Chromogranin a Measurement in Neuroendocrine Tumors

Neuroendocrine tumors (NETs) are rare neoplasms characterized by a low proliferative index and, in some cases, a favorable prognosis. These tumors often overproduce and release biologically active substances that are responsible for severe syndromes. Tumor marker measurement provides the clinician with useful information for the management of NET patients. The substances released by overproducing tumors are currently used as biomarkers, but there is a need for sensitive markers also for the “biochemically silent” NETs. The most effective and reliable blood marker available today is chromogranin A (CgA). Because of its high sensitivity and specificity, this glycoprotein can be used for the diagnosis, prognosis and follow-up of NETs. Furthermore, CgA measurement can be used for monitoring those tumors not overproducing or releasing any hormones or biological amines. This paper is a synthetic review on the value of CgA in NET management and reports our experiences with CgA measurement in NET patients.

Hormone receptor status and survival of medullary breast cancer patients. A Turkish cohort

Objectives:

To analyze the relationship between clinical features, hormonal receptor status, and survival in patients who were diagnosed with medullary breast cancer (MBC).

Methods:

Demographic characteristics, histopathological features, and survival statuses of 201 patients diagnosed with MBC between 1995 and 2015 were retrospectively recorded. Survival analyses were conducted with uni- and multivariate cox regression analysis.

Results:

Median follow-up time was 54 (4-272) months. Median patient age at the time of diagnosis was 47 years old (26-90). Of the patients, 91.5% were triple negative. Five-year recurrence free survival time (RFS) rate was 87.4% and overalll survival (OS) rate 95.7%. For RFS, progesterone receptor (PR) negativity, atypical histopathological evaluation, absence of lymphovascular invasion, smaller tumor, lower nodal involvement were found to be favourable prognostic factors by univariate analysis (p<0.05). The PR negativity and smaller tumor were found to be favourable factors by univariate analysis (p<0.05). However, none of these factors were determined as significant independent prognostic factors for OS (p>0.05).

Conclusion:

Turkish MBC patients exhibited good prognosis, which was comparable with survival outcomes achieved in the literature. The PR negativity was related to a better RFS and OS rates.

Topoisomerase II alpha and microtubule-associated protein-tau as a predictive marker in axillary lymph node positive breast cancer

AIMS AND BACKGROUND

The aims of this study were to investigate the correlation between topoisomerase II alpha (TOP2A), microtubule-associated protein-tau (MAP-tau) and other prognostic factors in breast cancer and to evaluate the predictive value of TOP2A and MAP-tau in breast cancer patients who received anthracycline and taxane-containing adjuvant chemotherapy.

METHODS AND STUDY DESIGN

Seventy patients with axillary lymph node positive breast cancer who underwent curative surgery between January 2000 and December 2005 were evaluated retrospectively. The levels of protein expression of TOP2A and MAP-tau were assessed using immunohistochemistry.

RESULTS

Among the 70 patients, 43 (61.4%) showed TOP2A overexpression and 30 (42.9%) showed MAP-tau positivity. TOP2A overexpression was associated with p53 positivity and high histological grade. MAP-tau positivity was associated with a lower positive lymph node ratio, lower proliferative activity, and hormone receptor positivity. Based on the TOP2A and MAP-tau expression, there was no significant difference in disease-free survival in the breast cancer patients who received anthracycline and taxane-containing adjuvant chemotherapy.

CONCLUSIONS

We conclude that immunohistochemical analysis of TOP2A and MAP-tau protein expression may not predict the benefits of adjuvant anthracycline and taxane chemotherapy in axillary node positive breast cancer.

Poorly differentiated medullary carcinoma of the colon with an unusual phenotypic profile mimicking high grade large cell lymphoma - a unique case report and review of the literature

Medullary carcinoma (MC) of the colon and rectum is a rare entity, accounting for less than 0.1% of colonic adenocarcinoma that poses a diagnostic challenge for the practicing pathologist. Poorly differentiated or undifferentiated MC with an unusual histological appearance and immunoprofile in addition to heavy lymphoid infiltrate could make it problematic when differentiating it from a high grade lymphoma, in particular anaplastic large B- or T-cell lymphoma, plasmablastic lymphoma, and other undifferentiated neoplasms. Here we reported a unique case of an 81 y/o woman presenting with a 7.0 cm colon mass detected by computed tomography (CT) scan. A partial transverse and ileum resection with appendectomy were performed. Microscopic examination revealed sheets of large, pleomorphic, mitotically-active cells with abundant eosinophilic cytoplasm and multiple prominent nucleoli, growing with a pushing border and poor glandular formation in a background of intratumoral lymphocytes. The neoplastic cells were only focally positive for keratins (<10%); diffusely and strongly positive for vimentin and CD10 with high proliferative index (Ki-67, 90%). The tumor cells were also aberrantly positive for CD30, CD79a and CD43 (diffusely or focally), resulting in a diagnostic dilemma between colonic MC and high grade lymphoma. Careful examination and additional immunohistochemical stains performed proved there was no evidence of T or B-cell lymphoma, melanoma, or other types of primary colon or metastatic carcinomas. This case highlights the difficulty in distinguishing a high grade lymphoma and poorly differentiated colonic MC, and, also the aberrant expression of CD10 and a significant loss of pancytokeratin could result in a diagnostic pitfall.

[Medullary carcinoma experience in breast oncology unit of Hospital Juarez Mexico]

BACKGROUND

Medullary breast cancer is a rare type, considered of good prognosis.

OBJECTIVE

To know the epidemiological and clinical characteristics of the population attended in the Hospital Juarez de Mexico, to know if they are alike to described worldwide and if the treatments proposed internationally are applicable for this hospitable center.

METHODS

We performed a retrospective analysis. Reviewing the records with histopathologic diagnosis of medullary breast cancer from February 1993 to February 2011. Finding 41 patients in the oncology unit of the institution.

RESULTS

We report an incidence of 3.04%, originating in 11 Mexican States, with a low to middle socioeconomic level in 39.02%. The average age at the time of diagnosis was 50 years. No family history was reported but some patients had medical history for type 2 diabetes, hypertension and previous breast cancer. 63.41% were menopausal. The average clinical size of the tumor was 58 mm. The 63% of the cases were located in the left breast. The 53.1% were clinical stages I and II, 46.3% were clinical stages III and in 9.6% of the cases primary tumor could not be assessed. Only 47% of the patients had positive axillary lynph nodes at diagnosis. The inmunohistochemestry was only reported in 14 of the 41 patients, according to the molecular classification of breast cancer: 8 were triple negative, 2 luminal A, 1 luminal B and 3 Her2neu.

