Radiation induced small bowel "web" formation is associated with acquired microvascular dysfunction

BACKGROUND AND AIMS

Radiation therapy of abdominal and pelvic solid tumours results in late intestinal toxicity of a severe nature in approximately 5% of cases. These manifestations may include ischaemia and stricture formation, which may present as "webs". These webs are likely to play a role in the pathogenesis of recurrent bowel obstruction. The mechanisms of microvascular injury to the bowel in the setting of radiation have not been defined. We hypothesised that microvascular dysfunction with impaired vasodilation to acetylcholine (Ach) would be an acquired pathophysiological abnormality in radiation and "web" formation.

METHODS

A 40 year old patient treated with radiation, two years previously, for an anal squamous cell cancer presented with recurrent small bowel obstruction. "Webs" in the distal ileum were detected using wireless capsule endoscopy, after small bowel barium radiographs failed to demonstrate a lesion. Following resection, freshly isolated 50-150 mum diameter arterioles from the "web" and adjacent normal calibre bowel were analysed with histology and microvessel physiological studies.

RESULTS

After constriction (30-50%) with endothelin, dilation to graded doses of Ach (10(-9)-10(-4) M) was observed in vessels dissected from the stricture and the adjacent normal calibre area. Ach dilation was reduced in vessels from "web" (mean diameter 7 (2)%; n = 3, p < 0.01) compared with the adjacent unaffected bowel (mean diameter 85 (5)%). Dihydroethidine and dichlorofluorescein diacetate intravital staining demonstrated increased reactive oxygen species production in microvessels from "web" compared with adjacent normal calibre bowel. Histology from the strictured bowel demonstrated narrowing of the arterial lumen due to intimal and muscularis propria fibrosis, with endothelial preservation.

CONCLUSIONS

External radiation is associated with acquired microvascular endothelial dysfunction and "web" formation in the small bowel.

Sinonasal disease in patients with sarcoidosis

Sarcoidosis is a chronic granulomatous disease of unclear etiology with a propensity to involve the lower respiratory tract, but may also involve the upper respiratory tract. Histologically, it is characterized by non-caseating granulomas of various organ systems. Although nasal and sinus involvement is uncommon, patients with sarcoidosis presenting with nasal and sinus complaints may have sinonasal sarcoidosis or simply rhinosinusitis. We reviewed the cases of six patients with pulmonary sarcoidosis who developed chronic sinonasal disease. All six patients had intranasal findings consistent with sinonasal sarcoidosis, but only four had histologic evidence of sinonasal sarcoidosis. These four patients continue to require extensive therapy including topical steroids, systemic steroids, intralesional steroid injections, and nasal irrigations. We conclude that patients with histologically proven sinonasal sarcoidosis present a significant therapeutic challenge because their symptoms and physical findings are often persistent despite aggressive medical and surgical therapy. Their recalcitrant sinonasal disease is thought to result from the destruction of cilia and mucus-producing glands by the granulomatous process.

Immunohistochemistry and molecular detection of nodal micrometastases in pancreatic cancer

PURPOSE

Assays based on polymerase chain reaction (PCR) demonstrate mutated Kiras in the regional nodes of a majority of patients with node-negative stage I or II (T(1-3), N(0), M(0)) pancreatic adenocarcinoma. The hypothesis that the presence of mutated Kiras equates with micrometastases has not been validated by detailed histologic examination nor has an impact on survival been demonstrated.

METHODS

We examined the paraffin blocks of the primary tumor and regional lymph nodes from all 30 patients from 1984 to 1998 with resected pN(0) stage I or II pancreatic adenocarcinoma. DNA was analyzed for mutations in codon 12 of the Kiras oncogene by PCR and restriction digest with BstN1 (RFLP). All nodes were examined by histology of 4 hematoxylin and eosin-stained step sections and immunohistochemistry (HPE/IHC) with AE3/AE1 epithelial cell marker antibody.

RESULTS

Examination of the regional lymph nodes of the 30 patients demonstrated nodal metastases in 9 (30%) by step-section histology alone, 14 (46.7%) by HPE/IHC, 19 (63.3%) by PCR/RFLP, and 25 (83.3%) by a combination of PCR/RFLP and HPE/IHC. Seven cases were HPE/IHC positive yet PCR/RFLP negative while 10 cases were PCR/RFLP positive and HPE/IHC negative. Median survival (months) did not differ if nodes were negative or positive by HPE/IHC (20.5 vs 17.5) or PCR/RFLP (20.0 vs 19.0) or a combination of these techniques (25 vs 18.5).

CONCLUSIONS

A great majority (83.3%) of patients with pathologic stage I or II pancreatic cancer had metastases in their regional nodes. Step-sectioning with immunohistochemistry and PCR/RFLP are complementary tests in detection of metastatic cancer cells. Nodal micrometastases did not adversely influence survival.

p21WAF1 expression is associated with improved survival after adjuvant chemoradiation for pancreatic cancer

BACKGROUND

Cell cycle arrest after DNA damage is partly mediated through the transcriptional activation of p21(WAF1) by the p53 tumor suppressor gene. p21(WAF1) and p53 are both critical in maintaining cell cycle control in response to DNA damage from radiation or chemotherapy. Therefore, we examined the role of p21(WAF1) and p53 in the determination of outcome for patients who receive radiation and/or chemotherapy for pancreatic cancer.

METHODS

p21(WAF1) and p53 protein expression were determined (with the use of immunohistochemistry) in specimens from 90 patients with pancreatic cancer. Forty-four patients underwent surgical resection, and 46 patients had either locally unresectable tumors (n = 9 patients) or distant metastases (n = 37 patients). Seventy-three percent of the patients who underwent resection and 63% of the patients who did not undergo resection received radiation and/or chemotherapy.

RESULTS

p21(WAF1) expression was present in 48 of 86 tumors (56%) and was significantly (P<.05) associated with advanced tumor stage. Median survival among patients with resected pancreatic cancer who received adjuvant chemoradiation with p21(WAF1)-positive tumors was significantly longer than in patients with no p21(WAF1) staining (25 vs. 11 months; P = .01). Fifty of 89 tumors (56%) stained positive for p53 protein. p53 overexpression was associated with decreased survival in patients who did not undergo resection.

CONCLUSIONS

Normal p21(WAF1) expression may be necessary for a beneficial response to current adjuvant chemoradiation protocols for pancreatic cancer. Alternate strategies for adjuvant therapy should be explored for patients with pancreatic cancer who lack functional p21(WAF1).

