The Chernobyl thyroid cancer experience: pathology.

The Chernobyl accident was followed by a large increase in the incidence of thyroid carcinoma in the areas exposed to high levels of fallout. The Chernobyl Tumor Bank was set up in 1998 to make tumours available for study internationally, and a pathology panel reviewed all the tumours and established an agreed diagnosis. The thyroid tumours that were discovered after the Chernobyl nuclear accident were virtually all (95%) of the papillary carcinoma type. Rare examples of other tumour types were identified. Within the papillary group, several subtypes were noted, including classical or usual type, follicular variant, solid variant and mixed patterns Diffuse sclerosis variant, cribriform/morular type and Warthin-like variant were rare. No tall cell or columnar cell variants were identified. The tumours examined by the Pathology Panel of the Chernobyl Tumor Bank constitute a large representative sample (estimated at about 50%) of the tumours that developed in this population. This overview describes the method adopted by the panel and the different diagnostic categories adopted; illustrates the pathology of these neoplasms; compares the pathological characteristics of the early lesions with those identified after long latency periods and the institution of screening programmes and outlines the possible associated causes for the various morphological patterns seen.

Pitfalls in thyroid tumour pathology.

This review provides an itemized listing of major diagnostic pitfalls in the field of thyroid tumour pathology, emphasizing the features that the authors have found most useful in their recognition and avoidance.

Human mammaglobin mRNA is a reliable molecular marker for detecting occult breast cancer cells in peripheral blood.

Occult carcinoma cells in peripheral blood of breast cancer (BC) patients is generally associated with poor disease prognosis. Reverse transcriptase-polymerase chain reaction (RT-PCR) is a sensitive method for revealing rare circulating cancer cells. The target mRNA must be carefully chosen, as it must be expressed only by malignant cells. In this study, we developed a nested RT-PCR assay for mammaglobin (hMAM) and assessed both its specificity and its sensitivity in the detection of cancer cells in peripheral blood of BC patients. hMAM mRNA was detected by RT-PCR in 156/165 (95%) of fresh BC tissues analyzed. All samples from 66 healthy blood donors and 151 patients with benign breast disease were hMAM negative as assessed by nested RT-PCR. In contrast, hMAM was detected in 16/137 (12%) of peripheral blood samples deriving from BC patients: 0/9 in stage 0, 1/50 (2%) in stage I, 3/33 (9%) in stage II, 1/18 (5%) in stage III and 11/27 (41%) in stage IV. Using nested RT-PCR, we were able to amplify hMAM transcript of one tumour cell/10(6) normal cells. Our data demonstrate that hMAM mRNA detection by RT-PCR is a specific assay potentially suitable for identification of occult cancer cells in peripheral blood of BC patients.

Is the new WHO classification of neuroendocrine tumours useful for selecting an appropriate treatment?

BACKGROUND: Neuroendocrine tumours (NETs) are a rare and heterogeneous group of neoplasms. The most recent WHO classification provides clinical tools and indications to make the diagnosis and to suggest the correct treatment in different subgroups of patients. The aim of this trial was to apply the new classification criteria in clinical practice and, accordingly, to choose the most appropriate treatment. PATIENTS AND METHODS: Thirty-one evaluable patients, not previously treated, classified as advanced well differentiated NETs according to the new classification, were given long-acting release octreotide 30 mg every 28 days until evidence of disease progression. The treatment activity was evaluated according to objective, biochemical and symptomatic responses. Safety and tolerability were also assessed. RESULTS: Two partial objective tumour responses were obtained (6%), stabilization occurred in 16 patients (52%) and 95% of patients had a disease stabilisation lasting > or =6 months. However, eight patients showed rapid disease progression within 6 months of therapy and six patients after 6 months. Biochemical responses, evaluated by changes in serum chromogranine A levels were reported in 20/24 patients (83%). Symptomatic responses were observed in 6/14 patients (43%): a complete syndrome remission in one patient, partial syndrome remission in five patients, no change in four patients and progressive disease in four patients. The median overall survival was not reached, and the median time to disease progression was 18 months (range 1-49 months). The treatment was well tolerated, no severe adverse events were observed and no patient withdrew from the study because of adverse events. CONCLUSIONS: The WHO classification enables identification of low-grade NET patients who may be suitable for hormonal treatment. Octreotide LAR was seen to be effective in controlling the disease and was well tolerated. However, eight patients failed to respond to the treatment, despite histological evidence of a well differentiated tumour according to the new classification. This suggests that further histological examination should be carried out, especially in patients with visceral metastases and a short disease-free interval.

