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K C Soo

Publications and source records attributed to K C Soo.

At least 55 records · Page 3Linked to original sources
PubMed1998

Cystic tumours of the pancreas: a diagnostic dilemma.

BACKGROUND: Cystic neoplasm of the pancreas is an uncommon entity that encompasses a range of tumours with varying potential for malignancy. These tumours are frequently misdiagnosed as pseudocysts and are inappropriately managed. METHODS: A retrospective review was undertaken of 18 cases of cystic tumours of the pancreas over an 8-year period in two large hospitals in Singapore. RESULTS: All patients were Asian, with a younger age group (mean 43.5 years) and a lesser degree of female predominance (3.5:1 ratio) compared to other series. Pain was the most common symptom. Pre-operative diagnosis using ultrasound and computed tomography was not diagnostic in half of the cases and misdiagnosed as pseudocyst in a sixth. There were five serous cystadenomas, four mucinous cystadenomas, two mucinous cystadenocarcinomas, one mucinous cystadenocarcinoma with cystic degeneration in a ductal adenocarcinoma, three Frantz tumours, one acinar cell tumour, one glucagonoma, and one benign epithelial cyst. Two-thirds of tumours were malignant or had the potential to become malignant. Resection was curative in all cases, and no recurrence was noted at a mean follow-up of 34.5 months. CONCLUSIONS: The difficulties with pre-operative diagnosis, the high incidence of tumours with potential malignancy, and the good outcome with resection, suggest that all suspected cystic tumours of the pancreas should be resected.

Adenocarcinoma↗
PubMed1998

Primary reconstruction after extensive chest wall resection.

BACKGROUND: Chest wall resection and reconstruction has been proven to be a safe surgical procedure. This is particularly useful for breast cancer patients with chest wall recurrences or for those who first present with locally advanced cancer in the chest wall where there is both a large soft tissue and bony defect that need repair. In addition, many of these patients have had irradiation or chemotherapy, which can significantly impair wound healing. METHODS: Thirty-four patients underwent chest wall resection and primary reconstruction over an 8-year period. RESULTS: Twenty-three patients had breast carcinomas and six had breast and chest wall sarcomas. Of the breast carcinoma patients, 12 had local recurrences and 11 presented with locally advanced primary disease. Bony resection of the chest wall was required in 16 (47%) cases. Thirty myocutaneous flaps (18 rectus abdominis, four pectoralis major, eight latissimus dorsi) and three omental flaps were used for reconstruction. One required a deltovertebral skin flap. Skeletal reconstruction was necessary in four cases. All except one (97%) achieved primary wound healing. There was one mortality (3%) and three patients required further surgery for complications that were related to the reconstruction. Post-resection metastases occurred in 13 (42%) patients and only 2 (6%) had local recurrences. The 2-year survival rate was 78% with a mean survival time of 25.5 months. CONCLUSIONS: Primary reconstruction for curative or palliative purposes is a useful and safe surgical procedure for patients with recurrent or locally advanced chest malignancies after extensive chest wall resection. Pedicled myocutaneous flap is the preferred option for skeletal and soft-tissue coverage.

Bone Neoplasms↗
PubMed1998

The role for preoperative localisation techniques in surgery for hyperparathyroidism.

Preoperative localisation procedures in primary hyperparathyroidism have been associated with advantages like decreased operative dissection, shorter operating time and in some series, lower morbidity and mortality. However, successful identification of parathyroid glands exceeding 90% is achievable at surgery without preoperative localisation studies. Sixty-nine patients who underwent parathyroidectomy at the Department of Surgery, Singapore General Hospital, between March 1990 and July 1996 were analysed to determine the role of preoperative localisation techniques. Preoperative localisation of parathyroid glands consisted of computed tomographic (CT) scan in 66.7% of patients, technetium99 sestamibi scan in 23.2%, ultrasound in 15.9% and angiographic localisation in 4.3% of the patients. In the 28 end stage renal failure patients who were operated for progressive renal osteodystrophy, 6 had preceding renal transplants. The success of identifying parathyroid glands at operation in these 28 patients was independent of CT scan findings. CT scan was correct in only 6% of patients while surgical exploration had a success rate of 100%. Of the 41 patients with primary hyperparathyroidism, the success of CT scan in identifying enlarged parathyroid glands was 41.4% compared to 91.6% via surgical exploration. Furthermore, CT scan was not able to discriminate between superior and inferior parathyroid glands. Preoperative Tc-99m sestamibi scan and ultrasound correctly localised pathologic parathyroid gland in 40% and 18.2% of the patients, respectively. Therefore, the use of preoperative imaging to localise parathyroid glands before the intended exploration was found not to be useful in our series.