Predicting metastasis of pheochromocytomas using DNA flow cytometry and immunohistochemical markers of cell proliferation: A positive correlation between MIB-1 staining and malignant tumor behavior

BACKGROUND

In the absence of metastases, there are no reliable microscopic features that distinguish malignant from benign pheochromocytomas. Because a common feature of malignancy is the loss of cell cycle regulation and normal growth arrest, the authors hypothesized that analysis of the cell cycle could be used to aid in the diagnosis of malignant pheochromocytoma.

METHODS

Cell cycle analysis of archival samples of 51 pheochromocytomas (40 sporadic, 11 familial) from 45 patients, including 6 malignant and 45 benign tumors, was conducted. Flow cytometry data and immunohistochemistry for markers of cell proliferation (proliferating cell nuclear antigen [PCNA] and MIB-1 [Ki-67]) were correlated with the authors' clinical data base records, with a mean follow-up of 66 months.

RESULTS

No correlation of DNA ploidy, S-phase fraction by flow cytometry, or PCNA with malignancy was observed. Staining for the MIB-1 nuclear proliferation marker was positive in 3 of 6 (50%) of the malignant pheochromocytomas and negative in all 45 benign tumors (P< 0.01).

CONCLUSIONS

Contrary to some previous reports, a diploid DNA pattern does not necessarily predict benign behavior of pheochromocytoma. In this study, cell cycle analysis and, in particular, assessment of the MIB-1 nuclear proliferation marker was useful in the histologic evaluation of pheochromocytoma, as MIB-1 was expressed only in malignant tumors.

Fine needle aspiration cytology of papillary endothelial hyperplasia. A case report

BACKGROUND

Papillary endothelial hyperplasia is an intravascular or rarely extravascular proliferation of endothelial cells. It is considered an unusual form of thrombus organization.

CASE

A 41-year-old, healthy male presented with a neck mass, which was aspirated. The cytomorphologic features were interpreted as consistent with squamous cell carcinoma. Subsequent workup failed to reveal a primary lesion, and the mass was surgically excised. Histopathology showed papillary endothelial hyperplasia associated with a hematoma. Immunocytochemical staining for factor VIII-related antigen on a destained, alcohol-fixed smear from the fine needle aspirate confirmed the endothelial nature of the cells.

CONCLUSION

A vascular lesion should be considered in a fine needle aspiration biopsy of a head and neck mass, in particular when the clinical features are not consistent with a metastatic malignancy. The absence of cytoplasmic orangeophilia and immunoreactivity for factor VIII-related antigen may be helpful in establishing the diagnosis.

Axillary sentinel lymph node examination in breast carcinoma

OBJECTIVE

To evaluate whether the type of pathologic examination of breast sentinel nodes (frozen section, step sections, and immunoperoxidase staining) results in different percentages of nodes positive for metastatic disease.

DESIGN

Twenty-eight consecutive patients with breast sentinel node biopsies were evaluated by step-sectioning the sentinel node(s) along with performing immunoperoxidase stains for low-molecular-weight cytokeratin and epithelial membrane antigen.

SETTING AND PARTICIPANTS

The patients were from a university hospital and large private hospital.

MAIN OUTCOME MEASURES

The results of the step sections and immunoperoxidase stains were compared with routine examination, that is, intraoperative frozen section along with a single hematoxylin-eosin slide.

RESULTS

Nine cases were positive by routine evaluation, 10 by step sections, and 11 by immunoperoxidase staining.

CONCLUSIONS

The large, multi-institutional studies of sentinel node utility must take into account the surgical pathology methods used to evaluate these specimens so that uniform techniques, which reliably predict the status of the axillary nodes, can be instituted at all institutions that use this procedure.

Hepatocellular carcinoma after renal transplantation in the absence of cirrhosis or viral hepatitis: a case series

The occurrence of hepatocellular carcinoma (HCC) in renal transplant recipients has typically been associated with hepatitis B or C infection. We encountered two cases of HCC in renal transplant recipients with negative hepatitis B and C markers and no underlying liver pathology, in whom immunosuppression therapy consisted of prednisone and azathioprine (AZA). Patient no. 1 is a 66-year-old man with diabetes who underwent cadaveric renal transplantation 13 years before presentation. An ultrasound obtained for evaluation of a prolonged prothrombin time and decreased serum albumin level showed a suspicious nodular lesion in the left lobe of the liver. A computed tomographic (CT) scan confirmed a 4- x 5- x 5-cm mass that, on biopsy, was determined to be well-differentiated HCC. There was no evidence of metastasis, and the results of random biopsies of the surrounding parenchyma were normal. The patient underwent a left lateral segmentectomy, did well, and an initial alpha-fetoprotein (AFP) level of 85995 ng/mL decreased to 9 ng/mL. Approximately 20 months postoperatively, however, a surveillance CT scan showed three hypervascular lesions in the right lobe of the liver and the AFP level increased to 28,370 ng/mL. Subsequent percutaneous alcohol injections yielded good results, and the patient is alive and well 13 months later. Patient no. 2 is a 57-year-old man who underwent cadaveric renal transplantation 24 years earlier. A CT scan of the abdomen obtained for evaluation of lower abdominal pain showed a 4- x 4- x 6.5-cm mass in the right lobe of the liver that, on biopsy, was found to be poorly differentiated HCC. Multiple biopsies of adjacent liver parenchyma showed no evidence of cirrhosis, AFP level was normal, and imaging studies showed no evidence of tumor spread. The patient underwent a right hepatic lobectomy and is doing well without evidence of recurrence 27 months postoperatively. Our two patients had no evidence of viral hepatitis, cirrhosis, or metabolic liver disease, yet both developed HCC. The use of AZA may have had a role in the development of HCC. In renal transplant recipients on long-term immunosuppression therapy, particularly AZA, it is prudent to maintain a high index of suspicion for HCC when liver enzyme level or function abnormalities are encountered.

Adenocarcinoma of the pancreas: detection of occult metastases in regional lymph nodes by a polymerase chain reaction-based assay

BACKGROUND

Stage I (T1-2NOM0) adenocarcinoma of the pancreas is associated with a 5-year survival rate of 15-25%. Despite apparently curative resection and pathologic staging indicating localized disease, these cancers recur. The authors hypothesized that there exists microscopic regional disease that is not detected by surgical exploration or routine histopathology.