CONCLUSIONS

The Mexican population presents epidemiological and clinical characteristics similar to those patients described in other studies worldwide.

An associated classification of triple negative breast cancer: the risk of relapse and the response to chemotherapy

BACKGROUND

Triple negative breast cancer (TNBC) is heterogeneous and considered as an aggressive tumor. This study was to evaluate the associated classification and its correlations with prognosis and the response to chemotherapy in Chinese women.

METHODS

Four hundred and twenty-eight cases of invasive TNBC were involved in this study. The expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), and cytokeratin 5/6 (CK5/6), Ki67 and p53 were analyzed by immunohistochemistry and compared with patient outcome, and its implications and chemotherapy response were evaluated in four subgroups: typical medullary carcinoma (TMC), atypical medullary carcinoma (AMC), non-specific invasive ductal carcinoma (IDC) and other types.

RESULTS

The factors of tumor grade, tumor stage, lymph node status, EGFR/CK5/6 status and p53 labeling index were different among the groups. TMC tumors had the lowest rate of relapse (5.8%), while AMC, IDC and other types were associated with an increased risk of relapse (19.1%, 26.7% and 38.2% respectively). Many factors were risk predictors of relapse for TNBC and IDC, while only positive lymph node was for AMC. For MC tumors, adjunctive chemotherapy decreased the risk of relapse in lymph node positive subgroup (36.8% and 66.7%), while not significant in lymph node negative one (8.1% and 10.0%).

CONCLUSION

The classification based on histologic and IHC findings may be a significant improvement in predicting outcome in TNBC. The different chemotherapy response in subgroups may contribute to guiding the treatment of TNBC.

Medullary carcinoma of the breast: ten year clinical experience of the Kuwait cancer control centre

BACKGROUND

Medullary carcinomas of the breast account for fewer than 7% of all invasive breast cancers. Some investigators include medullary carcinomas in the favourable histologic subtype, despite its aggressive histologic appearance. However, others fail to confirm its favourable prognosis.

METHODS

This was a retrospective analysis of sixty-one (61) cases of breast cancer cases diagnosed with Medullary Carcinoma, presenting to the Kuwait Cancer Control Center between 1995 and 2005.

RESULTS

Median survival time was 122 months and the seven-year disease free survival was 82%. Overall survival rate was not assessed as no cases died during the study period. No cases were metastatic from the start and only eight cases developed metastases, local recurrence or contralateral breast primary. 68.8% of the cases were Stage I or IIA (i.e. no lymph node affection).

CONCLUSION

There is no overt favourable prognosis of medullary carcinoma when compared to invasive ductal carcinoma. Prognosis is more related to stage than histologic subtyping. The majority of cases were negative estrogen and progesterone receptor status and node negative.

Localization of medullary thyroid carcinoma after surgery using (11)C-methionine PET/CT: comparison with (18)F-FDG PET/CT

Tumor localization is difficult in patients with medullary thyroid carcinoma (MTC) that have persistent hypercalcitoninemia after thyroidectomy. In this study, the (11)C-methionine positron emission tomography/computed tomography (PET/CT) was compared with the (18)F-FDG PET/CT for diagnostic sensitivity in detecting residual or metastatic disease. (11)C-methionine PET/CT and (18)F-FDG PET/CT were performed on 16 consecutive patients with MTC that had persistent hypercalcitoninemia after surgery in this prospective, single-center study. Patient- and lesion-based analyses were performed using a composite reference standard which was the sum of the lesions confirmed by all combined modalities, including neck ultrasonography (US) with or without fine needle aspiration cytology, CT, bone scan, magnetic resonance imaging (MRI), and surgery. By patient-based analysis, the sensitivities of (11)C-methionine PET/CT and (18)F-FDG PET/CT were both 63%. By lesion-based analysis, the sensitivity of (11)C-methionine PET/CT was similar to (18)F-FDG PET/CT (73% vs. 80%). Excluding hepatic lesions, which could not be detected because of physiological uptake of methionine by the liver, the sensitivity of (11)C-methionine PET/CT was better than (18)F-FDG PET/CT especially for detecting cervical lymph node lesions; however, it was not superior to US. All patients with serum calcitonin levels ≥370 pg/mL showed uptake by (11)C-methionine PET/CT and (18)F-FDG PET/CT. This preliminary data showed that despite its similar sensitivity to (18)F-FDG PET/CT for detecting residual or metastatic MTC, (11)C-methionine PET/CT provided minimal additional information compared to combined (18)F-FDG PET/CT and neck US.

Tenascin C in medullary thyroid microcarcinoma and C-cell hyperplasia

Tenascin C (Tn-C) is an extracellular matrix glycoprotein that is expressed early in carcinogenesis including intraepithelial neoplastic lesions of different organs. In this study, we analyze whether stroma reaction seen by Tn-C expression is detected early in tumorigenesis of medullary thyroid carcinoma (MTC) including medullary microcarcinoma and C-cell hyperplasia (CCH), which is accepted to be a precursor lesion of MTC in the setting of RET oncogene germ-line mutation. Tn-C was expressed in the stroma of all medullary microcarcinoma and in the stroma next to CCH. Stromal Tn-C expression was significantly more often seen in CCH with concomitant MTC than in isolated CCH of hereditary as well as nonhereditary cases (p = 0.001 and p = 0.016, respectively). We conclude that Tn-C expression and thus early stroma remodeling is seen in medullary microcarcinoma and CCH. Stromal Tn-C expression seems to be an indicator of a further step in carcinogenesis of MTC irrespective of a RET oncogene germ-line mutation.

PET imaging in neuroendocrine tumors: current status and future prospects

Neuroendocrine tumors (NET) are relatively rare diverse group of tumors that possess several unique characteristics and occur most commonly in the gastrointestinal tract. An important feature of these tumors is that they express somatostatin (SST) receptors, and thus can be successfully targeted with specific radiolabeled SST receptor related compounds. This has led to the introduction of multitude of single photon emission computed tomography (SPECT) and positron emission tomography (PET) tracers, which have significantly improved the ability for imaging these neoplastic lesions with high spatial resolution in the abdomen and elsewhere in the body. The introduction of Gallium-68 labeled radiopharmaceuticals as viable PET agents have added a new dimension to the management of patients with NET by providing high quality images compared with planar or SPECT with single photon emitting preparations. (18)F-labeled DOPA has demonstrated impressive results in differentiating between focal and diffuse disease in hyperinsulinism of the newborn which appears to be of crucial clinical benefit and has altered the management of these patients significantly. With regard to other types of NET, the current experience with such agents is relatively limited and therefore prospective studies are required to further define the role of PET in this complicated group of patients.