So-called inflammatory myofibroblastic tumour: a proliferative lesion of fibroblastic reticulum cells?

The term inflammatory pseudotumour was originally used in a generic fashion for any lesion which simulated a neoplastic condition at a clinical, macroscopic and microscopic level but which was thought to have an inflammatory/reactive pathogenesis. In more recent times, the term has been employed in a more restrictive sense for a mass lesion characterized microscopically by the proliferation of a spindle cell component against a heavy inflammatory infiltrate of mixed composition but usually with a predominance of mature lymphocyte and plasma cells. The spindle cell component has generally been regarded as being of mesenchymal nature and having morphological and phenotypical features consistent with fibroblasts or myofibroblasts, the latter cell being clearly preferred over the former in the more resent reports. The term inflammatory myofibroblastic tumour (IMFT) is the one currently favoured, which proposes the myofibroblastic nature of the process. It is the purpose of this review to bring forth some evidence that the neoplastic spindle cell component of IMFT may be instead derived from the subtype of cells of the accessory immune system that have been variously called fibroblastic reticulum cells, myoid cells, and dictyocytes.

DNA and RNA obtained from Bouin's fixed tissues.

BACKGROUND: The use in many countries of acid fixatives, such as Bouin's solution, has limited the use of archival tissue for molecular analysis. An acidic environment is one of the main causes of DNA degradation. Moreover, RNA extraction is difficult in these types of fixed tissues. AIMS: To amplify DNA and RNA from Bouin's fixed tissues. METHODS: DNA and RNA were extracted from 20 breast cancer samples that had been routinely fixed in Bouin's fixative. Amplification of several genes using primers that produced amplicons of different lengths was carried out using the polymerase chain reaction (PCR) for DNA (with and without restoration) and reverse transcription PCR for RNA. RESULTS: The acid environment of Bouin's fixative damaged both DNA and RNA. However, amplification was successful when the amplicon length was reduced to about 80 bp for RNA and 100-200 bp for DNA, especially if submitted to DNA reconstruction procedures. CONCLUSIONS: It is possible to recover and analyse DNA and RNA from Bouin's fixed and paraffin wax embedded tissues.

Status of surgical margins and prognosis in adult soft tissue sarcomas of the extremities: a series of patients treated at a single institution.

PURPOSE: To explore the prognostic effect of microscopic marginal status after surgery for extremity soft tissue sarcomas. PATIENTS AND METHODS: We analyzed 911 consecutive patients surgically treated throughout a 20-year span at a single referral center. Six hundred forty-two were first seen with a primary tumor, and 269, with a locally recurrent tumor. All patients underwent macroscopically complete resection. Microscopic marginal status was negative (tumor size > 1 mm) in 748 patients and positive (

Thyroid carcinoma after Chernobyl latent period, morphology and aggressiveness.

The large numbers of papillary thyroid carcinomas that have occurred in those exposed to high levels of short-lived isotopes in fallout after Chernobyl provide a unique opportunity to correlate latency and tumour biology. We show that short latency is associated with tumours with a phenotype that is significantly less structurally differentiated, shows significantly less peritumour fibrosis, and significantly more invasive spread when compared to tumours with a longer latent period. In contrast, the type of differentiation (papillary or follicular architecture) is associated with age at exposure. These findings suggest that the initial mutation at the time of exposure played a major role in tumour latency and aggressiveness. We and others have shown that RET-PTC3 rearrangements are associated with the solid morphology seen in these short latency tumours, while classical papillary carcinomas more often show RET-PTC1 rearrangements. Studies in transgenic mice show similar findings, and in vitro studies show that RET-PTC3 induces more rapid growth than RET-PTC1. We therefore suggest that the solid morphology, high frequency of RET-PTC3 rearrangements and aggressive behaviour noted in early investigations of post-Chernobyl tumours were characteristic of short latency rather than the nature of the mutagen, and that successive overlapping waves of papillary carcinoma with differing latency, differing patterns of mutations and differing clinical behaviour are occurring in those exposed to Chernobyl fallout.

Breast tumor resembling the tall cell variant of papillary thyroid carcinoma: report of 5 cases.