METHODS

Because 90-95% of pancreatic cancers exhibit codon 12 K-ras mutations, the authors examined regional lymph nodes for mutated K-ras as a marker of metastasis. DNA was extracted from paraffin embedded archival specimens (primary tumors and histologically negative lymph nodes) of patients with Stage I pancreatic adenocarcinoma. The target region of K-ras was amplified by polymerase chain reaction (PCR) and tested for codon 12 mutation by BstN1 restriction digestion (restriction fragment length polymorphism [RFLP]) that recognized normal but not mutated sequences. Cell lines that harbored normal or mutated K-ras and resected jejunum or gallbladder were used as controls. The regional lymph nodes of 22 patients whose tumors harbored mutated K-ras were tested.

RESULTS

Dilution experiments with normal and mutant control cell line DNA demonstrated an assay sensitivity for mutated K-ras of 0.1%. Mutated K-ras was found in at least 1 regional lymph node in 16 (73%) of 22 patients with pathologic Stage I pancreatic adenocarcinoma, which suggested metastases not detected by routine histopathology. DNA sequence analysis was performed in four patients and confirmed identical point mutations in the primary tumor and accompanying PCR/RFLP positive lymph nodes.

CONCLUSIONS

Pathologic examination of regional lymph nodes in pancreatic adenocarcinoma specimens fails to detect metastases in many patients. Lymph node micrometastasis is one reason for the poor survival rates observed among patients with Stage I cancers. PCR/RFLP may have a role in staging early pancreatic cancers.

Molecular metastases in stage I pancreatic cancer: improved survival with adjuvant chemoradiation

BACKGROUND

Reports of improved survival rates for patients with resected adenocarcinoma of the pancreas coincide with the adoption of adjuvant chemoradiation protocols. The impact of nodal micrometastases demonstrated by molecular assays and adjuvant therapy on survival of patients with stage I pancreatic cancer has not been adequately assessed.

METHODS

A retrospective analysis of postoperative chemoradiation on survival in 61 patients undergoing resection of pancreatic adenocarcinomas from 1984 to 1997 was performed. Archival tumors and regional nodes from 25 patients with stage I cancers were tested for a Kiras oncogene mutation using polymerase chain reaction and analysis for restriction fragment length polymorphisms (PCR/RFLP).

RESULTS

Adjuvant chemoradiation was associated with improved survival for stage I (P < .01), but not stage III, disease. Seventeen (68%) of 25 patients with stage I disease tested had evidence of mutant Kiras in one or more regional nodes. Survival did not differ for patients with molecular micrometastases. Six of 17 (35%) patients with micrometastases received adjuvant chemoradiation and had improved survival (P < .05).

CONCLUSIONS

The majority of patients with stage I pancreatic cancer have PCR/RFLP evidence of lymph node micrometastases. Adjuvant chemoradiation improves survival in these patients by treating micrometastases not detected by histology. Adjuvant chemoradiation should be used for patients with stage I pancreatic cancers.

Asphyxial death caused by a laryngeal schwannoma: a case report

Neurogenic tumours of the larynx are unusual, with approximately 115 cases reported in the literature to date. Most of these lesions are benign, solitary submucosal nodules which present with hoarseness and are amenable to surgical resection. We present a case of a large pedunculated schwannoma arising in the aryepiglottic fold associated with sudden asphyxial death in an otherwise healthy young female.

Barrett's ulcer: the clinical significance today

OBJECTIVES

The present day clinical significance and natural history of Barrett's esophageal ulcer are compared with those reported originally by Barrett.

METHODS

Records of patients with Barrett's ulcers followed by the Gastroenterology Service at the Medical College of Wisconsin were reviewed to assess the natural history of the ulcers in patients with Barrett's esophagus.

RESULTS

The histories of 14 patients with ulcers in Barrett's esophagus were reviewed. Average follow-up was 5 yr. Ulcers occurred in both short and long segment Barrett's and responded poorly to therapy. Dysplasia occurred in eight patients, and carcinoma developed in two.

CONCLUSIONS

Barrett's ulcers occur today and are difficult to manage, as they were 45 yr ago. Complications today, especially dysplasia and carcinoma, are different than those reported by Barrett (life-threatening hemorrhage, esophageal perforation, and stenosis.)

Nongranulomatous chronic idiopathic enterocolitis: clinicopathologic profile and response to corticosteroids

BACKGROUND & AIMS

Nongranulomatous ulcerative enterocolitis has been reported in association with celiac sprue, lymphoma, and hypogammaglobulinemia. The objective of this study is to present evidence that this disorder exists as a primary entity.

METHODS

The medical records and histological material of 9 patients (mean age, 45.7 +/- 5.9 years) who presented with severe chronic diarrhea without specific diagnosis after extensive investigations were reviewed.

RESULTS

Endoscopically, the duodenum and proximal jejunum were inflamed in 6 of 7 patients, with superficial ulcerations in 5 patients. On histology, the lamina propria was infiltrated by polymorphonuclear and chronic inflammatory cells, with varying degrees of villous atrophy. There were no significant cellular abnormalities of the epithelial enterocytes. A similar inflammatory infiltrate was present in the colon in 4 or 5 patients. Eight of 9 patients responded to corticosteroids with clinical and variable histological improvement. Four patients developed bleeding from ulcerations in the small or large intestine. Three patients died: 1 patient who did not respond to treatment with corticosteroids and 2 patients with systemic infection. Four of the 6 surviving patients required maintenance low-dose corticosteroid therapy. No underlying disease was discovered during prolonged follow-up.

CONCLUSIONS

Idiopathic nongranulomatous enterocolitis may present as a primary, frequently fatal disease. Corticosteroid therapy provides immediate benefit and may be required indefinitely.

Gip-2 codon 179 oncogene mutations: absent in adrenal cortical tumors

The role of G protein mutations in the pathogenesis of adrenal cortex neoplasms is controversial. Two published studies disagree on the existence of a cysteine or histidine for arginine substitution at position 179 (R179C/H) of the GTP binding region of the alpha chain of an inhibitory G protein (Gi2alpha) in these tumors. Prior studies using detection by mutation-specific oligonucleotide hybridization showed either 3 of 11 or 0 of 56 tumors harbored mutations. To resolve this discrepancy and ascertain the importance of the R179C/H Gi2alpha mutation in the development of adrenal cortex tumors, we screened tumors from 29 patients (24 with adenoma, 5 with carcinoma) using a more sensitive assay employing polymerase chain reaction (PCR) and examination for restriction fragment length polymorphisms (RFLP). Detection of the potential R179C/H mutation by this technique was possible because the wild-type coding sequence includes the BSTU-1 restriction endonuclease recognition site CGCG, whereas the mutated gene does not. Results showed complete digestion of the amplified DNA samples from all 29 patients and the negative control DNA by BSTU-1, indicating that all tumor samples exhibited only the wild-type sequence. Direct sequencing of PCR product from four tumor samples confirmed the presence of only the wild-type sequence. The 0 of 29 rate of R179C/H mutations we found in Gi2alpha is different than the 3 of 11 positive rate (p < 0.05, Fishers' exact) previously reported but agrees with the report showing 0 of 56 mutations. We conclude a mutation at position 179 of Gi2alpha is not important in the pathogenesis of most adrenal cortical tumors.

