First Report of Dieback Caused by Verticillium dahliae on Blighia sapida in the United States.

Mature akee trees, Blighia sapida K. Koenig, in a local south Florida commercial orchard had wilt and dieback symptoms during spring 1999. A fungus isolated from the gray xylem root tissue on V8 agar was identified as Verticillium dahliae Klebahn at the Division of Plant Industry of the Florida Department of Agriculture and Consumer Services. Twenty akee seedlings were transplanted into 3.85-liter plastic pots and grown in a greenhouse at a daytime temperature of 28°C and nighttime temperature of 23°C. When plants were approximately 25 cm high, a 15-cm knife was used to sever roots in the four quadrants of each pot. Inoculum was made from a 2-week-old culture of V. dahliae on V8 agar and blended with 160 ml of sterile water, and 15 ml of this slurry was poured into the disturbed soil of each of 10 treated plants. A plate of uninoculated V8 agar was applied, as above, to 10 control plants. Plants were kept in the greenhouse. After 6 weeks, inoculated plants showed symptoms of leaf wilt, dieback and plant death. No symptoms were seen on control plants. V. dahliae was isolated directly from the gray vascular tissue of inoculated plants. The inoculation experiment was repeated three times, fulfilling Koch's postulates. To our knowledge, this is the first report of Verticillium dieback on B. sapida in the United States.

Lymphatic mapping improves staging during laparoscopic colectomy for cancer.

BACKGROUND: Recently, lymphatic mapping (LM) of the sentinel lymph node (SN) has been coupled with ultrastaging methods to diagnose nodal micrometastases from colorectal cancer (CRC). We have developed a technique for LM at the time of laparoscopic colon resection (LCR). METHODS: Between August 1996 and February 2000, 11 patients with small early-stage CRC underwent laparoscopic LM and LCR. The primary tumor/polyp site was visualized through a colonoscope and either tattooed preoperatively with a carbon dye (India ink), or stained intraoperatively by peritumoral injection of isosulfan blue dye. Immediately after intraoperative injection of blue dye, efferent lymphatic channels were visualized through the laparoscope and followed to the SN. Each blue-stained SN was marked with a suture or clip. RESULTS: In all 11 cases, laparoscopic LM identified between one and three SN draining the primary tumor. LM added ~15-20 min to the operating time. The SN correctly reflected the nodal status of the entire specimen in all cases. In the one node-positive case, micrometastases were found only in an SN and only after cytokeratin immunohistochemistry (CK-IHC). In four cases, LM demonstrated unexpected primary lymphatic drainage that prompted an increase in the margins of resection. CONCLUSIONS: LM during laparoscopic colectomy for CRC may be useful to mark the primary tumor site and to demonstrate lymphatic drainage that can alter the margins of resection. Focused examination of SN identifies occult micrometastases that up-stage CRC.

Aberrant drainage and missed micrometastases: the value of lymphatic mapping and focused analysis of sentinel lymph nodes in gastrointestinal neoplasms.

Lymph node analysis is essential for staging gastrointestinal (GI) neoplasms. Our group has conducted several studies of intraoperative lymphatic mapping and sentinel lymphadenectomy (LM/SL) for the staging of GI neoplasms. LM is performed following injection of 0.5-1 ml of isosulfan blue dye, and blue-stained sentinel lymph nodes (SLNs) are analyzed by hematoxylin and eosin (H&E) staining, multiple sectioning, and cytokeratin immunohistochemistry. In feasibility trials, LM identified at least one SLN in 121 of 126 patients. Of the 58 cases with nodal metastasis, 50 (89%) had at least one positive SLN and 24 (42%) had nodal metastasis only in the SLN. In 25 cases, tumor deposits were identified by multiple sectioning (n = 8) or immunohistochemistry (n = 17) only. In 10 cases (8%), LM identified aberrant lymphatic drainage that altered the extent of the lymphadenectomy. Our cumulative experience indicates that focused analysis of the SLNs draining GI neoplasms can increase the detection of micrometastases and may improve selection of patients for adjuvant treatment.

Does complete resection of melanoma metastatic to solid intra-abdominal organs improve survival?