Renal medullary carcinoma: report of seven cases from Brazil

We report seven cases of renal medullary carcinoma collected from several institutions in Brazil. In spite of a relatively high incidence of sickle cell trait in Brazil, this is a rare tumor. All patients were males between the ages of 8 and 69 years (mean 22 years). From the collected information, the most frequent presenting symptoms were gross hematuria and flank or abdominal pain. The duration of symptoms ranged from 1 week to 5 months. Most of the tumors were poorly circumscribed arising centrally in the renal medulla. Size ranged from 4 to 12 cm (mean 7 cm) and hemorrhage and necrosis were common findings. All seven cases described showed sickled red blood cells in the tissue and six patients were confirmed to have sickle cell trait. All cases disclosed the characteristic reticular pattern consisting of tumor cell aggregates forming spaces of varied size, reminiscent of yolk sac testicular tumors of reticular type. Other findings included microcystic, tubular, trabecular, solid and adenoid-cystic patterns, rhabdoid-like cells and stromal desmoplasia. A peculiar feature was suppurative necrosis typically resembling microabscesses within epithelial aggregates. The medullary carcinoma of the 69-year-old patient was associated with a conventional clear cell carcinoma. To our knowledge, this association has not been previously reported and the patient is the oldest in the literature. The survival after diagnosis or admission ranged from 4 days to 9 months. The 8-year-old African-Brazilian patient with a circumscribed mass is alive and free of recurrence 8 years after diagnosis. This case raises the question whether a periodic search for renal medullary carcinoma in young patients who have known abnormalities of the hemoglobin gene and hematuria could result in an early diagnosis and a better survival.

Medullary thyroid carcinoma metastatic to the pituitary gland: an unusual site of metastasis

We present a case of metastatic medullary thyroid carcinoma involving the pituitary gland of a 23-year-old woman with multiple endocrine neoplasia type 2b who presented with diabetes insipidus and visual loss. The diagnostic features, including cytomorphology and immunohistochemistry, used to differentiate pituitary adenoma from metastatic medullary carcinoma are discussed. Pituitary metastases and tumor-to-tumor metastases in this region are also highlighted.

Molecular characterization of the desmoplastic tumor stroma in medullary thyroid carcinoma

Medullary thyroid carcinomas are aggressive neoplasias that metastasize very early to loco-regional lymph nodes, and tumors with a desmoplastic stromal reaction have a higher incidence of lymph node metastasis. In order to characterize the desmoplastic response in thyroid cancers, we evaluated the expression pattern of three molecular markers of activated fibroblasts/myofibroblasts, namely, fibroblast activation protein alpha (FAPalpha), tenascin-C (Tn-C), and alpha-smooth muscle actin (alpha-SMA), as well as the endothelial markers endoglyx-1, CD34 and CD31 in a series of 28 metastatic and non-metastatic medullary thyroid cancers. Immunohistochemical studies demonstrated that the three fibroblast activation markers (FAPalpha, Tn-C, alpha-SMA) are consistently expressed in the peritumoral and intratumoral stromal compartment of medullary thyroid carcinomas and expression of FAPalpha and Tn-C correlated with the degree of desmoplasia determined histologically (p=0.001 for FAPalpha and p<0.001 for Tn-C). Moreover, the extent of desmoplasia as well as the expression of FAPalpha and Tn-C correlated with the presence of lymph node (LN) metastases (p=0.002, p=0.005 and p=0.002, respectively). No correlation was found between the microvessel density (neoangiogenesis) in the tumor stroma, assessed with the endoglyx-1, CD34 and CD31 markers, and the degree of desmoplasia or incidence of LN metastases. Using a bioinformatics-based search of the BioExpresstrade mark database we found in a series of 48 thyroid cancers a significant correlation between FAPalpha RNA expression and incidence of LN metastases also in papillary cancers. These findings suggest that the link between specific molecular markers of tumor stromal reaction and locoregional metastasis extends from medullary to other thyroid cancer types.

Role of FNA cytology and immunochemistry in the diagnosis and management of medullary thyroid carcinoma: Report of six cases and review of the literature

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine thyroid malignancy. This study retrospectively reviewed 10 fine-needle aspiration samples from six MTC patients. Aspirated specimens were from thyroid (3), cervical lymph nodes (5), left lung (1), and anterior chest wall (1). Cytomorphology consisted predominantly of plasmacytoid cells (3 cases), spindle cells (2 cases), and epithelioid cells (1 case). However, all specimens had a mixture of other cell types and "salt and pepper" chromatin. Only one specimen showed Congo-red-positive amyloid. Calcitonin was expressed in 7/7 specimens. Four patients underwent surgical excision and MTC was confirmed in all four. Follow-up studies included serum calcitonin (3/6 cases) and imaging (2/6 cases). One patient had MTC associated with multiple endocrine neoplasia IIA syndrome and one had familial MTC with a history of MTC in mother. In conclusion, the cytomorphology of MTC is typical and calcitonin immunostain is a reliable method for confirming primary or metastatic MTC. Early cytological diagnosis of MTC positively impacted patient management. Follow-up with serum calcitonin and imaging is helpful in the early detection of recurrences.

Comparison of immunohistochemistry by automated cellular imaging system (ACIS) versus fluorescence in-situ hybridization in the evaluation of HER-2/neu expression in primary breast carcinoma

AIMS

Immunohistochemistry (IHC) and fluorescence in-situ hybridization (FISH) are both commonly used assays for evaluation of HER-2/neu status in breast cancer. However, there is still no consensus on which method is most predictive of patient response to Herceptin. Recently, the automated cellular imaging system (ACIS) has been shown to improve the accuracy and reproducibility in scoring IHC. Our aim was to compare the results of HER-2/neu expression and gene amplification in the same patients by IHC using the ACIS system and by FISH.

METHODS AND RESULTS

Two hundred and forty-seven breast cancer cases were studied. The concordance rate between IHC-ACIS (> or = 2.2) and FISH (> or = 2.0) was 94%. Fifteen patients were discordant; three had borderline FISH values and three had borderline IHC values. The other nine discordant cases consisted of five IHC-ACIS+, FISH- and six IHC-ACIS-, FISH+. HER-2/neu overexpression was more common in tumours that were high-grade, aneuploid, progesterone receptor and bcl-2 negative, with MIB-1 > 10%.

CONCLUSION

HER-2/neu assessment by the ACIS is reliable, rapid and inexpensive, and correlates highly with results obtained by FISH.

