reduces circumferential margin involvement and local recurrence, a concomitant partial vaginectomy may be required in women with locally advanced rectal cancer. METHODS: Sixty-four patients requiring a partial vaginectomy during resection of primary rectal cancer were identified. Survival was determined by the Kaplan-Meier method, and distributions were compared by the log-rank test. RESULTS: Locally advanced disease was reflected by presentation with malignant rectovaginal fistulae (n = 6) or cancers described as bulky or adherent/tethered to the rectovaginal septum (n = 32). Thirty-five patients received adjuvant radiation with or without chemotherapy. At a median follow-up of 22 months, 27 (42%) patients developed recurrent disease, with most of these occurring at distant sites. The 5-year overall survival was 46%, with a median survival of 44 months. The 2-year local recurrence-free survival was 84%. The crude local failure rate was 16% (10 of 64), and local recurrence was more common in patients with a positive as opposed to a negative microscopic margin (2 [50%] of 4 vs. 8 [13%] of 60, respectively). Positive nodal status had a significant effect on overall survival (P <.001). CONCLUSIONS: Partial vaginectomy is indicated for locally advanced rectal cancers involving the vagina. The results are most favorable in patients with negative surgical margins and node-negative disease.

Adult↗
PubMed2003

Resection of locally recurrent colorectal cancer in the presence of distant metastases: can it be justified?

BACKGROUND: We aimed to determine the outcome of resections for local recurrence of colorectal carcinoma in the presence of distant (M1) disease. METHODS: Patients who underwent resection of local recurrence in the presence of potentially resectable M1 disease were identified from the colorectal database. Outcome was determined by chart review. RESULTS: Forty-two patients (23 men) of mean age 60 years (range, 34-88 years) underwent complete gross resection of their local recurrence in the presence of M1 disease. Thirteen of the 42 underwent synchronous M1 resections to render them free of gross disease (R0). Nine of the 29 patients who left with residual disease (R1) subsequently underwent staged M1 resection, so that 22 of 42 were rendered R0 by surgery. The median survival of all patients was 14.5 months (interquartile range, 6-30 months), and that of patients rendered R0 was 23 months (interquartile range, 10-37 months), in comparison with 7 months (interquartile range, 3-25 months) for those of R1 status (P =.006; log-rank method). Ability to achieve R0 status by synchronous or staged resection was the only factor predictive of survival. CONCLUSIONS: The presence of M1 disease per se should not preclude resection of local recurrence, although case selection is problematic.

Adult↗
PubMed2001

Surgical debulking and intraperitoneal chemotherapy for established peritoneal metastases from colon and appendix cancer.

BACKGROUND: Aggressive treatment of peritoneal metastases from colon cancer by surgical cytoreduction and infusional intraperitoneal (IP) chemotherapy may benefit selected patients. We reviewed our institutional experience to assess patient selection, complications, and outcome. METHODS: Patients having surgical debulking and IP 5-fluoro-2'-deoxyuridine (FUDR) plus leucovorin (LV) for peritoneal metastases from 1987 to 1999 were evaluated retrospectively. RESULTS: There were 64 patients with a mean age of 50 years. Primary tumor sites were 47 in the colon and 17 in the appendix. Peritoneal metastases were synchronous in 48 patients and metachronous in 16 patients. Patients received IP FUDR (1000 mg/m2 daily for 3 days) and IP leucovorin (240 mg/m2) with a median cycle number of 4 (range, 1-28). The median number of complications was 1 (range, 0-5), with no treatment related mortality. Only six patients (9%) required termination of IP chemotherapy because of complications. The median follow-up was 17 months (range, 0-132 months). The median survival was 34 months (range, 2-132); 5-year survival was 28%. Lymph node status, tumor grade, and interval to peritoneal metastasis were not statistically significant prognostic factors for survival. Complete tumor resection was significant on multivariate analysis (P = .04), with a 5-year survival of 54% for complete (n = 19) and 16% for incomplete (n = 45) resection. CONCLUSIONS: Surgical debulking and IP FUDR for peritoneal metastases from colon cancer can be accomplished safely and has yielded an overall 5-year survival of 28%. Complete resection is associated with improved survival (54% at 5 years) and is the most important prognostic indicator.