BACKGROUND: Patients with distant melanoma metastases have median survivals of 4 to 8 months. Previous studies have demonstrated improved survival after complete resection of pulmonary and hollow viscus gastrointestinal metastases. We hypothesized that patients with metastatic disease to intra-abdominal solid organs might also benefit from complete surgical resection. METHODS: A prospectively acquired database identified patients treated for melanoma metastatic to the liver, pancreas, spleen, adrenal glands, or a combination of these from 1971 to 2000. The primary intervention was complete or incomplete surgical resection of intra-abdominal solid-organ metastases, and the main outcome measure was postoperative overall survival (OS). Disease-free survival (DFS) was a secondary outcome measure. RESULTS: Sixty patients underwent adrenalectomy, hepatectomy, splenectomy, or pancreatectomy. Median OS was significantly improved after complete versus incomplete resections, but median OS after complete resection was not significantly different for single-site versus synchronous multisite metastases. The 5-year survival in the group after complete resection was 24%, whereas in the incomplete resection group, there were no 5-year survivors. Median DFS after complete resection was 15 months. Of note, the 2-year DFS after complete resection was 53% for synchronous multi-site metastases versus 26% for single-site metastases. CONCLUSIONS: In highly selected patients with melanoma metastatic to intra-abdominal solid organs, aggressive attempts at complete surgical resection may improve OS. It is important that the number of metastatic sites does not seem to affect the OS after complete resection.

Diagnostic laparoscopy and laparoscopic ultrasonography optimize the staging and resectability of intraabdominal neoplasms.

BACKGROUND: Despite technical improvements, preoperative imaging studies often fail to predict intraoperative findings. We investigated the potential use of diagnostic laparoscopy (DL) and laparoscopic ultrasonography (LUS) for the assessment of disease in patients with abdominal neoplasms. METHODS: Fifty consecutive patients with abdominal neoplasms underwent spiral computed tomography with oral and intravenous contrast using 5-mm contiguous sections. In addition, eight patients underwent ultrasonography, six underwent magnetic resonance imaging, and eight underwent positron emission tomography. All patients then underwent DL and LUS using a 7.5-MHz ultrasound probe. RESULTS: There were 29 men and 21 women with a mean age of 63 years (range, 35-84). Most had a diagnosis of colorectal cancer (19 cases), melanoma (12 cases), or hepatoma (five cases). In nine cases (18%), DL revealed peritoneal metastatic implants not shown on preoperative images. In 18 cases (36%), LUS was more accurate than preoperative imaging. Combined DL and LUS findings radically changed the operative management in 16 patients (32%). CONCLUSION: As compared with preoperative imaging, the combination of DL and LUS provides more accurate information regarding staging and resectability. Moreover, it helps to determine the extent of operation and reduces the number of unnecessary laparotomies. DL and LUS should be used as an adjunct to preoperative imaging studies in patients with primary or metastatic intraabdominal neoplasms.

Laparoscopic radiofrequency ablation of unresectable hepatic malignancies. A phase 2 trial.

BACKGROUND: Radiofrequency ablation (RFA) of hepatic malignancies has been performed successfully via a percutaneous route or at laparotomy. We analyzed the efficacy and utility of laparoscopic intraoperative ultrasound and RFA in patients with unresectable hepatic malignancies. METHODS: Between November 1997 and November 1999, 27 patients with unresectable hepatic malignancies and no evidence of extrahepatic disease were entered in a phase 2 trial of laparoscopic intraoperative ultrasound and RFA. Real-time ultrasonography was used to guide RFA, and lesions were ablated at a temperature of 100 degrees C for 10 min. Overlapping ablations were performed for larger lesions. RESULTS: Additional tumors were identified in 10 (37%) of the 27 study patients by laparoscopy and laparoscopic intraoperative ultrasound despite extensive preoperative imaging. Radiofrequency ablation of 85 hepatic tumors yielded no mortality and only one case of postoperative bleeding. During a mean follow-up period of 14 months, four tumors (4.7%) locally recurred. Of the 27 patients, 11 (41%) remain free of disease at this writing; (22%) are alive with disease; and 10 (37%) have died with disease. CONCLUSION: Laparoscopic RFA and intraoperative ultrasound constitute a safe and accurate method for ablation of unresectable hepatic tumors.

Long-term management and outcome of parathyroidectomy for sporadic primary multiple-gland disease.