Mixed medullary and follicular cell carcinoma of the thyroid with lymph node metastasis in a 7-year-old child

A 7-year-old boy presented with midline swelling in the neck. On fine-needle aspiration cytology it was diagnosed as papillary carcinoma of the thyroid. The patient underwent total thyroidectomy. Histopathological examination, immunohistochemistry and electron microscopy revealed the presence of two intermingled components: medullary carcinoma and papillary carcinoma. One of the submandibular lymph nodes had metastasis of both the components. The case was diagnosed as 'mixed medullary and follicular cell carcinoma' with papillary carcinoma pattern and lymph node metastasis. Mixed medullary and follicular cell carcinoma with intermingling of medullary and papillary carcinoma components is a rare tumor. In adults, only eight such cases with lymph node metastasis have been published. To the best of the authors' knowledge no pediatric case has previously been reported in the English-language literature.

Somatostatin receptor imaging for neuroendocrine tumors

Tumors and metastases that express the somatostatin receptor subtypes sst2 sst3 or sst5 can be visualized in vivo after injection of radiolabeled octapeptide somatostatin analogs, like (111)In-pentetreotide. (111)In-pentetreotide scintigraphy also allows for more accurate staging of the disease by demonstrating tumor sites, which were not shown by conventional imaging. (111)In-pentetreotide scintigraphy may also detect resectable tumors that would have remained unrecognized using conventional radiological imaging techniques; it may prevent surgery with curative intent in those patients whose tumors have metastasized to a greater extend than could be detected with conventional radiological imaging and it may be used to select patients for treatment with the currently available octapeptide somatostatin analogs or with tumor targeted radioactive treatment with radiolabelled somatostatin analogs. (111)In-pentetreotide scintigraphy has also been used to select patients with pituitary tumors for medical treatment with octapeptide analogs, but its clinical usefulness for this purpose seems to be limited. It further allows scar tissue to be differentiated from tumor recurrence after the pituitary surgery or radiotherapy. However, a large variety of lesions in and around the pituitary region also express somatostatin receptors and, therefore, can be visualized by (111)In-pentetreotide scintigraphy.

Ghrelin in human medullary thyroid carcinomas

OBJECTIVE

Ghrelin is a novel gastrointestinal hormone involved in several metabolic functions. It has been identified previously in several normal and tumoral neuroendocrine tissues, including human medullary thyroid carcinomas (MTCs). The aim of the study was to evaluate ghrelin levels in patients with MTC and nontoxic goitre (NTG) with elevated calcitonin (CT) levels, as an additional marker of the disease.

PATIENTS AND DESIGN

The study included 22 patients with MTC (four before and 18 after thyroidectomy), 12 patients with NTG with basal CT levels exceeding 10 ng/l and 15 healthy subjects matched for age, sex and body mass index (BMI). After thyroidectomy, MTC patients were considered cured when basal and pentagastrin-stimulated CT levels were < 0.2 and < 10 ng/l, respectively. A pentagastrin-induced CT peak over 50 ng/l was considered as an abnormal response while 100 ng/l was the cut-off accepted for the diagnosis of C-cell hyperplasia or tumour. Circulating ghrelin and CT levels were evaluated at baseline in patients and controls and at -10, 0, 1, 2, 5 and 15 min after pentagastrin injection (0.5 microg/kg body weight) in 12 patients with MTC and nine with NTG. Four surgically removed MTCs were tested for ghrelin expression.

MEASUREMENTS

Total plasma ghrelin and CT levels were measured with a commercially available radioimmunoassay (RIA) and two-site chemiluminescence immunometric assays, respectively. In paraffin-embedded MTC samples ghrelin immunostaining was performed with a polyclonal antibody (1:1000) and the reaction visualized by an indirect immunoperoxidase system.

RESULTS

Plasma ghrelin levels found in cured or not cured MTC and in NTG patients were similar to those of BMI-matched healthy controls. No correlation between ghrelin and CT levels, thyroid disease or previous thyroidectomy was observed. The administration of pentagastrin caused a 17% increase in ghrelin levels (basal ghrelin vs. peak: 162 +/- 62 pmol/l vs. 189 +/- 58 pmol/l, P < 0.05) that was particularly evident (33% increase) in patients with an abnormal CT response to the test (CT > 50 ng/l). Immunohistochemistry showed positivity for ghrelin in a small proportion of CT positive cells from the four MTCs removed.

CONCLUSIONS

Patients with MTC, NTG and controls showed similar ghrelin levels, ruling out this parameter as a marker of MTC. The increase in ghrelin levels in patients with a positive CT response to pentagastrin, together with the immunopositivity for ghrelin in some MTC cells, suggests C cells as minor source of ghrelin production.

Novel Ganglioside Antigen Identified by B Cells in Human Medullary Breast Carcinomas: The Proof of Principle Concerning the Tumor-Infiltrating B Lymphocytes

The potential tumor-recognizing capacity of B cells infiltrating human breast carcinoma is an important aspect of breast cancer biology. As an experimental system, we used human medullary breast carcinoma because of its heavy B lymphocytic infiltration paralleled to a relatively better prognosis. Ig-rearranged V region V(H)-J(H), Vkappa-Jkappa, and Vlambda-Jlambda genes, amplified by RT-PCR of the infiltrating B cells, were cloned, sequenced, and subjected to a comparative DNA analysis. A combinatorial single-chain variable fragment Ab minilibrary was constructed out of randomly selected V(H) and Vkappa clones and tested for binding activity. Our data analysis revealed that some of the V(H)-J(H), Vkappa-Jkappa, and Vlambda-Jlambda region sequences were being assigned to clusters with oligoclonal predominance, while other characteristics of the Ab repertoire were defined also. A tumor-restricted binder clone could be selected out of the single-chain variable fragment kappa minilibrary tested against membrane fractions of primary breast tumor cells and tumor cell lines, the V(H) of which proved to be the overexpressed V(H)3-1 cluster. The specific binding was confirmed by FACS analysis with primary breast carcinoma cells and MDA-MB 231 cell line. ELISA and thin layer chromatography dot-blot experiments showed this target Ag to be a ganglioside D3 (GD3). Our results are a proof of principle about the capacity of B cells infiltrating breast carcinomas to reveal key cancer-related Ags, such as the GD3. GD3-specific Abs may influence tumor cell progression and could be used for further development of diagnostic and/or therapeutic purposes.