Metaplastic breast carcinoma invading chest wall

Metaplastic breast carcinoma refers to a heterogeneous group of neoplasms in which the typical glandular growth pattern of the tumor undergoes metaplasia, either epithelial or stromal. A 59-year-old woman presented with a breast mass that recurred in 1 year and showed invasion of the chest wall. Histological sections of both the tumor and the recurrence showed a tumor composed predominantly of stromal spindle cells with neoplastic epithelial ducts. Squamous metaplasia was seen in some ducts. Immunohistochemical staining showed positive cytokeratin and epithelial membrane antigen staining of the epithelial cells. Smooth muscle actin, S100, and vimentin were diffusely positive in the stromal cells. Electron microscopy of the original lesion showed cells with squamous epithelial and smooth muscle characteristics, and other cells that formed lumens into which microvilli projected. Electron microscopy of the recurrent lesion showed primarily spindle-shaped cells with abundant tonofilaments in the perinuclear cytoplasm, desmosomes with associated tonofilaments, filaments with focal densities, often aligned parallel with the cell membranes, surface attachment plaques, and fragments of basement membrane. Pinocytotic vesicles were rare. These metaplastic cells are derived from myoepithelial cells which are multipotential and able to differentiate into epithelial or stromal cells.

Noninfectious inflammatory response to gold weight eyelid implants

We describe three patients with noninfectious inflammatory reactions to gold weight eyelid implants, a complication not previously reported. Eyelid edema and erythema developed gradually in each patient, and maximal inflammation that prompted treatment was present at 12, 3, and 5 weeks, respectively, after surgery in the three patients. Management involved removal of the implant in the first patient, oral corticosteroids followed by replacement of the implant by a platinum weight in the second patient, and a local corticosteroid injection with retention of the implant in the third. Histopathological features included a thick eosinophilic coagulum at the tissue-gold interface and an intense, predominantly lymphocytic infiltrate in the collagenous capsule that surrounded the implants. Gold weight eyelid implants can elicit a gradually progressive inflammatory response. In at least some cases, local corticosteroid injection may suppress the inflammation and permit retention of the implant.

Primary squamous cell carcinoma of the breast: sensitivity to cisplatinum-based chemotherapy

Primary squamous cell carcinoma (SCC) of the breast is a rare malignancy whose optimal treatment and prognosis are unknown. A patient with SCC whose tumor responded dramatically to chemotherapy as part of multimodal treatment is presented. A 61-year-old woman had a palpable 5.5-cm tender left breast mass with overlying skin edema and erythema and irregular margins by mammography. Fine needle aspiration revealed malignant squamous cells with keratinization; incisional biopsy confirmed SCC. Extensive evaluation for an extramammary primary site of disease was negative. Neoadjuvant cisplatinum and 5-fluorouracil (5-FU) led to tumor shrinkage and complete resolution of pain and erythema. Modified radical mastectomy with post-operative chest wall radiation were performed. Neither residual invasive carcinoma nor metastatic nodal disease was found, though intraductal carcinoma with marked squamous features was identified. The patient remains disease-free 2.5 years after diagnosis. Cisplatinum-based chemotherapy should be considered in the treatment regimen of this disease.

Increased signal in the normal supraspinatus tendon on MR imaging: diagnostic pitfall caused by the magic-angle effect

OBJECTIVE

Increased signal intensity within the distal portion of the supraspinatus tendon during MR imaging is a frequent observation even in healthy subjects. This finding has been variously attributed to the presence of fat, muscle, connective tissue, abnormal vascularity, or degenerative changes. More recently, the effect of tendon orientation in the static magnetic field (Bo) has been implicated. It has been shown that tendons at the magic angle of 55 degrees to Bo show markedly increased signal. This study was designed to determine the contribution of the magic-angle effect to the MR signal in the distal portion of the supraspinatus tendon.

SUBJECTS AND METHODS

Five healthy volunteers were imaged in a 1.5-T unit using short TR/TE sequences in standard supine position; they were then reimaged laterally flexed at the waist to reorient the plane of the distal portion of the supraspinatus tendon by approximately 20 degrees relative to Bo. In the second part of the study, three cadaveric shoulders were similarly imaged, first in standard position and then reoriented approximately 35 degrees by simple rotation of the specimen. The supraspinatus tendon was evaluated in each subject by noting the length of the segment with increased signal and the position of this segment relative to the insertion of the tendon on the greater tuberosity. Comparisons were made for each live and cadaveric subject between neutral and rotated positions.

RESULTS

Segments of increased signal changed in length and position for each live and cadaveric subject from the neutral to the reoriented position.

CONCLUSION

Our study suggests that tendon orientation contributes significantly to the presence of increased signal within the supraspinatus tendon, as caused by the magic-angle effect. Failure to recognize this effect may lead to diagnostic inaccuracy when evaluating the rotator cuff on short TR/TE sequences.

Pyoderma fistulans sinifica (fox den disease): a distinctive soft-tissue infection

Pyoderma fistulans sinifica (PFS, also referred to as fox den disease because its multiple fistulae and sinuses resemble the structure of a fox den) is a distinct chronic infectious disease in which epithelialized tracts form within the subdermal fatty tissue. PFS, which has not been previously described in the English-language literature, must be differentiated from hidradenitis suppurativa, pilonidal sinus, and perianal fistula. The fistulous tracts of PFS are always lined by stratified squamous-cell epithelium but, unlike those of hidradenitis, reach deep into the subcutaneous fat, run epifascially for long distances, and have no relation to skin appendices. We report on 10 men (mean age +/- SD, 36 +/- 5 years) with PFS (mean duration +/- SD, 11 +/- 7 years). Bacterial cultures of affected tissue from these patients yielded a total of 14 facultative and 31 obligate anaerobic species. Treatment consisted of wide en-bloc excision down to the fascia, including all fistulae. Antibiotic therapy temporarily reduced purulent discharge but did not eradicate the infection. Two patients who underwent fistulotomy without wide en-bloc excision developed recurrences.