HYPOTHESIS: For a specific subset of patients with sporadic primary multiple-gland parathyroid disease, subtotal parathyroidectomy results in long-term normocalcemia in the majority of patients, with a minimal complication rate. DESIGN: Retrospective analysis of outcomes in patients undergoing parathyroidectomy performed by a single surgeon (A.E.G.) between 1984 and 1999. SETTING: A multidisciplinary endocrine service based at a tertiary referral center. PATIENTS: Patients undergoing subtotal parathyroidectomy for primary hyperparathyroidism due to sporadic multiple-gland disease identified from a single surgeon's operative records (A.E.G.). MAIN OUTCOME MEASURES: Data analyzed included demographic factors, operative and pathologic findings, and postoperative and long-term clinical and laboratory results, including calcium and intact parathyroid hormone levels. RESULTS: Of 379 patients undergoing parathyroidectomy for hyperparathyroidism between 1984 and 1999, 49 (13%) had sporadic multiple-gland disease. Median preoperative calcium and intact parathyroid hormone (iPTH) levels were 2.7 mmol/L (10.8 mg/dL) and 11.79 pmol/L, respectively. Postoperative calcium and iPTH levels were available in 39 patients, and median values were 2.28 mmol/L (9.1 mg/dL) and 2.84 pmol/L, respectively. Long-term follow-up was available for 36 patients (73%), and duration ranged from 6 to 180 months (median, 44 months). Median calcium and iPTH levels at follow-up were 2.3 mmol/L (9.2 mg/dL) and 3.26 pmol/L, respectively, with 3 (8%) of 36 patients having evidence of persistent or recurrent hyperparathyroidism. No patient had biochemical evidence of hypoparathyroidism at long-term follow-up. Five patients (14%) had persistent elevated iPTH levels (range, 8.11-10.95 pmol/L) and normal calcium levels. CONCLUSIONS: Subtotal parathyroidectomy for sporadic primary multiple-gland disease resulted in a long-term normocalcemia rate of 92%, with minimal complications. Selective subtotal parathyroidectomy can yield excellent long-term results in patients with multiple-gland disease.

Validation of lymphatic mapping in colorectal cancer: in vivo, ex vivo, and laparoscopic techniques.

BACKGROUND: The use of lymphatic mapping (LM) is being investigated to improve the staging of colorectal cancer (CRC) and thereby identify patients who might benefit from adjuvant chemotherapy. This study evaluated in vivo, laparoscopic, and ex vivo approaches for the ultrastaging of CRC. METHODS: Seventy-five CRC patients were enrolled in a study of LM with peritumoral injection of isosulfan blue dye. LM was undertaken during open colon resection (OCR) in 64 patients, during laparoscopic colon resection (LCR) in 9 patients, and after specimen removal (ex vivo) in 2 patients. Ex vivo LM was also undertaken in 6 patients after unsuccessful in vivo LM. All nodes were examined by hematoxylin and eosin (H&E) staining; in addition, sentinel lymph nodes (SNs) were multisectioned and examined by immunohistochemical staining with cytokeratin (CK-IHC). RESULTS: At least one SN was identified in 72 patients (96%). In vivo LM identified SNs in 56 of 64 (88%) patients undergoing OCR and in 9 of 9 (100%) patients undergoing LCR. Ex vivo LM was undertaken as the initial mapping procedure in 2 cases of intraperitoneal colon cancer and after in vivo LM had failed in 6 cases of extraperitoneal rectal carcinoma; an SN was identified in 7 of the 8 cases. Focused examination of the SN correctly predicted nodal status in 53 of 56 OCR cases, 9 of 9 LCR cases, and 6 of 7 ex vivo cases. Multiple sections and CK-IHC identified occult micrometastases in 13 patients (17%), representing 10 OCR, 1 LCR, and 2 ex vivo cases. CONCLUSIONS: LM of drainage from a primary CRC can be accurately performed in vivo during OCR or LCR. Ex vivo LM can be applied when in vivo techniques are unsuccessful and may be useful for rectal tumors. During LCR, colonoscopic injection can be used to mark the primary tumor and define the lymphatic drainage so that adequate resection margins are obtained. These LM techniques improve staging accuracy in CRC.

Radiofrequency ablation of unresectable hepatic malignancies: lessons learned.