Sporadic medullary carcinoma of the colon: a clinicopathologic comparison with nonhereditary poorly differentiated enteric-type adenocarcinoma and neuroendocrine colorectal carcinoma

We studied 68 sporadic colorectal carcinomas (CRCs) with medullary features (MCRCs) and compared them with 35 poorly differentiated purely "enteric" CRCs (ECRCs) and 15 purely neuroendocrine carcinomas (NECs) of grades II and III, all in patients lacking a family history of CRC. Potential clinicopathologic differences between the study groups were assessed. MCRCs were significantly more common in the ascending colon than were ECRCs, but there was no significant dissimilarity to NECs. ECRCs occurred more often in the rectosigmoid than MCRCs or NECs. MCRCs arose in older patients, and a marked sex difference also was noted. Despite an infiltrative growth pattern, MCRC was less likely than ECRC to manifest with stage III or IV disease, but there was no stage-related difference from NECs. Although the histologic images of MCRCs were evocative of neuroendocrine differentiation, chromogranin positivity and synaptophysin reactivity in that group did not differ meaningfully from that of ECRCs but was dissimilar to the 100% labeling of NECs. p53 immunolabeling was similar in the 3 tumor groups. Follow-up data in the study cases showed that 5-year mortality was 40% (27/68) for MCRC, 59% (19/32) for ECRC, and 93% (14/15) for NEC. Medullary CRC seems to be a distinct clinicopathologic variant of CRC, which does not have a neuroendocrine lineage. The biologic behavior of MCRC was better than that of ECRC or NEC.

[Assay of thyrocalcitonin in cervical lymph node using fine-needle washings for the diagnosis of disseminated medullary thyroid carcinoma]

Fine-needle aspiration biopsy of cervical lymph nodes was carried out in 22 patients with suspected metastatic involvement with medullary thyroid carcinoma (MTS). It was followed by cytopathological examination of aspirates and assay of of thyrocalcitonin (TCT) in fine-needle washings. TCT determinations proved highly informative as well as significantly high in all seven cases of MTS involvement (26-8,484.87 pg/ml, mean 2,208 +/- 1,722 pg/ml).

Simultaneous occurrence of medullary and papillary carcinomas of the thyroid gland with metastases of papillary carcinoma to the cervical lymph nodes and the coinciding small B-cell lymphocytic lymphoma of the lymph nodes--a case report

We report a case of a simultaneous occurrence of medullary and papillary carcinomas of the thyroid gland with metastases of a papillary carcinoma to the cervical lymph nodes and a concurrent small B-cell lymphocytic lymphoma revealed in the lymph nodes examined in a 71-year-old woman. The diagnosis was based on microscopic examination of surgical specimens and supported by immunohistochemistry. Additionally, P53 and RET mutation analysis was performed. In this case, the coincidence of medullary and papillary carcinomas of the thyroid gland may account for a true composite tumor. The coexistence of a small B-cell lymphoma in our patient may be explained by irradiation treatment undergone during the adolescence.

Cushing's syndrome due to medullary thyroid carcinoma: diagnosis by proopiomelanocortin messenger ribonucleic acid in situ hybridization

Medullary thyroid carcinoma (MTC) rarely causes ectopic ACTH syndrome. We describe a 38-yr-old man with renal stones who had a 5-cm MTC removed in 1992. He was RET-protooncogene positive (codon 618). Serum calcitonin was 1597 pg/ml postoperatively. In 1996 he had rib fractures, bruising, weakness, and three to four stools per day. Laboratory studies revealed an elevated 24-h urine-free cortisol (780 micro g/d), epinephrine (66 micro g/d), and calcium (558 mg/d). Baseline serum cortisol was 23.9 micro g/dl and decreased to 12.9 and 4.5 micro g/dl after 2 mg and 8 mg dexamethasone suppression, respectively. Plasma ACTH was 170 pg/ml and decreased to 75 and 24 pg/ml after dexamethasone. Bone density t-score was -4.3 (trochanter). Computed tomography scans showed multiple cervical nodes and 2-cm right adrenal nodule. Magnetic resonance imaging (MRI) scan showed a prominent, homogeneous pituitary; the adrenal MRI scan was not typical for a pheochromocytoma. Serum CRH was less than 6.6 pg/ml. Bilateral adrenalectomy revealed two adjacent right adrenal pheochromocytomas and corrected the elevated urine cortisol (30 micro g/d), epinephrine (0 micro g/d), and calcium (281 mg/d) but not plasma ACTH (125 pg/ml). Neck dissection reduced calcitonin by 96% (5300 to 120 pg/ml) and ACTH by 91% (125 to 11 pg/ml). Carcinoembryonic antigen was reduced from 32.0 to 2.3 ng/ml. Immunohistochemical stain was negative for ACTH in the MTC-positive lymph nodes and the pheochromocytoma. Proopiomelanocortin mRNA by in situ hybridization was positive in the MTC but not in the pheochromocytoma. A repeat pituitary MRI scan was normal. The differential diagnosis of ACTH-dependent Cushing's syndrome in this case included pituitary disease or ectopic ACTH, either from medullary thyroid carcinoma or pheochromocytoma. ACTH stains were unrevealing, but proopiomelanocortin mRNA in situ hybridization in MTC tissue and plasma ACTH response to neck dissection confirmed MTC as the source of ectopic ACTH.

Focal adhesions and associated proteins in medullary thyroid carcinoma cells

BACKGROUND

In medullary thyroid carcinoma (MTC), mutations in the RET protooncogene lead to oncogenic transformation. RET activation in other cell types has been shown to cause phosphorylation of the focal adhesion-associated proteins focal adhesion kinase (FAK), paxillin, and p130(CAS). We hypothesized that adhesion-dependent signaling might be deranged in MTC cells.

METHODS

Indirect immunofluorescence was used to label beta(1) integrin, FAK, paxillin, and p130CAS. Rhodamine-labeled phalloidin was used to visualize actin microfilaments. Phosphorylated protein was detected by immunoprecipitation followed by Western blotting for phosphotyrosine. MTC cell invasiveness was quantified using a modified Boyden chamber assay.

RESULTS

Clustering of beta(1) integrin, FAK, paxillin, and p130(CAS) into focal adhesions were not detected in MTC cells under any conditions, although clustering was seen as expected in control HeLa cells. Despite this failure, FAK, paxillin and p130(CAS) were all found to be phosphorylated. Actin microfilaments were generally not seen although in a few cells, small, poorly formed microfilaments could be detected. MTC cells invaded poorly as compared with highly invasive cell lines. However a clear difference was noted between invasiveness on growth factor depleted Matrigel and regular Matrigel.