Tissue humoral response to intact and ruptured silicone gel-filled prostheses

Biopsies of the fibrous capsule in 31 women undergoing explanation of gel-filled breast prostheses and in 3 women with silicone gel-associated granulomas were tested for the presence of IgG, IgM, IgA, C3 complement, and fibrin using fluorescent antisera. Of a total of 41 prostheses removed, 9 were found to be ruptured but contained within the fibrous capsule or immediately adjacent to it. In the 3 women undergoing granuloma excision only, the sites were the arm (2) and the chest/axilla (1). In one patient, IgG, C3, and fibrin were detected in the capsule of an intact prosthesis. C3 and fibrin were present in the capsule surrounding one ruptured prosthesis. Fibrin was detected in the capsule of one other patient. Bilateral capsules surrounding intact prostheses removed from 4 patients with collage-vascular diseases were negative for C3, fibrin, and immunoglobulins, as were the 3 granulomas from distant sites. Hematoxylin and eosin stains revealed a typical foreign-body response to gel in almost all cases. Both T- and B-cell lymphocytes are present in the infiltrate surrounding silicone gel. In this study, chronic exposure to silicone gel-filled prostheses did not result in antibody deposition or complement activation in the fibrous capsule or in the tissue surrounding gel droplets.

Focal masses in cirrhotic liver: CT and MR imaging features

The development of hepatic cirrhosis triggers attempted repair through regenerative nodules of parenchyma among bands of scar tissue. Some authors believe that this regeneration initiates an evolutionary process that may lead to nodular enlargement and cellular dedifferentiation to malignancy. Both the destructive and reparative processes in cirrhosis produce changes that the radiologist must recognize when imaging the cirrhotic liver. This essay describes the CT and MR features of masses and masslike lesions in the cirrhotic liver, including the identifying characteristics and overlapping appearances of CT and MR.

Hydroxyethyl starch deferoxamine, a novel iron chelator, delays diabetes in BB rats

Hydroxyl radicals (.OH) may contribute to beta cell death. Because iron catalyzes .OH production, we examined whether administration of a novel, long-acting iron chelator, hydroxyethyl starch-deferoxamine (HES-DFO) could prevent diabetes in spontaneously diabetic biobreeding (BB) rats. In our colony, a peripheral lymphocyte count (PBLC) < 4200 mm3 has an 88% positive predictive value for onset of diabetes mellitus (DM). Rats with PBLC < 4200 mm3 were randomized at 6 weeks of age to receive 50 mg/kg of HES-DFO (a high molecular weight hydroxyethyl starch-conjugated derivative of deferoxamine) or equimolar hydroxyethyl starch (HES) alone given intraperitoneally three times weekly until DM or 120 days of age. Administration of HES significantly decreased the incidence of IDDM to 57% as compared with the incidence of 87% in the lymphopenic unmanipulated BB rats in the colony (p < 0.01). Administration of HES-DFO further significantly decreased the incidence of IDDM to 31% as compared with the lymphopenic unmanipulated rats (p < 0.01). When analyzed by sex, 3 of 17 (18%) HES-DFO-treated males developed DM, versus 10 of 17 (58%) of HES-treated males (p < 0.05, chi square); 8 of 19 (42%) of HES-DFO-treated females developed DM, versus 11 of 20 (55%) HES-treated females (p = NS). There were no differences between the groups in (1) mean time of onset of DM, (2) serum iron levels at study entry and completion, (3) weekly hematocrits, (4) total lymphocyte counts; and (5) weekly weight gains.(ABSTRACT TRUNCATED AT 250 WORDS)

Wound healing of KTP and argon laser lesions in the canine nasal cavity

The potassium titanyl phosphate (KTP) and argon lasers are increasingly used in nasal and sinus surgery. Histologic effects of these lasers on living nasal tissue have not been investigated. Sixteen dogs underwent laser nasal surgery (eight for each laser). Flexible fiberoptic quartz fibers were used with both lasers to deliver the laser energy to the tissue. The dogs were allowed to heal and then underwent biopsy at 3, 7, 21, and 90 days postoperatively. The argon and KTP lasers had similar tissue effects. Histologically, a thin rim of coagulation necrosis and acute inflammation were seen at 3 days postoperatively. By 7 days, fibroblasts and granulation tissue were observed. At 21 days, fibroblast proliferation and re-epithelialization with respiratory epithelium were the predominant findings. Finally, at 90 days postoperatively, respiratory epithelium and submucosal structures were found overlying a plug of scar filling the defect in the septal cartilage. This healing was consistent through a wide range of energy densities. These lasers are easily used with sinus endoscopes and the operating microscope to allow access to difficult areas. These factors and the wound-healing characteristics noted in this study would seem to make them suited for use in rhinologic surgery.

Short-term effect of silicone gel on peripheral nerves: a histologic study

The effect of silicone gel on the peripheral nerve was studied in Sprague-Dawley rats. Silicone gel was placed either extraneurally (N = 36) adjacent to or injected directly in the sciatic nerve (N = 20). Nerve histology was studied every 2 weeks over a 20-week period. Extraneural silicone gel elicited an intense inflammatory response characterized initially by predominantly histiocytes with a few eosinophils, lymphocytes, and foreign-body giant cells. The cellular response peaked at 4 weeks, after which time collagen deposition increased and the thickness of the cellular infiltrate surrounding the gel decreased. The gel was temporarily contained by the inflammatory response, but throughout the time course of the study, gel migration and breakup into smaller droplets occurred. Each droplet appeared to initiate the inflammation-fibrosis cycle anew. Perineural fibrosis was marked by 20 weeks, but there was no penetration of the epineurium by the gel. Intraneurally injected silicone gel also caused a delayed, but similar inflammatory response, eventually followed by fibrosis surrounding the gel. Intraneural gel tended to remain in larger droplets and did not migrate over the duration of this study. No direct evidence of gel toxicity to peripheral nerves was observed in either the extraneural or intraneural gel groups despite the initial intense inflammatory response and subsequent fibrosis.