Radiofrequency ablation (RFA) is increasingly used for the local destruction of unresectable hepatic malignancies. Relative contraindications include tumors in proximity to vital structures that may be injured by RFA and lesions whose size exceeds the ablation capabilities of the probe system employed. Given current technology, we believe that RFA should be cautiously utilized for lesions greater than 5 cm in diameter. Open (celiotomy) and laparoscopic approaches to RFA allow intraoperative ultrasonography, which may demonstrate occult hepatic disease. In addition, RFA performed via celiotomy can be accompanied by resection or cryosurgical ablation, and isolation of the liver from adjacent organs. Percutaneous RFA should be reserved for patients who cannot undergo general anesthesia, those with recurrent or progressive lesions, and those with smaller lesions sufficiently isolated from adjacent organs. Complications may be minimized when these approaches are selectively applied.

Molecular staging of early colon cancer on the basis of sentinel node analysis: a multicenter phase II trial.

PURPOSE: Approximately 30% of patients with American Joint Committee on Cancer stage I or II colorectal cancer (CRC) develop systemic disease. We hypothesized that multimarker reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of sentinel lymph nodes (SNs) draining a primary CRC could detect micrometastases not detected by conventional histopathologic analysis. PATIENTS AND METHODS: In a multi-institutional study, 40 patients with primary CRC underwent dye-directed lymphatic mapping at the time of colon resection. Each dye-stained SN was tagged, and the tumor and regional nodes were resected en bloc. All lymph nodes were examined by conventional hematoxylin and eosin (HE) staining. In addition, each SN was cut into multiple sections for cytokeratin immunohistochemical (CK-IHC) staining and for RT-PCR and electrochemiluminescent detection of three markers: beta-chain human chorionic gonadotropin, hepatocyte growth factor receptor, and universal melanoma-associated antigen. Whenever possible, RT-PCR assay was also performed on primary tumor tissue. The detection sensitivity of individual markers was 10(-3) to 10(-4) microg of RNA and one to five tumor cells in 10(7) lymphocytes of healthy donors. RESULTS: One to three SNs were identified in each patient. An average of 15 nodes were removed from each CRC specimen. No nonsentinel (untagged) node contained evidence of tumor if all tagged (sentinel) nodes in the same specimen were histopathology tumor-negative. HE staining of SNs identified tumor in 10 patients (25%), and CK-IHC of SNs identified occult micrometastases in four patients (10%) whose SNs were negative by HE. Of the remaining 26 patients with no evidence of SN involvement by HE or CK-IHC, 12 (46%) had positive RT-PCR results. The number of markers expressed in each SN correlated (P <.04) with the T stage of the primary tumor. There was 79% concordance in marker expression for the respective pairs (n = 38) of primary tumor and histopathologically positive SNs, and 86% (12 of 14) concordance between RT-PCR positive and histopathologically positive SNs. CONCLUSION: Identification and focused examination of the SN is a novel method of staging CRC. CK-IHC and RT-PCR identified occult micrometastases in 53% of patients whose SNs were negative by conventional staging techniques. These ultrasensitive assays of the SN can identify patients who may be at high risk for recurrence of CRC and therefore are more likely to benefit from systemic adjuvant therapy.

Systemic irinotecan or regional floxuridine chemotherapy prolongs survival after hepatic cryosurgery in patients with metastatic colon cancer refractory to 5-fluorouracil.

Most colorectal cancers metastatic to the liver are resistant to chemotherapy and are not amenable to surgical resection. This study evaluated our 6-year experience (July 1992-July 1998) in treating patients with unresectable hepatic colorectal metastases refractory to systemic 5-fluorouracil (5-FU). One hundred fifty-three patients underwent cryosurgical ablation (CSA) of 5-FU-resistant hepatic metastases. The patients then received either hepatic arterial floxuridine (FUDR), systemic CPT-11, or no postoperative adjuvant chemotherapy. Number, size, and location of hepatic metastases, carcinoembryonic antigen (CEA) levels, and type of postoperative treatment were analyzed. One to 15 lesions were frozen (median number, 3; median size, 6 cm), for a total of 73 synchronous and 80 metachronous lesions. Overall median survival was 28.4 months from the date of diagnosis of liver metastases and 16.1 months from the time of CSA. After cryosurgery alone, median survival was 13 months, which was significantly shorter than the post-CSA survival of 23.6 months with adjuvant CPT-11 and 21.2 months with hepatic FUDR (P = 0.007). Predictors of survival included preoperative CEA, postoperative reduction in CEA, and adjuvant chemotherapy (P < 0.05). Neither size, number of lesions, nor tumor location impacted survival. At a median follow-up of 13 months, 67% of patients have recurred (35% hepatic, 16% extrahepatic, and 49% both). Twenty percent of the recurrences were in the lobe of the CSA site. The 25 patients who underwent a second CSA had a median survival of 28.4 months from CSA and 40 months from the date of diagnosis of liver metastases. These data indicate that CSA offers an effective alternative for unresectable patients resistant to 5-FU. Systemic CPT-11 or regional FUDR may further prolong survival after CSA.