Five cases of a hitherto undescribed breast tumor having histologic features similar to those of the tall cell variant papillary thyroid carcinoma are described. They were composed of columnar mitochondrion-rich to oxyphilic cells arranged in nests, papillae, and follicle-like structures. In addition, the neoplastic cells showed numerous nuclear grooves and, in two cases, nuclear pseudo-inclusions. None of the patients had previous concomitant or subsequent evidence of a thyroid tumor. Immunohistochemistry further excluded a metastasis from the thyroid in the four cases tested, as they were consistently thyroglobulin and thyroid transcription factor 1 negative.

Quality of surgery and outcome in extra-abdominal aggressive fibromatosis: a series of patients surgically treated at a single institution.

PURPOSE: To explore prognostic factors in surgically treated aggressive fibromatosis (extra-abdominal desmoid tumor). PATIENTS AND METHODS: A total of 203 consecutive patients treated with surgery over a 35-year period at a single referral center were retrospectively reviewed. One hundred twenty-eight were first seen at our institution with primary disease, whereas 75 had a recurrent tumor. All patients underwent macroscopically complete resection. Margins were rated as negative in 146 (97 with primary tumors, 49 with recurrences) and positive in 57 (31 in primary, 26 in recurrences) patients. Median follow-up was 135 months. RESULTS: Patients with primary disease had a better disease-free survival rate than those with recurrence (76% v 59% at 10 years). Presenting with a recurrence was also the strongest predictor of local failure in the multivariate analysis. In patients first treated for primary disease, size and site had prognostic significance, whereas microscopically positive surgical margins did not. In contrast, in patients with recurrence, there was a trend toward better prognosis if margins were negative (although this was not significant at multivariate analysis). CONCLUSION: Presence of microscopic disease does not necessarily affect long-term disease-free survival in patients with primary presentation of extra-abdominal desmoid tumors. Thus, function-sparing surgery may be a reasonable choice when feasible without leaving macroscopic residual disease. In patients with recurrences, positive margins may more clearly affect prognosis, potentially necessitating adjuvant radiation in selected cases.

Primary monotypic epithelioid angiomyolipoma of bone.

AIMS: Monotypic epithelioid angiomyolipoma is a distinct and definable variant of angiomyolipoma, composed of monomorphous epithelioid cells that show HMB45 immunoreactivity. Angiomyolipoma, including its morphological variants, belongs to the family of perivascular epithelioid cell tumour. METHODS AND RESULTS: The tumour was examined using immunohistochemical staining and by transmission electron microscopy. Neoplastic cells showed a cytoplasmic granular positivity for HMB45. CONCLUSIONS: Extrarenal angiomyolipomas are rare and, to the best of our knowledge, this is the first reported case of a primary monotypic epithelioid angiomyolipoma of bone in a patient without evidence of tuberous sclerosis.

Cytokeratin 19 immunoreactivity in the diagnosis of papillary thyroid carcinoma: a note of caution.

To evaluate the expression of cytokeratin (CK) 19, we stained sections obtained from formalin-fixed, paraffin tissue blocks of 35 thyroid tumors (follicular adenoma [FA], 20; papillary thyroid carcinoma [PTC], 10 follicular variant [FV] and 5 usual type) and scored the extent of staining as follows: 1+ (<5% positively stained cells), 2+ (5%-25% positively stained cells), 3+ (25%-75% positively stained cells), and 4+ (>75% positively stained cells). All 15 PTCs (including 10 FV-PTCs) were CK19 positive: 14 were 4+ and 1 (FV-PTC) was 2+. All 20 FAs also were CK19 positive: 15 were 1+, 1 was 2+, 4 were 3+, and none was 4+. In the FAs that were scored 1+, reactivity usually was confined to follicular cells lining cystically dilated atrophic follicles that lacked the typical nuclear features of PTC. The remaining FAs showed more diffuse reactivity, which was, however, less intense than that observed in the PTCs. Thus, immunoreactivity for CK19 is not specific for PTC, although we acknowledge that the extent and intensity of staining are considerably greater in this tumor than in FA. There were no significant differences in staining for CK19 between nonneoplastic follicles adjacent to PTCs and those adjacent to FAs.

Merkel cell carcinoma of the parotid gland associated with Warthin tumour: report of two cases.

AIMS: Two cases of Merkel cell carcinoma occurring simultaneously and in close association with a Warthin tumour of the parotid gland are reported. METHODS AND RESULTS: The patients were a 65-year-old man and a 70-year-old man, respectively. The Merkel cell carcinoma component was immunoreactive for chromogranin and keratin 20 and contained neuroendocrine-type granules at the ultrastructural level. CONCLUSIONS: The histogenesis of this heretofore undescribed combination is discussed.

Solitary fibrous tumor of the thyroid gland: report of seven cases.