Assessment of ampulla of Vater pathology. An endoscopic approach

One hundred eighty-nine endoscopic biopsies of the papilla of Vater were obtained from 125 patients during a 10-year period. Chronic inflammation was the most common histologic change identified. Of the 44 patients with papillary neoplasia, 42 were diagnosed by endoscopic biopsy. Sixteen of the 18 patients with invasive carcinoma were diagnosed by biopsy. Follow-up biopsies in patients endoscopically managed demonstrated recurrent tumors in 6 of 11 patients. With advances in instrumentation and techniques, pathologists can expect to see increasing numbers of ampullary biopsies. When multiple biopsy fragments are obtained and step sectioned, the diagnostic reliability of endoscopic biopsies in patients with tumors and carcinoma is greater than 90%. The morphologic spectrum of papillary lesions is similar to that seen in the colon with some significant exceptions. Tumor morphology varied considerably from area to area. Variations were seen in the basic architecture (villous-tubular), grade of dysplasia, presence of malignancy, and invasion from fragment to fragment, and in some cases from microscopic field to field. Another notable difference between the ampulla and colon is the rich mucosal lymphatic network of the ampullary region. Thus, any carcinoma invading the lamina propria was diagnosed as invasive carcinoma.

Hyperplastic gastropathy. Clinicopathologic correlation

Assessment of gastric histology in patients with hyperplastic gastritis is now possible using new endoscopic biopsy techniques that obtain a full-thickness gastric mucosal biopsy. Thirty-one patients with hyperplastic gastropathy and full-thickness gastric mucosal biopsies or gastric resections were seen during a 13-year period. Six patients had Zollinger-Ellison syndrome (ZE) with gastric gland hyperplasia; six had Menetrier's disease with foveolar hyperplasia and gland atrophy; and a single patient with hyperplastic hypersecretory gastropathy (HHG) was seen. The majority of patients, 18 of 31 with large folds, had peptic disease. The enlarged gastric folds were due to edema and inflammation. Discordant clinical findings and gastric pathology were seen in four patients: three of the 18 patients with peptic disease had histology typical of ZE (two patients) or Menetrier's disease. None of the three patients have developed a syndrome on follow-up ranging up to 5 years. Also, the patient with HHG had the gastric histology seen in Menetrier's disease. One patient with Menetrier's disease had areas of atrophic gastritis interspersed between the hyperplastic gastritis. In summary, the majority of patients with endoscopic hyperplastic gastropathy had gastritis on histologic examination. Most patients with a clinical syndrome associated with hyperplastic gastritis showed histology typical for the syndrome; however, clinical-histologic concordance was not absolute. In a small minority of cases, a patient with one clinical syndrome had the histology typical of another.

Ampullary hamartoma: endoscopic diagnosis and treatment

This study shows a patient who presented with intermittent biliary tract obstruction caused by ampullary hamartoma. Endoscopic retrograde cholangiopancreatography showed a large ulcerated papilla and dilated biliary ducts. Tissue diagnosis was established by a large particle biopsy obtained with a snare. The patient underwent a successful endoscopic sphincterotomy and has remained symptom free for 4 years.

Role of ultrasonic tissue characterization to distinguish reversible from irreversible myocardial injury

Tissue characterization reflects structural and functional integrity of tissues. Inasmuch as reversible ischemia causes no structural damage and irreversible ischemia results in persistent structural myocardial damage, we postulated that ultrasonic tissue characterization can distinguish the two types of injuries. Anesthetized open chest dogs underwent 15 minutes (group 1, n = 5) and 90 minutes (group 2, n = 8) of acute total occlusion of the left anterior descending coronary artery, followed by 3 hours of reperfusion. Myocardial ischemia-infarction was confirmed with segment shortening, electronmicroscopic examination, and triphenyl tetrazolium chloride staining. Integrated backscatter Rayleigh 5 (IBR5), a measure of ultrasonic backscatter, and Fourier coefficient of amplitude modulation (FAM), an index of cardiac cycle dependent variation in backscatter, were measured at baseline, during ischemia, and after reperfusion. Group 1 (reversible ischemia) showed an increase in IBR5 from -48 +/- 1.2 dB at control to -45 +/- 1.0 dB (p less than 0.01) during ischemia, which returned to baseline after reperfusion (-47 +/- 1.3 dB). FAM was blunted during ischemia (6.2 +/- 1.0 dB during control versus 1.2 +/- 1.0 dB during ischemia, p less than 0.01) and recovered completely during reperfusion. Segment shortening was abolished during ischemia (18% +/- 3% during control versus -12% +/- 5% during ischemia, p less than 0.01) and recovered partially during reperfusion (4% +/- 5%). The group 2 animals with irreversible myocardial injury showed an increase in IBR5, from -49 +/- 1.2 dB during control to -44 +/- 1.0 dB during ischemia (p less than 0.01) and paradoxical bulging of the ischemic region (17% +/- 3% to -7% +/- 3%, p less than 0.01) during ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitative ultrasonic assessment of normal and ischaemic myocardium with an acoustic microscope: relationship to integrated backscatter

PURPOSE OF INVESTIGATION

The aim was to study ultrasonic propagation properties of normal and ischaemic myocardium with a scanning laser acoustic microscope and to correlate these changes with ultrasonic backscatter.

DESIGN

Myocardial ischaemia was produced by total occlusion of left anterior descending coronary artery in anaesthetised open chest dogs. Myocardium supplied by left circumflex coronary artery served as normal control. IBR5, an optimum weighted frequency average (4-6.8 MHz) of the squared envelope of diffraction corrected backscatter, was measured in vivo. Ultrasonic attenuation coefficient, an index of loss per unit distance, the propagation speed and heterogeneity index were measured from normal and ischaemic regions with a scanning laser acoustic microscope which operates at 100MHz in vitro. Myocardial water content of normal and ischaemic myocardium was also estimated.

SUBJECTS

Were five anaesthetised mongrel dogs.

RESULTS

Attenuation coefficient of 33.8(SD4.2) dB.mm-1 in the ischaemic tissue was lower than 63.8(17.2) dB.mm-1 in the normal tissue (p less than 0.01). Ultrasonic speed was lower in ischaemic than normal myocardium at 1584(25) v 1612(35) m.s-1 (p less than 0.05). Heterogeneity index of 11(7) m.s-1 in the ischaemic region was lower than 14(8) m.s-1 in the normal region (27% reduction, p less than 0.05). IBR5 and myocardial water content were higher in the ischaemic than the normal myocardium: -37.2(SEM1.8) dB v -46.6(0.6) dB, (p less than 0.01) and 80.9(0.0)% v 78(0.2)%, (p less than 0.05) respectively.

CONCLUSION

Ultrasonic properties of the myocardium are significantly altered during acute ischaemia.