CONCLUSIONS

In MTC cells, focal adhesions are not seen in response to interaction with extracellular matrix. Consistent with this failure, actin microfilaments are absent or poorly formed and invasion is weak. Despite the absence of focal adhesions, focal adhesion proteins remain phosphorylated, even though in normal cells their signaling activity is dependent on focal adhesion formation. Deranged adhesion-dependent signaling may contribute to MTC pathogenesis.

Medullary breast carcinoma: prognostic implications of p53 expression

Medullary breast carcinoma (MBC) is a rare pathological type of breast cancer. The rate of p53 protein accumulation is higher in MBC than in common invasive ductal carcinoma. Whether this particular feature of MBC influences the outcome after treatment is unknown. We retrospectively analyzed the characteristics, treatment and outcome of 71 patients with MBC treated between 1981 and 1996. The median age was 51 years (range 27-81) and the median clinical tumor size was 25 mm (range 0-70 mm). Breast-conserving treatment was offered when possible: 55 patients had undergone a tumorectomy and radiotherapy while 16 patients had undergone a mastectomy. p53 protein accumulation was determined by immunohistochemistry on paraffin-embedded tumor specimens from 58/71 samples available for this study. The median follow-up for the 56 survivors was 113 months (range 30-241). The 10-year survival and metastasis-free survival rates were 81% and 81.4%, respectively. The local recurrence rate was 16.4%. The two factors predicting outcome were pathological axillary node involvement in the 60 patients who underwent axillary dissection and adjuvant chemotherapy. p53 accumulation was found in 33/58 patients (57%). p53 status was not predictive of survival nor of distant or local recurrences. We confirm that medullary breast carcinoma has a favorable prognosis despite its aggressive pathological features. p53 protein accumulation, found in the majority of MBCs, was not related to outcome.

Co-expression of interleukin-6 (IL-6) and interleukin-6 receptor (IL-6R) in thyroid nodules is associated with co-expression of CD30 ligand/CD30 receptor

Data on the expression of interleukin 6 (IL-6)/interleukin 6 receptor (IL-6R) in thyroid nodules is scarce. Based on our recent data of CD30 ligand (CD30L)/CD30 receptor (CD30) in these nodules and on the knowledge that this signal stimulates IL-6 production in non-thyroid neoplasms, we wanted to evaluate the immunocytochemical expression of these 2 ligand/receptor systems in a large archival series of paraffin-embedded specimens. These specimens included 6 normal thyroids and 130 thyroid nodules. Co-expression of IL-6 and IL-6R in the epithelial (follicular) cells was observed solely in CD30L/CD30 positive nodules: 5/15 (33%) oncocytic adenomas; 6/30 (20%) follicular adenomas which belonged to 2 variants (4/4 microfollicular toxic and 2/2 hyalinizing trabecular); 9/30 (30%) papillary thyroid cancers (PTC), all belonging to the conventional variant. In PTC the proportion of tumor epithelial cells that were IL6 positive was inversely correlated with the pTNM staging (r=-0.549, p=0.01). All 15 follicular cancers (FTC), all 6 anaplastic cancers (ATC) were IL-6/lL-6R negative; 14/15 FTC and 5/6 ATC were CD30L/CD30 negative. In another oncocytic adenoma, another 4 conventional PTC and another 7 non-conventional PTC CD30L/CD30 expression was associated to expression of IL-6 only. IL-6 staining associated to absent expression of CD30L and CD30 was observed in 7 follicular adenomas (all belonging to variants different from toxic and hyalinizing trabecular), 2 oncocytic adenomas, 5 of the 30 colloid nodules and 2 normal thyroids. Of the 6 tumors arising from the parafollicular C cells (medullary thyroid cancer, MTC), all 3 that had metastasized were CD30L/CD30/IL-6 positive and IL-6R negative; only IL-6 expression was lost in both the local and distant metastases. This finding matched the loss of IL-6 expression in one PTC metastasis. All 3 non-metastasized MTC were IL-6/IL-6R negative, and 1/3 was CD30L positive/CD30 negative. We conclude that only in a subset of both benign and malignant thyroid nodules the IL-6/IL-6R signal could be induced by the CD30L/CD30. IL-6 expression is related with aggressiveness in both PTC and MTC. In the normal thyroid tissue, colloid nodules, and another subset of benign and malignant thyroid nodules, IL-6 expression is under control of signals other than CD30L/CD30.

Differential expression of galectin-3 in medullary thyroid carcinoma and C-cell hyperplasia

OBJECTIVE AND DESIGN

Galectin-3 is a beta-galactoside-binding protein that plays a role in cell adhesion and tumour progression. It was shown recently to diagnose malignant follicular thyroid lesions accurately. The reliability of this marker in the differential diagnosis between medullary thyroid carcinoma and C-cell hyperplasia was studied by immunohistochemistry.

PATIENTS

Tissue specimens were obtained from 34 patients belonging to families with medullary thyroid carcinoma who underwent prophylactic thyroidectomy for RET gene mutation and/or abnormally increased plasma calcitonin levels.

RESULTS

Galectin-3 was expressed in 23 of 25 cases of medullary thyroid carcinoma and in none of the nine cases of C-cell hyperplasia only, giving a sensitivity of 92% and a specificity of 100% for the diagnosis of carcinoma. A significant association was found between higher galectin-3 expression and occurrence of lymph node metastases (P < 0.05).

CONCLUSIONS

Galectin-3 is a reliable diagnostic marker of medullary thyroid carcinoma, and its use may provide relevant information for prognosis and therapy.

Renal medullary carcinoma: clinical, pathologic, immunohistochemical, and genetic analysis with pathogenetic implications

OBJECTIVES

To investigate the pathologic, clinical, and genetic features of renal medullary carcinomas (RMCs) in search of clues to their pathogenesis.

METHODS

We analyzed 40 RMCs for clinical features, for immunohistochemical expression using a panel of markers, and for genetic changes using comparative genomic hybridization.

RESULTS

Patients presented at 5 to 32 years of age, and 82% were African American. All patients tested had sickle cell trait or disease. Seven patients presented with suspected renal abscess or urinary track infection without a clinically recognizable mass. Of the 15 tumors able to be analyzed, all were positive for epithelial markers CAM 5.2 and epithelial membrane antigen. All were negative for high-molecular-weight cytokeratin 34betaE12. Cytokeratins 7 and 20 and carcinoembryonic antigen were heterogeneous and variable. Ulex was focally positive in a minority of cases. Eight of 12 tumors showed significant positivity for TP53 protein (greater than 25% nuclear positivity). All tumor tested (n = 8) were strongly positive for vascular endothelial growth factor and hypoxia inducible factor. Of nine tumors analyzed for genetic gains and losses using comparative genomic hybridization, eight showed no changes and one showed loss of chromosome 22. Survival ranged from 2 weeks to 15 months (mean 4 months).