Adult↗
PubMed1998

Surgical treatment of thyroid cancer: the Singapore General Hospital experience.

Patients with differentiated thyroid cancers generally have a good prognosis. This should be considered when deciding the extent of surgical resection. Radical surgery, however, may be appropriate in the control of locally advanced disease. An audit of 149 cases of thyroid cancer treated in the Department of General Surgery, Singapore General Hospital between October 1988 and June 1994 is presented. Particular attention is drawn to eight patients who underwent radical surgery. There were 111 (74.5%) women and 38 (25.5%) men. The median age was 45 years (range 12 to 83 years) and 80.5% of the cancers were papillary carcinomas, 14.8% follicular, 2.7% medullary and 2.0% anaplastic. Total or near-total thyroidectomy was the most common procedure for primary disease in about 75% of patients. Eight patients (5.4%) underwent radical surgery-four laryngectomy, one pharyngectomy and three median sternotomy-for tumour clearance. Morbidity included: wound complications in 2%; hypocalcaemia, transient in 16.8% and permanent in 3.4%; and hoarseness of voice in 8.1% with 4.7% having proved recurrent laryngeal nerve palsy. All three patients with anaplastic thyroid cancer died within 3 months. Of the eight who underwent radical surgery, three (37.5%) are alive and disease-free at median follow-up of 20 months. In a correctly selected group of patients with locally invasive differentiated thyroid cancer, aggressive surgery is appropriate, with acceptable morbidity and mortality.

Adolescent↗
PubMed1998

Adjuvant chemotherapy for patients with resected Dukes' C and high-risk B2 colon cancer with fluorouracil and levamisole.

Carcinoma of the large bowel is the second leading cause of cancer mortality in Singapore. Although the great majority of patients are discovered at a stage where resection with curative intent is possible, almost half of the patients afflicted will die of it. The combination of 5-fluorouracil + levamisole used in patients with curatively resected high risk Dukes B2 and all Dukes' C colon cancers has been shown to reduce cancer recurrence rate and improve overall survival. Since 1990 adjuvant chemotherapy has been recommended for this group of patients. This report describes patients treated in Singapore, their toxicities and their outcome. A total of 341 patients were treated between 1990 and 1996. Treatment compliance was 71.8%. Toxicity was moderate with mainly grade 1-2 nausea and vomiting, diarrhoea, stomatitis, alopecia, and neutropenia. There was 1 treatment-related death. Median recurrence-free interval was 81 months and median survival was not reached at 90 months. This regimen is tolerable. Until further randomised reports comparing 5-fluorouracil + levamisole to other combinations are available, this combination chemotherapy is recommended to patients after surgical resection of the high risk Dukes' B2 and Dukes' C colon cancer to reduce cancer recurrence and improve overall survival.

Adenocarcinoma↗
PubMed1997

Risk factors for breast carcinoma in Singaporean Chinese women: the role of central obesity.

BACKGROUND: The incidence of breast carcinoma in Singapore has nearly doubled over the past 25 years. This prospective case-control study involving 1086 women (204 cases and 882 controls) was conducted to determine significant factors associated with the risk of breast carcinoma among Chinese women in Singapore ages 45 to 69 years. METHODS: A forward stepwise logistic regression model adjusted for confounding variables of age, age at menarche, menopausal status, parity, age at first and last delivery, use of oral contraceptives, hormone replacement therapy, family history of breast carcinoma, history of benign breast biopsy, smoking history, height, weight, body mass index, and waist to hip ratio was used. RESULTS: Central obesity as indicated by women with a larger waist to hip ratio was associated with highest risk for breast carcinoma (odds ratio [OR]: 9.18; 95% confidence interval [CI],4.8-17.5 comparing last and first quintile; P < 0.0001, chi-square test for trend). Significant trends were also noted for increasing height and breast carcinoma risk (P = 0.003, chi-square test). Women who were taller than 159 cm (OR: 2.3; 95% CI, 1.4-3.9) had approximately twice the risk of women shorter than 150 cm. Body mass index as a measure of generalized obesity did not significantly predict risk for breast carcinoma. Reproductive and menstrual factors significantly related to risk for breast carcinoma were number of deliveries (OR: 0.81; 95% CI, 0.7-0.9; P < 0.001), age at last delivery (P = 0.03), and use of hormone replacement therapy (OR: 0.54; 95% CI, 0.3-0.9; P = 0.01). Previous breast biopsy for benign disease was also associated with a higher risk for breast carcinoma (OR: 3.5; 95% CI, 2.1-5.7; P < 0.001). CONCLUSIONS: The authors conclude that the risk of breast carcinoma is strongly associated with changes in lifestyle related to caloric intake (central obesity and height) and reproductive or menstrual factors (number of deliveries, age at last delivery, age at menopause, and breast feeding). Better and excess nutrition in early and later years of life and fewer births (related to rapid urbanization) may explain in part the increasing incidence of breast carcinoma occurring in Singapore.