Histologic spectrum of diversion colitis

Biopsy specimens taken from six patients with diversion colitis, an inflammatory process that occurs in the bypassed colonic segment after diversion of the fecal stream, showed a spectrum of histologic changes ranging from mild colitis to those seen in severe active chronic ulcerative colitis. Histologic abnormalities included aphthous ulcers, crypt distortion, atrophy and abscesses, a villous colonic surface, and a mixed acute and chronic inflammatory infiltrate with patchy lymphoid hyperplasia. Accurate pathologic diagnosis is dependent on clinical history, comparison of histologic morphology in both colonic segments, and response to therapy with local application of short chain fatty acids.

Treatment of diversion colitis with short-chain-fatty acid irrigation

A condition known as diversion colitis frequently develops in segments of the colorectum after surgical diversion of the fecal stream; it persists indefinitely unless the excluded segment is reanastomosed. The disease is characterized by bleeding from inflamed colonic mucosa that mimics the bleeding of idiopathic inflammatory bowel disease, and it may culminate in stricture formation. We hypothesized that this condition is caused by the absence of luminal short-chain fatty acids, the preferred metabolic substrates of colonic epithelium. We studied four patients with diversion colitis, none of whom had evidence of Crohn's, idiopathic ulcerative, or infectious colitis. The excluded segment of the rectosigmoid contained negligible concentrations of short-chain fatty acids. When D-glucose was instilled, it did not undergo appreciable anaerobic fermentation. Instillation of a solution containing short-chain fatty acids twice daily resulted in the disappearance of symptoms and the inflammatory changes observed at endoscopy, over a period of four to six weeks. Remission has been maintained for up to 14 months (in one patient) by instillation daily to twice weekly. Administering enemas containing isotonic saline, or omitting treatment for periods of two to four weeks during the regimen, by contrast, did not produce any improvement or rapid relapse of the colitis. Histologic observation revealed a distinctive type of mucosal inflammation that resolved more slowly and less completely than the gross appearance of the inflamed mucosa. From these preliminary studies we infer that diversion colitis may represent an inflammatory state resulting from a nutritional deficiency in the lumen of the colonic epithelium, which is effectively treated by local application of short-chain fatty acids, the missing nutrients.

Porokeratosis of mibelli in transplant recipients

Four of 602 renal and hepatic transplant recipients had porokeratosis of Mibelli develop in the posttransplant period. Porokeratosis is an uncommon, autosomally dominant inherited disorder that presents in adolescence as a proliferation of an abnormal clone of epidermal cells. Clinically, it is characterized by nonhealing plaques that develop most commonly on the limbs. Porokeratosis, a premalignant condition, must be added to the list of potential cutaneous complications seen in immunosuppressed organ transplant recipients.

DNA content in radiation-associated thyroid cancer

DNA content has been reported to be of prognostic significance in differentiated thyroid carcinoma. Since malignant tumors with irradiation as an initiator often contain DNA aberrations, the DNA content of well-differentiated thyroid carcinoma in patients with a prior history of low-dose head and neck irradiation was determined and compared with similar nonradiation-associated lesions. The DNA content of thyroid cancers from 53 patients was determined with use of flow cytometry. Sixteen radiation-associated thyroid carcinomas (11 papillary, 3 follicular, and 2 medullary) all were diploid. In a group of 37 nonradiation-associated tumors, 10 were aneuploid (10 of 29 papillary carcinomas and 0 of 2 follicular or 6 medullary carcinomas). This difference in DNA content is significant (p less than 0.02, Fisher's exact test). These findings were unexpected and suggest that if the initiating irradiation causes a DNA aberration, this aberration is not reflected in DNA content as measured by means of flow cytometry.

Control mechanisms of sphincter of Oddi contraction rate in the opossum

Our aim in this study is to determine whether extrinsic autonomic nerves regulated spike-burst rate in the opossum sphincter of Oddi (SO) during fasting or after feeding. We implanted electrodes on the distal SO, proximal SO, gastric antrum, duodenum, and jejunum of 20 animals. A cut transection and reanastomosis was done at different levels of the SO to interrupt putative extrinsic or intrinsic nerves, or the SO was painted with phenol to impair extrinsic nerves. Like controls, animals with a cut and reanastomosis at the proximal SO or at the SO-duodenal junction showed a normal fasting pattern of cyclic changes in SO spike-burst rate. In contrast, animals treated by a distal SO cut or phenol treatment at the distal SO lost the normal cyclic pattern of SO spike bursts and had a constant rate of approximately 4/min. A cut through the middle SO uncoupled the spike bursts in the proximal and distal SO. After feeding, all animals developed an SO spike-burst rate of 5-6/min that lasted for several hours. We conclude that the normal fasting pattern of SO spike bursts is regulated by extrinsic nerves that ascend cephalad along the sphincter segment, whereas the sustained increase in SO spike-burst rate after feeding is at least in part hormonal.

Suloctidil-induced hepatotoxicity

Suloctidil is a new drug that is currently being evaluated in many clinical trials for use in dementia and thrombotic disorders. Hepatotoxicity has to date been reported exclusively in the European literature, and the few available histologic descriptions have been reported in the French language. We report a case of suloctidil-induced hepatotoxicity documented by serum liver biochemical tests and liver biopsy. Histologic features included focal necrosis of hepatocytes, mild hyperplasia of Kupffer cells, and other features suggestive of mild acute hepatitis.

Occult thyroid pathology in the young adult: an autopsy study of 138 patients without clinical thyroid disease

Thyroid glands from autopsies on 138 adults, ages 20 to 40 years, with no known clinical or laboratory evidence of thyroid disease, were serially sectioned at 2 mm intervals and microscopically examined for occult thyroid disease and anatomic variations. Occult papillary carcinoma was found in 3% of the glands, along with a single case of medullary carcinoma. The prevalence of occult thyroid carcinoma in this group of young adults is significantly less than that reported in the literature in people over forty (P less than .001). The glands demonstrated a number of other morphologic changes of importance to surgical pathologists. The thyroid capsule was incomplete in 62% of the glands. Thyroid follicles were found in the capsule in 14% of cases and thyroid follicles or nodules were outside the gland in perithyroid connective tissue in 88% of cases. Thyroid follicles were identified in 7% of cases in perithyroid strap muscles attached to the pyramidal lobe. A number of other, less common anatomic variations were also seen.