Solitary fibrous tumor is a soft tissue neoplasm initially described in the pleura but subsequently reported in a wide variety of locations. The clinical behavior is usually benign, but the existence of aggressive cases has been documented both in the pleura and in extrapleural sites. In this report clinical and pathologic features of seven solitary fibrous tumors of the thyroid gland are presented. Patients' ages ranged from 43 to 64 years (mean 52 years), and tumor sizes varied from 2 to 6 cm. Grossly, the tumors were white-tan and well circumscribed. Microscopically, there was a variegated, wavy, storiform, hemangiopericytic or desmoid-like arrangement of spindle cells. Trapped thyroid follicles within the tumor and peripheral jagged tumor infiltration among follicles were common. There was immunohistochemical reactivity for CD34, CD99, and bcl-2, and ultrastructural analysis of one tumor was consistent with a fibroblastic lineage. The differential diagnosis included other benign and malignant mesenchymal tumors of the thyroid, spindle cell follicular adenoma, Riedel's thyroiditis, the spindle cell, and paucicellular variants of anaplastic carcinoma, papillary thyroid carcinoma with exuberant nodular fasciitis-like stroma, and the spindle epithelial tumor with thymus-like differentiation. The cumulative data of 13 cases (comprised of the seven present cases and the six previously reported) suggest a benign clinical behavior for thyroid SFT.

Expression of thyroid transcription factor-1 and other markers in sclerosing hemangioma of the lung.

CONTEXT: Sclerosing hemangioma of the lung is well characterized histologically, but the line of differentiation expressed by the tumor cells has been unclear. Despite the implication by its name of a vascular neoplasm, sclerosing hemangioma is considered by most authorities to be an epithelial tumor, possibly related to the pulmonary epithelium. OBJECTIVES: To determine the line of differentiation of the tumor cells with immunohistochemistry and to review the related literature. DESIGN: Nine cases of histologically typical pulmonary sclerosing hemangioma were studied with pan-epithelial (epithelial membrane antigen [EMA] and CAM 5.2), endothelial (CD31), neuroendocrine (chromogranin A), and pulmonary epithelial markers (thyroid transcription factor-1 and PE10). Staining intensity was separately evaluated in the pale cells of the solid areas and the cells lining the papillary structures. RESULTS: Both cell types were positive for thyroid transcription factor-1 and EMA in all cases (100%). Thyroid transcription factor-1 showed diffuse strong staining, and EMA staining varied from focal weak to diffuse strong. The pale cells showed focal staining for keratin (CAM 5.2) in 2 (28%) of 7 cases, and for PE10 in 5 (62%) of 8 cases. The papillary lining cells were at least focally positive with CAM 5.2 and PE10 in all cases (100%). Reactions for chromogranin and CD31 were negative in both cell types in every case. The number of PE10- or CAM 5.2-positive papillary lining cells was less than the number of EMA-positive papillary lining cells. CONCLUSION: The uniform positivity for EMA is consistent with the notion that the tumor cells of sclerosing hemangioma are epithelial, and the strong thyroid transcription factor-1 positivity suggests differentiation toward pulmonary epithelium. The papillary lining cells expressing EMA as well as PE10 or CAM 5.2 likely represent entrapped metaplastic alveolar epithelium, whereas the papillary lining cells expressing only EMA more likely constitute true neoplastic cells similar to those in the solid areas.

Association of lymphangioleiomyomatosis (LAM) with endosalpingiosis in the retroperitoneal lymph nodes: report of two cases.

We report 2 patients in whom pulmonary lymphangioleiomyomatosis (LAM) affected the retroperitoneal lymph nodes and was associated with endosalpingiosis. These lesions were large, encapsulated masses with multiple cysts containing chylous fluid. Both were characterized by proliferating LAM cells that formed fascicles separated by slit-like channels. Some cysts were lined by ciliated epithelium resembling that of Fallopian tubes. Other cysts were lined either by flattened endothelial cells or by a mixture of these cells and epithelial cells. Many LAM cells gave a positive reaction with HMB-45 antibody. Most LAM cells in fascicles were reactive for alpha-smooth muscle actin and desmin. In 1 patient, many of the epithelial cells and some of the subjacent LAM cells were positive for estrogen and progesterone receptors. In conclusion, immunostaining with HMB-45 antibody and markers for smooth muscle cells can be helpful in the evaluation of problems in the differential diagnosis of lesions of extrapulmonary LAM, particularly those involving the genital system.