Adenocarcinoma↗
PubMed2000

Role of endorectal ultrasound in the conservative management of rectal cancers.

Endorectal ultrasonography (ERUS) extends the ability of the clinician to define the clinical features assessed on routine physical examination, and remains the best modality for accurately staging depth of penetration and presumptive nodal status in rectal cancers. The success of conservative management of rectal cancers is predicated on proper patient selection. The preoperative selection of the ideal patient for local therapies can be difficult, and the decision-making process takes into account many critical factors. Careful assessment of the T and N stages is critical in determining the success of conservative therapies, and directing treatment algorithms. Local resections with curative intent are limited to patients with T1N0 rectal cancers, and select patients with T2N0 tumors with favorable pathological criteria. Conservative management may also be extended to patients identified with significant underlying comorbid conditions staged preoperatively with unfavorable T2/T3 lesions, often combined with adjuvant therapies in a palliative setting. In addition, ERUS may have a role in the selection of those patients with more advanced lesions to neoadjuvant chemoradiation, followed by radical resection. Though not clearly defined, ERUS is evolving in its role in the postoperative follow-up of patients treated conservatively for rectal cancers, and can lead to the early detection of local recurrences. The widespread use of ERUS remains limited due to high operator variability and errors in interpretation; however, the role of ERUS in the postoperative management of rectal cancers is evolving and requires further evaluation.

Humans↗
PubMed2000

Standards for anal sphincter replacement.

PURPOSE: Anal sphincter replacement offers a new treatment option for patients with severe refractory fecal incontinence or for those who require abdominoperineal resection for localized malignancy. The purpose of this study was to review the current status of anal sphincter replacement, formulate a consensus statement regarding its current use, and outline suggestions for future development. METHODS: Four areas of interests were selected: indications for sphincter replacement, continence scoring and quality of life, choice of therapy, and dissemination of new technology. A questionnaire regarding these issues was developed and circulated to working party members; its results served as the basis for this consensus document. RESULTS: Both electrically stimulated skeletal muscle neosphincter and artificial anal sphincter are options for patients with end-stage fecal incontinence. Electrically stimulated skeletal muscle neosphincter is also appropriate for reconstruction after surgical excision of the anorectum in selected cases. Avoidance of complications requires strict attention to sterile technique, prophylactic antibiotics, and deep venous thrombus prophylaxis. A standardized scoring system is proposed that evaluates both continence and evacuation. Quality of life is a critical endpoint for assessing sphincter replacement, and use of The American Society of Colon and Rectal Surgeons incontinence-specific quality-of-life instrument is recommended. As the efficacy of sphincter replacement becomes proven, dissemination of the technique should occur in a controlled manner to ensure adequate surgeon training, minimization of complications, and optimization of results. CONCLUSIONS: Sphincter replacement by electrically stimulated skeletal muscle neosphincter and artificial anal sphincter provide a continent option for patients with end-stage fecal incontinence and those requiring abdominoperineal resection. The guidelines offered in this document are intended to facilitate the controlled and safe development and acceptance of these new techniques.

Anal Canal↗
PubMed2000

Functional and quality-of-life outcomes in patients with rectal cancer after combined modality therapy, intraoperative radiation therapy, and sphincter preservation.