Aged↗
PubMed1997

Serial ultrasound-guided percutaneous liver biopsy in a partial hepatectomy porcine model: a new technique in the study of liver regeneration.

UNLABELLED: Studies on liver regeneration are often carried out on small animal models such as the rat. The use of large animal models however has many advantages. Repeated biopsies of the liver may be carried out and the animal can thus serve as its own control. Sequential changes in the regenerative response to various putative hepatotrophic factors can therefore be studied. Ultrasound-guided percutaneous biopsy (USGPB) of the liver, a technique widely used in clinical practice to obtain liver samples, offers a means for repeated liver biopsies. This study was carried out to validate the use of serial USGPB of the liver as a research technique in the study of liver regeneration in a porcine hepatectomy model. MATERIAL AND METHOD: Left hepatectomy was carried out in nine Yorkshire pigs (20-30 kg). Bromodeoxyuridine (BrdU) at 50 mg/ kg BW was administered daily for the first 5 days after surgery. USGPB was carried out 1 hr later using 16F biopsy needles in a Biopty device. Ultrasonography was carried out using an Acuson XP10 color doppler ultrasound machine. Immunoperoxidase staining of the biopsy specimens was performed using mouse monoclonal antibody to BrdU. Regenerating cells were identified and labeling indices constructed for each day after hepatectomy. All animals were sacrificed at the end of the study and postmortem was performed. RESULTS AND CONCLUSION: USGPB was successful at every attempt and no animal suffered complications following the procedure. Median cumulative labeling indices increased rapidly after hepatectomy and the steepest rise occurred between the third and fourth day after surgery when it increased from 2.25 to 3.40% before leveling off. These results are consistent with those obtained by other reported techniques. USGPB of the liver overcomes the need for repeated laparotomies to obtain biopsy samples in a large animal model and has no morbidity and mortality that could lead to animal wastage.

Animals↗
PubMed1997

Utilization of intraoperative electroneurography to understand the innervation of the trapezius muscle.

The radical neck dissection is an operation for the management of lymph node metastases from primary sites involving the oral cavity, larynx, and other areas of the head and neck. In this procedure, the spinal accessory nerve is removed along with other structures. In modified neck dissection the spinal accessory nerve is preserved. Patients undergoing the modified neck dissection have had variable functional outcomes from little or no pain or disability, to significant muscle dysfunction. Our group hypothesized that patients with good functional outcomes following modified neck dissection may have had motor contributions from C2, C3, or C4 branches, while those with less favorable outcomes did not. To demonstrate the presence of motor input and its significance both from the spinal accessory nerve and the branches of the cervical plexus, we utilized intraoperative electroneurography. We find that although there is motor contribution from C2, C3, and C4 to the trapezius muscle, it was not consistent or significant.

Cervical Plexus↗
PubMed1997

Plasmapheresis in the treatment of inadvertent intravenous infusion of an enteral feeding solution.

This 50-year-old man was on enteral full-strength Ensure through the jejunostomy tube. The enteral feed was accidentally infused through the peripheral intravenous line. He went into a septic state with hypotension, hypoxemia, and increased pulmonary shunting requiring ventilatory and inotropic support. We instituted two cycles of plasmapheresis in an attempt to remove any foreign antigen and toxins present. This resulted in improved oxygenation, rapid recovery, and discharge from intensive care. His blood culture grew Klebsiella species that was consistent with the organism grown from the culture of the Ensure feeds.

Enteral Nutrition↗
PubMed1997

Loss of c-met protooncogene in primary and metastatic sites of breast cancer.