Occult carcinoma of the breast masquerading as primary adenocarcinoma of the small intestine. A case report

A fifty-year-old woman with abdominal pain, diarrhea, and weight loss ultimately required exploratory laparotomy. The entire small intestine was extensively infiltrated by poorly differentiated adenocarcinoma; mesenteric lymph nodes and surrounding omentum were involved, but no extragastrointestinal tumor was found. A presumptive diagnosis of unresectable primary carcinoma of the small bowel was made. Chemotherapy was initiated with 5-fluorouracil 300 mg/m2/day by continuous intravenous infusion. Nine months later a left breast mass with multiple ipsilateral axillary and supraclavicular lymph nodes developed; biopsy revealed a poorly differentiated adenocarcinoma morphologically identical to the tumor involving her small bowel. In spite of breast irradiation and systemic hormonal therapy, the patient deteriorated rapidly and died from progressive metastatic disease.

Esthesioneuroblastoma masquerading as extramedullary plasmacytoma

Nine years after biopsy and radiation therapy for an extramedullary plasmacytoma of the nasal cavity, a 64-year-old man developed locally recurrent tumor. Repeat biopsy revealed tumor identical in hematoxylin and eosin stain (H & E) appearance to that found originally, leading to the diagnosis of recurrent extramedullary plasmacytoma. Neither the original tumor or its recurrence demonstrated features characteristic of esthesioneuroblastoma (e.g., nests, rosettes, ganglion cells, or fibrillary background). However, Gremilus staining and neuron specific enolase tests (immunoperoxidase method), done strictly as a teaching exercise, were strongly positive and eventually resulted in an altered diagnosis to esthesioneuroblastoma. This case underscores the difficulty that may be encountered in distinguishing these two pathologic entities of the nasal cavity solely on the basis of H & E staining. In view of differences in staging, evaluation, prognosis, and management, accurate differentiation of these two relatively uncommon tumors of the nasal cavity is of immediate clinical importance. These observations suggest that care should be taken to exclude the possibility of esthesioneuroblastoma before making the histologic diagnosis of extramedullary plasmacytoma of the nasal cavity.

Effects of auranofin and myochrysine on intestinal transport and morphology in the rat

Auranofin (SKF-D 39162) is an oral gold preparation for the treatment of rheumatoid arthritis. One of its major side effects is diarrhoea. To determine one possible mechanism for this we compared the effects of auranofin and myochrysine on intestinal water and solute transport in the rat. Jejunal perfusion with 2 mM auranofin (n = 5) induced fluid and electrolyte secretion and inhibited glucose absorption (p less than 0.01). Auranofin (0.2 mM) induced fluid secretion in the jejunum (n = 5; p less than 0.01) and colon (n = 6; p less than 0.01). In contrast, 2 mM myochrysine enhanced jejunal water and electrolyte absorption (n = 6; p less than 0.02). Both compounds enhanced absorption of mannitol (p less than 0.01). Perfusion of 0.2 mM auranofin for two hours had no significant effect on mucosal c-AMP levels (n = 4). After perfusion for two hours with 2 mM auranofin the jejunal mucosa showed severe injury by light and scanning electronmicroscopy while myochrysine had no apparent effect. The damage after perfusion with 0.2 mM auranofin for two hours was less severe. Auranofin was more rapidly absorbed than myochrysine (p less than 0.05). These effects provide an explanation for the diarrhoea associated with auranofin therapy.

Cutaneous complications in renal transplant recipients

Systematic review of the histologic characteristics of skin lesions biopsied and/or resected in a group of 580 renal transplant recipients collected over a 16-year period showed a total of 170 specimens from 120 patients. In this group there were 41 benign tumors, 22 infections, 35 inflammatory dermatoses, and 13 miscellaneous lesions. Fifty-nine lesions were malignant, and half of these were squamous cell carcinomas (SCCs). None were lethal or metastasized, although deeply invasive local recurrences and multiple lesions were common. Comparison with SCCs from a control group showed no clearcut differences with respect to level of invasion, grade, pattern, or presence of actinic change. Most of these lesions were found in sun-exposed areas, were associated with actinic changes, and with actinic keratoses. Problems in differentiating SCC from keratoacanthoma and the clinical implications of these difficulties are discussed in conjunction with a review of the literature.

Antigenic variation among Borrelia spp. in relapsing fever

Seven antigens of Borrelia hermsii, B. parkeri, and B. turicatae with isoelectric points in the range of 4.4 to 5.0 and molecular masses of 40 to 43 kilodaltons played a role in the relapse phenomenon of relapsing fever. Based upon location of the antigens in the outer envelope, the molecular weight, and Western blot analysis, the antigens from each phase of spirochetemia appeared to be a mixture of the serotype-specific antigens of cloned B. hermsii.

Comparison of cerebrospinal fluid C-reactive protein and lactate for diagnosis of meningitis

Levels of C-reactive protein and lactate were determined on 562 consecutive cerebrospinal fluid (CSF) samples from adult patients with a wide variety of central nervous system diseases to compare the sensitivity and specificity of CSF lactate and C-reactive protein for the rapid diagnosis of bacterial meningitis. Neither test alone, together, or in combination with elevated CSF leukocyte count and protein had a predictive value over 60% for a positive test in this group of patients with diverse central nervous system problems. Neither test is useful as a screening test for bacterial or mycotic meningitis. Also, in patients with partially treated bacterial meningitis, the tests are often negative. CSF lactate may be useful in differentiating aseptic from septic meningitis in selected patients.

Total or near total thyroidectomy versus limited resection for radiation-associated thyroid nodules: a twelve-year follow-up of patients in a thyroid screening program

Controversy continues regarding the extent of thyroidectomy appropriate for patients with radiation-associated thyroid nodules. The incidence of cancer in this group of patients is more than 50% when near total or total thyroidectomy is done and all thyroid tissue is serially sectioned and examined. Tumor multicentricity is common. Is total or near total thyroidectomy warranted in all of these patients? A prospective study and follow-up program of 2118 patients with prior low-dose head and neck irradiation who entered into a thyroid screening program allowed us to examine how the extent of thyroidectomy influenced the clinical course of these patients. Near total or total thyroidectomy was performed in 59 patients (36 had cancer), and limited thyroid resection, that is, lobectomy or less, was done in 78 patients (four of whom had cancer). During follow-up, only three patients have developed recurrent cancer; two had near total thyroidectomy and one had total thyroidectomy at first operation. Two patients with limited thyroid resection have had reoperation for new thyroid nodules, both of whom had benign nodules. We conclude that although limited thyroid resection may leave occult malignancies in unresected thyroid tissue, there is no significant difference in outcome between patients with limited resection and those with near total or total thyroidectomy after a 12-year follow-up of the program. Significant differences in cancer recurrence rats may occur with longer follow-up.