PURPOSE: Locally advanced primary and recurrent rectal cancers treated with external beam radiation therapy, intraoperative radiation therapy, and chemotherapy represent a complex group of patients in the setting of extensive pelvic surgery and sphincter preservation. We sought to define functional outcome and quality of life in this subset of patients. METHODS: We retrospectively reviewed our experience with locally advanced primary and recurrent rectal cancer patients who underwent intraoperative radiation therapy with either low anterior resection (n = 12) or coloanal anastomosis (n = 6) between 1991 and 1998. Current functional outcome and quality of life were evaluated by a detailed questionnaire. RESULTS: Median time from operation to assessment was 24 (range, 6-93) months. Using a standardized Sphincter Function Scale, incorporating the number of bowel movements per day and degree of incontinence, patients were graded as poor, fair, good, or excellent function. Of all patients, 56 percent reported unfavorable (poor or fair) function. Of the subset of patients with coloanal anastomosis or very low low anterior resection, 88 percent had unfavorable function as compared with 30 percent with standard low anterior resection. (P = 0.02; Fisher's exact probability test). A quality-of-life satisfaction score based on social, professional, and recreational restrictions demonstrated 56 percent of patients to be dissatisfied with their bowel function. CONCLUSIONS: The majority of patients with advanced rectal cancers who require external beam radiation therapy, extensive pelvic surgery, and intraoperative radiation therapy report unfavorable functional and quality-of-life outcomes after sphincter preservation. In this setting patients being considered for coloanal anastomosis or very low anterior resection may be better served by permanent diversion.

Adult↗
PubMed2000

Practice parameters for the treatment of sigmoid diverticulitis--supporting documentation. The Standards Task Force. The American Society of Colon and Rectal Surgeons.

It should be recognized that these guidelines should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all of the circumstances presented by the individual patient.

Diverticulitis, Colonic↗
PubMed2000

Prokinetic effect of erythromycin after colorectal surgery: randomized, placebo-controlled, double-blind study.

PURPOSE: Nausea and vomiting three to seven days after an elective operation on the colon and rectum remain a persistent clinical problem. Erythromycin, a safe, inexpensive drug that stimulates intestinal motilin receptors, has previously been shown to accelerate gastric emptying significantly after upper gastrointestinal surgery. We aimed to evaluate the effect of postoperative intravenous erythromycin on postoperative ileus in patients undergoing elective surgery for primary colorectal cancer. METHODS: Between May 1998 and April 1999, 150 patients undergoing primary resection of colon or rectal cancer were enrolled in this prospective, randomized, placebo-controlled trial. One hundred thirty-four patients completed the study. Patients were excluded if they had extensive metastatic disease, were taking medications known to interact with erythromycin, or if they required an ileostomy. Patients received either 200 mg of intravenous erythromycin or placebo every six hours. Clinical endpoints were recorded and continuous end-points are presented as mean +/- standard deviation. RESULTS: There were no significant complications related to erythromycin. The erythromycin (n = 65) and placebo (n = 69) groups were comparable regarding demographic and operative factors. The erythromycin group had a slightly shorter length of time to passage of flatus (4.1 +/- 1.3 vs. 4.4 +/- 1.1 days; P = 0.03). There was no significant difference between erythromycin and placebo in time to first solid food (5.6 +/- 1.9 vs. 5.4 +/- 1.8 days), time to first bowel movement (5.2 +/- 1.9 vs. 5.4 +/- 1.3 days), or time to discharge from hospital (7.5 +/- 2.0 vs. 7.6 +/- 2.8 days). There was no difference in the rate of clinically significant nausea (26 vs. 26 percent; P = 0.99), vomiting (17 vs. 16 percent; P = 0.88), or nasogastric tube placement (9 vs. 7 percent; P = 0.68). CONCLUSIONS: Erythromycin does not seem to alter clinically important outcomes related to postoperative ileus in patients undergoing resection for colorectal cancer.

Aged↗
PubMed2000

Staging: what makes sense? Can the pathologist help?

The staging of colorectal cancer continues to be an interesting and evolving process. Accurate staging can predict overall prognosis and helps to select appropriate treatment options. This article addresses the clinical and pathologic staging of colon and rectal cancer. The use of endorectal ultrasound in the preoperative clinical staging of rectal cancer is reviewed. The importance of surgical resection margins, lymph node retrieval rates, and tumor markers is discussed.

Biomarkers, Tumor↗
PubMed1999

Malignant tumors of the anal canal: the spectrum of disease, treatment, and outcomes.