Focused examination of sentinel lymph nodes upstages early colorectal carcinoma.

Approximately 30 per cent of patients with early colorectal carcinoma (CRC) develop systemic disease. A subgroup of these patients may harbor occult micrometastatic disease and might benefit from adjuvant chemotherapy. We investigated sentinel lymph node (SLN) mapping and focused pathologic examination of the SLN as a means of detecting nodal micrometastases. Between 1996 and 2000 SLN mapping was performed in 50 consecutive patients undergoing colectomy for CRC. All lymph nodes in the resection specimen were examined via routine hematoxylin and eosin (H&E) staining. In addition multiple sections of each SLN were examined via both H&E and cytokeratin immunohistochemistry. At least one SLN was identified in 47 patients (94%). In seven patients (14%) SLN mapping identified aberrant drainage that altered the planned resection. The SLN(s) correctly predicted nodal basin status in 44 of 47 (94%) cases; there were three falsely negative SLNs. Sixteen cases had positive SLNs by conventional H&E staining. An additional 10 (20%) cases were upstaged by a focused examination of the SLNs. Micrometastases were identified in three cases by H&E staining of multiple sections of the SLN and in seven only by cytokeratin immunohistochemistry. In nine cases the SLN was the only node containing tumor cells. In this study, SLN mapping demonstrated aberrant nodal drainage patterns that altered the surgical resection in patients with CRC. Focused examination of SLNs may detect micrometastases missed by conventional techniques and thereby identify patients who might benefit from adjuvant therapy.

Radiofrequency ablation of 231 unresectable hepatic tumors: indications, limitations, and complications.

BACKGROUND: Radiofrequency ablation (RFA) is increasingly used for the local destruction of unresectable hepatic malignancies. There is little information on its optimal approach or potential complications. METHODS: Since late 1997, we have undertaken 91 RFA procedures to ablate 231 unresectable primary or metastatic liver tumors in 84 patients. RFA was performed via celiotomy (n = 39), laparoscopy (n = 27), or a percutaneous approach (n = 25). Patients were followed with spiral computed tomographic (CT) scans at 1 to 2 weeks postprocedure and then every 3 months for 2 years. RESULTS: Intraoperative ultrasound (IOUS) detected intrahepatic disease not evident on the preoperative scans of 25 of 66 patients (38%) undergoing RFA via celiotomy or laparoscopy. In 38 of 84 patients (45%), RFA was combined with resection or cryosurgical ablation (CSA), or both. RFA was used to treat an average of 2.8 lesions per patient, and the median size of treated lesions was 2 cm (range, 0.3-9 cm). The average hospital stay was 3.6 days overall (1.8 days for percutaneous and laparoscopic cases). Ten patients underwent a second RFA procedure (sequential ablations) and, in one case, a third RFA procedure for large (one patient), progressive (seven patients), and/or recurrent (three patients) lesions. Seven (8%) patients had complications: one skin burn; one postoperative hemorrhage; two simple hepatic abscesses; one hepatic abscess associated with diaphragmatic heat necrosis following sequential percutaneous ablations of a large lesion; one postoperative myocardial infarction; and one liver failure. There were three deaths, one (1%) of which was directly related to the RFA procedure. Three of the complications, including one RFA-related death, occurred after percutaneous RFA. At a median follow-up of 9 months (range, 1-27 months), 15 patients (18%) had recurrences at an RFA site, and 36 patients (43%) remained clinically free of disease. CONCLUSIONS: Celiotomy or laparoscopic approaches are preferred for RFA because they allow IOUS, which may demonstrate occult hepatic disease. Operative RFA also allows concomitant resection, CSA, or placement of a hepatic artery infusion pump, and isolation of the liver from adjacent organs. Percutaneous RFA should be reserved for patients at high risk for anesthesia, those with recurrent or progressive lesions, and those with smaller lesions sufficiently isolated from adjacent organs. Complications may be minimized when these approaches are applied selectively.