BACKGROUND: It has been proposed that clones of tumor cells acquire higher metastatic potential as a result of specific genetic alterations. This study was designed to determine the role of the c-met protooncogene in systemic spread by comparing the loss of the c-met protooncogene between primary and metastatic breast carcinomas. METHODS: Only patients who had not received chemotherapy or radiotherapy in the preceding 6 months were included in this study. Histologically proven malignant tissue was obtained from the primary tumor, involved nodes, and distant metastatic and recurrent tumors of patients with breast carcinomas. Allelic loss of the c-met protooncogene in tumor tissue was determined by Southern blotting using a polymerase chain reaction-generated 347-bp human met-H probe. Restriction digestion was performed using Taq I and Msp I, with the patient's lymphocyte DNA as controls. RESULTS: Of 52 patients, lymphocyte DNA from 36 patients was heterozygous for the c-met protooncogene (69% informative). Forty-six tumors from these 36 patients were analyzed. Four of 30 primary tumors (13%) showed allelic loss of c-met. Of the nine nodal metastases examined, three (33%) showed allelic loss of the c-met protooncogene. Of seven distant metastatic breast tumors or recurrent disease, two (29%) showed allelic loss (both in patients with skin metastasis in the chest wall). CONCLUSIONS: Allelic loss of the c-met protooncogene was detected in both primary (13%) and metastatic sites (31%) of breast cancer. Although a higher proportion of allelic loss of c-met was noted in nodal and distant/recurrent disease, the difference when compared with the primary tumor was not statistically significant. These findings indicate a limited role of the c-met protooncogene in breast cancer metastases.

Adult↗
PubMed1997

Hypocalcaemia following thyroidectomy for thyrotoxicosis.

BACKGROUND: Temporary postoperative hypocalcaemia is a relatively common complication following thyroidectomy for thyrotoxicosis. Damage, devascularization or inadvertent removal of the parathyroid glands is the most widely accepted reason, but other causes have been postulated including release of calcitonin during operative manipulation and "hungry bone syndrome' due to postoperative reversal of thyrotoxic osteodystrophy. METHODS: The study included 63 patients who had subtotal thyroidectomy, 51 for thyrotoxicosis and 12 for non-toxic goitre. Ninety-two per cent had at least three parathyroid glands preserved. All had postoperative levels of parathyroid hormone measured. RESULTS: The incidence of biochemical hypocalcaemia was 46 per cent and that of symptomatic hypocalcaemia was 21 per cent. No patient was hypoparathyroid. The incidence of hypocalcaemia was 27 of 51 in thyrotoxic patients compared with two of 12 in the non-toxic goitre group (P < 0.05). CONCLUSION: Hypoparathyroidism does not appear to be the main reason for hypocalcaemia after thyroidectomy, and other causes such as "hungry bone syndrome' may be important contributory factors.

Adolescent↗
PubMed1996

Gastric cancers in Singapore: poor prognosis arising from late presentation.

BACKGROUND: Mortality rates from gastric cancer, apart from those derived from Japanese series, remain poor. This paper sought to determine the present outcome of gastric carcinoma in a predominantly Chinese population in Singapore. Prognostic factors useful in predicting survival were also evaluated in this population. METHOD: All cases of histologically confirmed gastric adenocarcinoma presenting in 1992 were entered into a prospective database. Prognostic factors related to age, sex, site of disease, depth of invasion, histological grade, nodal status and stage of disease were evaluated in patients with resectable disease to determine their utility in predicting survival. RESULTS: Of 131 consecutive patients with histologically proven adenocarcinomas, 37% had distant metastases at presentation predominantly in the liver (21%) and peritoneal cavity (20%). Sixty-four per cent of patients underwent surgery and in only 51% of these patients was resection of the tumour possible. Stages III and IV (T4N2) locally advanced disease were present in 38% of patients. Thus the majority of patients presented with late or metastatic disease (75%, stages III and IV). Sixty per cent of patients were alive at 1 year and 40% at 2 years after resection of the tumour (Kaplan-Meier survival plots). In contrast, no patient survived longer than a year if the tumour was not resectable (P < 0.001, log-rank test). Median survival of patients without surgery was 12 weeks. Median survival for patients with resected stage IV disease was 23 weeks, compared to 18 weeks after surgical bypass. Age, sex, site, depth of invasion and histological grade did not significantly predict survival. Patients with node-negative disease survived longer (2 years. 70%) than those with nodal involvement (2 years, 44%: P = 0.06, log-rank test). Pathologic staging with the TNM system was useful in predicting survival (P < 0.001). Sixty per cent of patients with stage I and II disease were alive at 2 years compared to 54% with stage III disease and 0% with stage IV disease. CONCLUSION: The prognosis of stomach cancer remains poor, due predominantly to late presentation. Pathologic TNM staging and nodal status were useful in predicting survival outcome after resection. If the tumour were resectable, survival was appreciable even in patients with advanced stage III (2 years. 54%) and stage IV (1 year, 40%) disease. Strategies to improve outcome should focus on early detection of gastric carcinomas.