BACKGROUND: Cancers of the anal canal are a rare and diverse group of tumors of the gastrointestinal tract currently managed most often with surgery, chemoradiotherapy, or both. Previous investigations of cancer of the anal canal have reported on small numbers of patients, included only squamous histology, or included a select group of patients. The current study reviewed a large consecutive series of patients with cancer of the anal canal, including all histologies, who received chemoradiotherapy as the primary treatment modality. METHODS: The spectrum of pathology, treatment, and outcomes for 192 patients with malignant tumors of the anal canal over a 10-year period, from 1984 to 1994, was analyzed. Patient charts were reviewed for diagnosis, staging, treatment, survival, and recurrence rates. RESULTS: The pathologies of 192 patients (mean age, 58 years; 119 females and 73 males) included 143 (74%) with squamous cell carcinoma, 36 (19%) with adenocarcinoma, and 7 (4%) with melanoma. The remaining 6 patients (3%) were diagnosed with neuroendocrine tumors (2), carcinoid tumor (1), Kaposi sarcoma (1), leiomyosarcoma (1), or lymphoma (1). T classification distributions were T1 (3%), T2 (46%), T3 (28%), and T4 (12%). The overall crude 5-year survival and recurrence rates were 53% and 34%, respectively. Five-year survival rates were 57% for squamous cell carcinoma, 63% for adenocarcinoma, and 33% for melanoma. Five-year survival rates by T classification were T1 (62%), T2 (57%), T3 (45%), and T4 (17%). Twenty-one (15%) of the patients with squamous cell carcinoma underwent surgical therapy only, with a 5-year survival rate of 60% and a recurrence rate of 23% at 5 years. The remaining 122 patients (85%) with squamous cell carcinoma received chemoradiotherapy only, with a 5-year survival rate of 55% and a recurrence rate of 34% at 5 years. Salvage abdominal perineal resection for recurrent or persistent squamous cell carcinoma after chemoradiotherapy was performed on 13 patients, with 8 (62%) of them alive at a mean follow-up of 32 months. Twenty-two patients (61%) with adenocarcinoma of the anal canal were treated with surgery, and 14 patients (39%) underwent surgery with adjuvant chemoradiation therapy. The 5-year survival and recurrence rates were 63% and 21%, respectively. CONCLUSIONS: Chemoradiotherapy for patients with squamous cell carcinoma offers survival rates equivalent to surgical therapy and preserved sphincter function. Adenocarcinoma managed with surgery, with adjuvant therapy for selected patients, gives good results. Melanoma continues to be associated with a poor prognosis.

Adenocarcinoma↗
PubMed1999

Complete rectal prolapse: evolution of management and results.

UNLABELLED: Optional treatment for complete rectal prolapse remains controversial. PURPOSE: We reviewed our experience over a 19-year period to assess trends in choice of operation, recurrence rates, and functional results. METHODS: We identified 372 patients who underwent surgery for complete rectal prolapse between 1976 and 1994. Charts were reviewed and follow-up (median, 64: range, 12-231 months) was obtained by mailed questionnaire (149 patients; 40 percent) and telephone interview (35 patients; 9 percent). Functional results were obtained from 184 responders (49 percent). RESULTS: Median age of patients was 64 (11-100) years, and females outnumbered males by nine to one. One-hundred and eighty-eight patients (51 percent) were lost to follow-up; 183 patients (49 percent) underwent perineal rectosigmoidectomy, and 161 patients (43 percent) underwent abdominal rectopexy with bowel resection. The percentage of patients who underwent perineal rectosigmoidectomy increased from 22 percent in the first five years of the study to 79 percent in the most recent five years. Patients undergoing perineal rectosigmoidectomy were more likely to have associated medical problems as compared with patients undergoing abdominal rectopexy (61 vs. 30 percent, P = 0.00001). There was no significant difference in morbidity, with 14 percent for perineal rectosigmoidectomy vs. 20 percent for abdominal rectopexy. Abdominal procedures were associated with a longer length of stay as compared with perineal rectosigmoidectomy (8 vs. 5 days, P = 0.001). Perineal procedures, however, had a higher recurrence rate (16 vs. 5 percent, P = 0.002). Functional improvement was not significantly different, and most patients were satisfied with treatment and outcome. CONCLUSIONS: We conclude that abdominal rectopexy with bowel resection is associated with low recurrence rates. Perineal rectosigmoidectomy provides lower morbidity and shorter length of stay, but recurrence rates are much higher. Despite this, perineal rectosigmoidectomy has appeal as a lesser procedure for elderly patients or those patients in the high surgical risk category. For younger patients, the benefits of perineal rectosigmoidectomy being a lesser procedure must be weighed against a higher recurrence rate.Patient satisfaction]