Lymphatic mapping and focused analysis of sentinel lymph nodes upstage gastrointestinal neoplasms.

BACKGROUND: Lymph node analysis is essential for staging gastrointestinal (GI) neoplasms. Intraoperative lymphatic mapping and sentinel lymphadenectomy were originally described for melanoma but have not yet been investigated for most GI neoplasms. HYPOTHESES: (1) Lymphatic mapping and sentinel lymphadenectomy is feasible in GI neoplasms, (2) the sentinel node (SN) status reflects the regional node status, and (3) focused analysis of the SN improves staging accuracy. DESIGN: Prospective patient series. PATIENTS AND METHODS: Lymphatic mapping was performed in 65 patients with GI neoplasms by injecting 0.5 to 1 mL of isosulfan blue dye around the periphery of the neoplasm. Blue-stained SNs were analyzed by hematoxylin-eosin staining, multiple sectioning, and cytokeratin immunohistochemistry. RESULTS: Lymphatic mapping identified at least 1 SN in 62 patients (95%). Of the 36 cases with nodal metastasis, 32 (89%) had at least 1 positive SN and 15 (42%) had nodal metastasis only in the SN. In 11 cases, tumor deposits were identified by multiple sectioning (n = 2) or immunohistochemistry (n = 9) only. In 5 cases (8%), lymphatic mapping identified aberrant lymphatic drainage that altered the extent of the lymphadenectomy. CONCLUSIONS: Lymphatic mapping and sentinel lymphadenectomy are feasible in GI neoplasms and identify aberrant lymphatic drainage. The SN status accurately reflects the regional node status. Focused analysis of the SN increases the detection of micrometastases and may improve selection of patients for adjuvant treatment.

Cryosurgical ablation and radiofrequency ablation for unresectable hepatic malignant neoplasms: a proposed algorithm.

BACKGROUND: Thermal ablation of unresectable hepatic tumors can be achieved by cryosurgical ablation (CSA) or radiofrequency ablation (RFA). The relative advantages and disadvantages of each technique have not yet been determined. HYPOTHESIS: Radiofrequency ablation of malignant hepatic neoplasms can be performed safely, but is currently limited by size. Cryosurgical ablation, while associated with higher morbidity, is more effective for larger unresectable hepatic malignant neoplasms. DESIGN: Retrospective analysis of prospective patient database. PATIENTS AND METHODS: Between July 1992 and September 1999, 308 patients with liver tumors not amenable to curative surgical resection were treated with CSA and/or RFA (percutaneous, laparoscopic, celiotomy). No patient had preoperative evidence of extrahepatic disease. All patients underwent laparoscopy with intraoperative ultrasound if technically possible. Both RFA and CSA were performed under ultrasound guidance. Resection, as an adjunctive procedure, was combined with ablation in certain patients. RESULTS: Laparoscopy identified extrahepatic disease in 12% of patients, and intraoperative hepatic ultrasound identified additional lesions in 33% of patients, despite extensive preoperative imaging. Radiofrequency ablation alone or combined with resection or CSA resulted in reduced blood loss (P<.05), thrombocytopenia (P<.05), and shorter hospital stay compared with CSA alone (P<.05). Median ablation times for lesions greater than 3 cm were 60 minutes with RFA and 15 minutes with CSA (P<.001). Local recurrence rates for lesions greater than 3 cm were also greater with RFA (38% vs 17%). CONCLUSIONS: Laparoscopy and intraoperative ultrasound are essential in staging patients with hepatic malignant neoplasms. Radiofrequency ablation when combined with CSA reduces the morbidity of multiple freezes. Although RFA is safer than CSA and can be performed via different approaches (percutaneously, laparoscopically, or at celiotomy), it is limited by tumor size (<3 cm). Percutaneous RFA should be considered in high-risk patients or those with small local recurrences.

Loss of heterozygosity in squamous cell carcinomas of the head and neck defines a tumor suppressor gene region on 11q13.