CONCLUSIONS

These findings suggest that RMC is clinically and pathologically distinct from collecting duct carcinoma. The hypothesis that chronic medullary hypoxia secondary to hemoglobinopathy may be involved in the pathogenesis of RMC is suggested by strong vascular endothelial growth factor and hypoxia inducible factor expression and positivity for TP53.

Cholecystokinin-B/Gastrin receptor-targeting peptides for staging and therapy of medullary thyroid cancer and other cholecystokinin-B receptor-expressing malignancies

The high sensitivity of the pentagastrin stimulation test in detecting primary or metastatic medullary thyroid cancer (MTC) suggests a widespread expression of the corresponding receptor type on human MTC. Indeed, autoradiographic studies demonstrated cholecystokinin (CCK)-B/gastrin receptors not only in more than 90% of MTCs, but also in a high percentage of small-cell lung cancers, stromal ovarian tumors, and potentially a variety of other tumors, including gastrointestinal adenocarcinomas, neuroendocrine tumors, and malignant glioma. The aim of our work was to develop and systematically optimize suitable radioligands for targeting CCK-B receptors in vivo and to investigate their role in the staging and therapy of MTC and other CCK-B receptor expressing malignancies. For this purpose, a variety of CCK/gastrin-related peptides, all having in common the C-terminal CCK-receptor binding tetrapeptide sequence-Trp-Met-Asp-PheNH(2) or derivatives thereof, were investigated. They were members of the gastrin or cholecystokinin families or possessed characteristics of both, which differ by the intramolecular position of a tyrosyl moiety. Their stability and affinity were studied and optimized in vitro and in vivo; their biodistribution and therapeutic efficacy were tested in preclinical models. Best tumor uptake and tumor to nontumor ratios were obtained with members of the gastrin family, because of their superior selectivity and affinity for the CCK-B receptor subtype. Radiometal-labeled derivates of minigastrin showed excellent targeting of CCK-B receptor expressing tissues in animals and healthy human volunteers. Preclinical therapy experiments in MTC-bearing animals showed significant antitumor efficacy. In a subsequent clinical study, 45 MTC patients with metastatic MTC were investigated; 23 had known and 22 had occult disease. CCK-B receptor scintigraphy was performed with (111)In-diethylenetriamine pentaacetic acid-d-Glu(1)-minigastrin. The normal organ uptake was essentially confined to the stomach (and, to a lesser extent, to the gallbladder and, in premenopausal women, to normal breast tissue) as a result of CCK-B receptor specific binding and to the kidneys, as excretory organs. All tumor manifestations known from conventional imaging were visualized as early as 1 hour postinjection, with increasing tumor to background ratios over time; at least 1 lesion was detected in 20 of 22 patients with occult disease (patient-based sensitivity, 91%). Among them were local recurrences and lymph node, pulmonary, hepatic, splenic, and bone (marrow) metastases. Eight patients with advanced metastatic disease were injected in a dose-escalation study with potentially therapeutic activities of a (90)Y-labeled minigastrin derivative at 4 to 6-week intervals (30-50 mCi/m(2) per injection for a maximum of 4 injections). Hematologic and renal toxicities were identified as the dose-limiting toxicities at the 40 and 50 mCi/m(2) levels. Two patients experienced partial remissions, and 4 experienced stabilization of their previously rapidly progressing disease. These data suggest that CCK-B receptor ligands may be a useful new class of receptor-binding peptides for diagnosis and therapy of a variety of (CCK-B receptor expressing) tumor types. They allow for sensitive and reliable staging of patients with metastatic MTC. Initial therapeutic results are promising, but nephrotoxicity is a major concern to be solved.

An immunohistochemical survey of nine cases of medullary carcinoma of thyroid including reactivity for Cox-1 and Cox-2 enzymes

There has been much recent investigation of the cyclooxygenase (Cox) enzymes in tumor biology, but, to our knowledge, no study has yet been published describing Cox activity in medullary carcinoma of the thyroid (MTC). Nine cases of MTC from the past 10 yr were retrieved from our hospital archives. Slides cut from formalin-fixed paraffin-embedded tumor tissue from these cases were assessed for the activities of Cox-1 and Cox-2 enzymes by immunohistochemistry as well as by a battery of immunohistochemical stains for intermediate filaments, peptide hormone, and proliferation and promoter antigens. The staining reactions were semiquantitatively assessed and scored for comparison with each other as well as with each patient s clinical presentation and course. Staining for Cox-1 and Cox-2 enzymes was present only in tumorous tissue, not in nontumorous thyroid tissue or C-cells. Cox-2 staining was not consistently increased over Cox-1 staining; however, Cox-2 staining bore statistically significant correlations with the expression of low molecular weight keratin, thyroid-transforming factor-1, topoisomerase, and MIB1. Hyperplastic C-cells from patients with diverse physiologic conditions and from three patients with C-cell hyperplasia accompanying medullary carcinoma or multiple endocrine neoplasia type IIa showed no reactivity for the Cox antibodies. It appears that Cox enzyme immunoreactivity is present only in the neoplastic C-cells of medullary carcinoma, but with variable expression. A practical application of the preceding finding might involve the use of Cox staining to distinguish invasive medullary carcinoma cells from hyperplastic C-cells.

Sporadic versus familial medullary thyroid microcarcinoma: a histopathologic study of 50 consecutive patients

By means of calcitonin screening programs, sporadic and hereditary medullary thyroid carcinoma (MTC) can be detected at an early stage. We investigated the histopathologic findings of 16 familial (mean age 32 +/- 21 years, female/male ratio 1.6:1) and 34 sporadic (mean age 58 +/- 15 years; female/male ratio 2.4:1) MTCs with stage T1 comparatively. Patients with hereditary tumors were younger. Hereditary tumors were more often found multifocal (13 of 16 vs 3 of 34; p < 0.001), bilateral (11 of 16 vs 3 of 34; p < 0.001), displaying desmoplastic stroma (14 of 16 vs 19 of 34; p = 0.02), and accompanied by C cell hyperplasia (16 of 16 vs 24 of 34; p = 0.01), but all of these factors were present in some sporadic patients. Only tumors with desmoplastic stroma showed lymph node metastasis, which was observed in eight of the 50 patients. After surgery all patients showed permanent normalization of calcitonin levels. We conclude that 1) morphologic parameters considered to indicate familial MTC risk are of no value in the individual patient, 2) many sporadic MTCs develop on the background of CCH, 3) tumors with desmoplastic stroma are more likely to develop lymph node metastasis, and 4) early detection of MTC permits curative surgery in the majority of patients.