Colon, Sigmoid↗
PubMed1999

Effect of delivery on anal sphincter morphology and function.

PURPOSE: Anal sphincter injury is a serious complication of childbirth, which may result in persistent anal incontinence. Occult injuries, visualized with endoanal ultrasonography, have previously been reported in up to 35 percent of females in a British study. The aim of the present study was to study anal sphincter morphology and function before and after delivery in primiparous females in the United States. METHODS: Thirty-eight primiparous patients (mean age, 31 years) were evaluated with endoanal ultrasonography, anal manometry, and pudendal nerve terminal motor latency during pregnancy and after delivery. Bowel function before and after delivery was recorded according to set questionnaires. Cesarean section was performed in three patients. RESULTS: Clinical sphincter tears, requiring primary repair, occurred in 15 percent of the patients. After delivery endoanal ultrasonography revealed disruptions in the external anal sphincter in six patients, but no patient had disruption in the internal anal sphincter. One patient had slight scarring in the external sphincter. Of the seven patients with pathologic findings at endoanal ultrasonography, the left pudendal latency increased after delivery (P < 0.05), and manometric results were reduced. Three of these seven patients had a third-degree or fourth-degree tear during delivery. All investigations were normal in the three patients who underwent cesarean section. CONCLUSIONS: The present study demonstrates a significant frequency of sphincter injuries (20 percent) after vaginal delivery. Obstetricians should be aware of this risk and explicitly inquire about incontinence symptoms at follow-up after delivery.

Adult↗
PubMed1999

Varying features of early age-of-onset "sporadic" and hereditary nonpolyposis colorectal cancer patients.

PURPOSE: Although the criteria for clinical diagnosis of hereditary nonpolyposis colorectal cancer are not fully agreed on, young age seems to be a common trait. The purpose of this study is to identify clinicopathologic features of hereditary nonpolyposis colorectal cancer in early age-of-onset colorectal cancer patients stratified as a function of family cancer history. METHODS: Two hundred thirty consecutive colorectal cancer patients 40 years or older at time of diagnosis were registered into an ongoing database during a ten-year period. Accurate family history was obtained via medical records, telephone calls, and questionnaires on 146 patients. According to extent of family history of cancer, patients were stratified into seven groups: 1) fulfilling Amsterdam criteria, 2) fulfilling less strict criteria, 3) having at least one first-degree relative with colorectal cancer, 4) having at least one distant relative with colorectal cancer, 5) having at least one first-degree relative with any cancer, 6) having at least one distant relative with any cancer, 7) having no family history of cancer. RESULTS: Twenty-two of 146 patients fulfilled Amsterdam and less strict hereditary nonpolyposis colorectal cancer criteria (15 percent). These hereditary nonpolyposis colorectal cancer patients were significantly younger (31 vs. 35 years; P = 0.0003) and had more metachronous colorectal cancer (27 percent vs. 2 percent; P = 0.007) and less colorectal cancer with nodal or metastatic spread than the non-hereditary nonpolyposis colorectal cancer patients (35 percent vs. 65 percent; P = 0.01). CONCLUSION: Precise familial cancer assessment in early age-of-onset colorectal cancer increases the yield of hereditary nonpolyposis colorectal cancer diagnosis. Because of the frequent development of metachronous colorectal cancer and favorable prognosis, extensive rather than segmental surgery should be considered in early age-of-onset colorectal cancer patients belonging to hereditary nonpolyposis colorectal cancer families.

Adolescent↗