Tumor suppressor genes APC, RB1, and DCC, as well as genes localized to 3p and 11q, have been implicated in the development of a number of human tumors. To determine whether allelic deletions occur at these loci in squamous cell carcinomas (SSCs) of the head and neck, 25 primary, 1 metastatic, and 3 recurrent tumors, along with the corresponding constitutional tissues, were analyzed by using a battery of polymorphic DNA markers. For two primary tumors, we also analyzed subsequent metastatic tumors of the lung. Polymerase chain reaction-based restriction fragment length polymorphism studies demonstrated loss of heterozygosity for the APC gene in 2 of 12 (17%), the RB1 gene in 5 of 22 (23%), and the DCC gene in 5 of 13 (38%) informative cases. Alleles on chromosomes 3p, 11q13, and 18q21.1 were lost in 7 of 20 (35%), 9 of 23 (39%), and 4 of 17 (24%) informative cases, respectively. A breakpoint was identified within the chromosomal region 3p13-21.2 in a SCC of the tongue. Breakpoints within 11q13 were identified in 2 additional tumors. Thus, allelic deletions of DCC, 3p, and 11q13 appear to be common in head and neck cancers, suggesting that these genes play a critical and complex role in the development of these tumors. Furthermore, the present study provides definitive evidence for a tumor suppressor gene at chromosome band 11q13 and localizes this gene to the INT2-D11S533 interval for future cloning and sequencing.

Deletion mapping of endocrine tumors localizes a second tumor suppressor gene on chromosome band 11q13.

Multiple endocrine neoplasia type 1 syndrome (MEN1, MIM 131100), an autosomal dominant disease, is characterized by parathyroid hyperplasia, pancreatic endocrine tumors, and pituitary adenomas. These tumors also occur sporadically. Both the familial (MEN1) and the sporadic tumors reveal loss of heterozygosity (LOH) for chromosome band 11q13 sequences. Based on prior linkage and LOH analyses, the MEN1 gene was localized between PYGM and D11S460. Recently, the MEN1 gene (menin) has been cloned from sequences 30-kb distal to PYGM. We performed deletion mapping on 25 endocrine tumors (5 MEN1 and 20 sporadic) by using 21 polymorphic markers on chromosome band 11q13. Of these, two (137C7A, 137C7B) were derived from PYGM-containing BAC (bacterial artificial chromosome-137C7) sequences, one from INT2-containing cosmid sequences and the marker D11S4748, a (CA)20 repeat marker that was developed by us. The LOH analysis shows that the markers close to the MEN1 (menin) gene were not deleted in three of the tumors. These tumors, however, showed LOH for distal markers. Thus, the data suggest the existence of a second tumor suppressor gene on chromosome band 11q13.

A 1.5-megabase physical map encompassing the multiple endocrine neoplasia type-1 (MEN1) locus on chromosome 11q13.

Linkage analysis and loss of heterozygosity studies have shown that the gene responsible for the multiple endocrine neoplasia type-1 (MEN1) syndrome localizes to a small interval between D11S427 and D11S460 on chromosome 11q13. As an initial step to clone this tumor suppressor gene, our group is the first to map the MEN1 region physically using yeast artificial chromosome, bacterial artificial chromosome (BAC), and cosmid contigs. The 1.5-Mb high-resolution, contiguous map extends from PYGM to 300 kb telomeric of D11S460. Of this, the 1.2-Mb interval between PYGM and D11S460 is isolated in cosmids and BACs and will be useful for the development of genomic sequences and transcription maps of this important region. Nine new sequence-tagged sites (STS) are also characterized from this region. The physical map and the STSs will be valuable tools for the cloning of the MEN1 gene.

Streptococcal toxic shock-like syndrome. The importance of surgical intervention.

Pyrogenic exotoxins A, B, and C produced by group A beta-hemolytic streptococci (Streptococcus pyogenes) may cause a syndrome characterized by fever, rash, desquamation, hypotension, and multi-organ-system dysfunction. This syndrome, the streptococcal toxic shock-like syndrome (TSLS), has a rapid and fulminant course closely resembling the staphylococcal toxic shock syndrome (TSS) caused by the staphylococcal toxic shock syndrome toxin-1 (TSST-1). The recent recognition of this syndrome is thought to stem from the appearance of more virulent strains of streptococci that have a greater tendency to produce potent exotoxins than prior strains. During the past 6 years, the authors have treated six patients with TSLS; three of these patients have presented recently. The sites of streptococcal infection associated with the development of the syndrome are frequently in soft tissue and skin. Early diagnosis, treatment with penicillin, and radical operative debridement are required.