Adult↗
PubMed1996

Difficulty of obtaining wide tumour to deep fascial margins in Asian women with breast cancers: implications on treatment and prognosis.

This prospective study sought to determine the width of tumour to fascial margins attainable after mastectomy in Asian women with breast cancers. The narrowest perpendicular distance from tumour to the deep fascia was measured in the mastectomy specimens of 177 consecutive Singaporean women with primary breast carcinomas. A highly significant linear correlation was present between the tumour size (P < 0.001, Pearson's R = -0.34) and the width of deep margins. Furthermore, T staging (P < 0.01, ANOVA) was inversely correlated with the width of deep margins and significant differences were observed between early (T0 to T2) and late (T3 to T4) lesions. In patients with ductal carcinoma in situ (DCIS) and T1 lesions, deep margins greater than 10 mm were achieved in only 23% and 33% of the women respectively. For patients with DCIS, 33% had either positive margins or margins less than 2 mm. The corresponding figures for women with T1 and T2 lesions were 11% and 26%, respectively. The inability to obtain negative deep margins were considerable with large tumours as 10% of the women with T3 tumours and 33% with T4 tumours had positive margins. Thus the proportion of positive or narrow deep margins following mastectomy is appreciable in Asian women and even in those with early tumours. The implications of these findings on the risk of locoregional recurrence or the need for more radical surgery or adjuvant radiotherapy remain uncertain, and will require further elucidation.

Adult↗
PubMed1995

Flexible endoscopic tracheo-oesophageal puncture under local anaesthetic.

Blom-Singer valve prosthesis is an increasingly popular technique for voice rehabilitation in alaryngeal patients. Although primary voice puncture is being practised, the creation of the tracheo-oesophageal fistula is performed in the majority of patients as a secondary procedure. We describe a technique of secondary tracheo-oesophageal puncture using the flexible endoscope which can be performed under local anaesthetic and sedation. The technique overcomes the difficulty of passing a rigid oesophagoscope or forceps to the level of the tracheostome in a scarred and irradiated neck. The new technique also obviates the need for general anaesthesia. We have successfully used the technique in three patients.

Anesthesia, Local↗
PubMed1995

The effect of recombinant growth hormone on nitrogen balance in malnourished patients after major abdominal surgery.

The effect of recombinant growth hormone (rGH) on nitrogen balance was studied in malnourished patients receiving total parenteral nutrition after major abdominal surgery. Fifteen patients were randomized to receive either subcutaneous rGH (0.2 iu/kg) or placebo (saline) injection daily for seven days after surgery. Positive nitrogen balance was achieved throughout the treatment period with rGH administration and was significant on days 3 and 6. This was associated with increase in mid-arm muscle circumference and significant weight gain. Plasma insulin-like growth factor-1 (IGF-1) concentration was significantly raised in the rGH group at day 7, suggesting its role in the anabolic effect of growth hormone. Plasma pre-albumin and retinol-binding protein concentrations were raised in both the rGH and control groups, indicating improvement in the nutritional status. We conclude that the postoperative catabolic response can be attenuated using recombinant growth hormone.

Abdomen↗
PubMed1995

Oropharyngeal reconstruction after ablative surgery of the head and neck--experience of 93 cases.

The surgical defect after radical resection in the head and neck region is extensive and often involves skin, oral mucosa and bone. Primary reconstruction allows for rapid restoration of function and rehabilitation of the patient. We report a series of 93 patients with oropharyngeal reconstruction after ablative surgery in the head and neck. For reconstruction, there were 41 pedicled myocutaneous flaps, 18 random flaps and 7 vascularised free flaps. There were 3 partial and 1 complete flap failures together with 5 persistent fistulas. The factors considered in the choice of reconstruction and our philosophy in this regard are discussed.

Adult↗
PubMed1995

Sexuality of women after mastectomy.

Changes in sexual functioning, attitudes and sexual behaviour in local women after mastectomy and conservative breast surgery for breast cancer were assessed in this study. Given the social bearing, only married women agreed to be entered into the study. The complexities of variables other than breast loss, contributing to sexual difficulties were recognized and assessed. Through questionnaires designed for local women, a significant proportion of mastectomy women were found to have disturbances in at least one area in their sexual functioning after surgery. A significant number experienced changes in their sexual habits as well.

Adult↗