Immunohistochemical detection of somatostatin receptor types 1-5 in medullary carcinoma of the thyroid

BACKGROUND

We have analysed the distribution of the five somatostatin receptors (sst1-5) by immunohistochemistry in a large retrospective series of 51 medullary carcinoma of the thyroid (MCT) specimens and correlated the pattern of sst expression with expression of somatostatin (SRIF) peptide, tumour pathology and clinical outcome.

MEASUREMENTS

Immunohistochemistry was performed with rabbit polyclonal antipeptide antibodies directed against the extracellular domains or cytoplasmic tail of human (h) sst1-5. SRIF immunoreactivity was investigated in parallel paraffin sections.

RESULTS

Eighty-five percent of the tumours were positive for one or more sst, localized to both tumour cells as well as surrounding peritumoural structures, especially blood vessels. Forty-nine percent of the tumours were positive for sst1, 43% for sst2, 47% for sst3, 4% for sst4, and 57% for sst5. Fifty-one percent of tumours expressed one or two sst subtypes; 33% were positive for three or more sst isoforms. All five sst receptors were detected in only two cases. Tumours expressing octreotide sensitive subtypes (sst2,3,5) accounted for 75% of the series. 50% of the tumours co-expressed SRIF suggesting tumour cell regulation by endogenous SRIF via paracrine/autocrine circuits. There was no correlation between sst1-5 expression and age, sex, tumour size or stage, histological type or clinical outcome. Simultaneous analysis of primary tumour and lymph node metastases revealed a similar pattern of sst immunoreactivity indicating that sst expression is not modified in the course of disease progression.

CONCLUSIONS

With the exception of sst4, medullary carcinoma of the thyroid display a rich but heterogeneous expression of sst subtypes. Immunohistochemical typing of sst receptor expression using specific antireceptor antibodies represents an ideal approach for characterizing sst subtype expression in medullary carcinoma of the thyroid for optimizing receptor targeted diagnosis and therapy with somatostatin analogs.

Simultaneously occurring liver metastases of pheochromocytoma and medullary thyroid carcinoma--a diagnostic pitfall with clinical implications for patients with multiple endocrine neoplasia type 2a

Malignant pheochromocytoma is an exceptional complication in patients with Multiple Endocrine Neoplasia Type 2a (MEN2a). In this paper, we report on a 53-year-old male patient with an evident RET gene germline mutation, who simultaneously developed hepatic metastases of medullary thyroid carcinoma (MTC) and pheochromocytoma. Comprehensive immunohistochemical investigations were performed to elaborate markers which could be useful for differentiating between MTC metastases and pheochromocytoma, respectively. Calcitonin and CEA, in particular cytokeratins and trefoil factor family 1 (TFF1), were detectable exclusively in MTC, whereas all the other markers revealed a comparable expression in both MTC and pheochromocytoma. The only clues that could indicate a potential malignant course were size, a lack of sustentacular cells and hyaline globules, and a focal spindle cell pattern in pheochromocytoma. Owing to a wide agreement in cellular differentiation and a lack of specific, routinely applicable markers for pheochromocytomas, a comprehensive and goal-directed immunohistochemistry is required to rule out pheochromocytoma metastasis in patients with MEN2a. A misinterpretation could lead to harmful clinical complications, as shown in the present case.

Clinicopathological value of somatostatin type 2A and estrogen receptor immunoreactivity in human breast carcinoma

Somatostatin type 2A (sstr2A) and estrogen receptor (ER) are interrelated regulatory receptors present in normal breast epithelium and in a population of breast carcinomas. ER mediates growth stimulatory effects of estrogens whereas sstr2A mediates growth inhibitory actions of somatostatin. However, much work has been devoted to elucidate the biological role of ER, little is known about sstr2A in breast cancer. In the present study we examined immunoreactivity of sstr2A and ER in 64 breast carcinomas in correlation with tumor size and histological grade (HG), presence of lymph node metastasis (LNM), Nottingham prognostic index (NPI), and the patients' age. ER and sstr2A immunoreactivity were present in 78% and 63% of the breast carcinomas, respectively. Ninety percent of tumors immunoreactive for sstr2A were simultaneously immunoreactive for ER. ER immunoreactivity correlated significantly with lower HG (p = 0.03) and better NPI (p = 0.02). sstr2A immunoreactivity correlated significantly with lower HG (p = 0.012) but not with NPI (p = 0.26). There was no correlation of sstr2A immunoreactivity and tumor size, patients' chronological age or LNM. The results confirm prognostic value of ER immunohistochemistry in breast carcinoma. However sstr2A cannot substitute ER for prognostic evaluation, sstr2A immunoreactivity being significantly associated with lower HG seems to represent an independent prognostic factor in breast carcinoma.

High prevalence of RET tyrosine kinase activation in Mexican patients with papillary thyroid carcinomas

RET/PTC oncogene expression is restricted to papillary thyroid carcinomas (PTC). At least three forms of this oncogene have been described. These are generated by the rearrangement of the 5'-terminal region of different expressed genes with the tyrosine-kinase (TK) domain of the ret proto-oncogene. Several studies showing the correlation between the expression of this oncogene, clinical outcome, and histological subtypes have been published. Thirty-five paraffin-embedded PTC samples from patients without a history of radiation exposure were studied. Immunohistochemistry (IHC) and in situ hybridization (ISH) were used to determine a possible correlation between RET activation, clinical outcome, and tumor subtype. Almost half of the studied cases presented with tumoral extension or metastases. Ret gene transcripts and protein were found in all PTC variants as well as in their corresponding metastases. In contrast, none of the follicular adenomas, goiters, or normal follicular cells from the thyroid gland showed evidence of ret activation. We observed a high frequency of ret expression in PTCs, suggesting that ret activation is a common event in nonradiation-related PTC from Mexican patients.

The helix-loop-helix transcription factor, Id-1, is overexpressed in medullary thyroid cancer

BACKGROUND

The Id-1 helix-loop-helix protein inhibits differentiation and enhances cell proliferation. It is required for cell cycle progression. The Id-1 gene is highly expressed in a variety of tumor-derived cell lines. It increases after mitogen stimulation and is overexpressed in some human neoplasms. Therefore, we hypothesized that the Id-1 gene may play a role in medullary thyroid carcinogenesis.

METHODS

The expression of the Id-1 protein in human medullary thyroid cancer (MTC) and the corresponding normal thyroid tissue was determined by Id-1 immunohistochemistry. In a human MTC cell line (TT), the effects of growth stimulation and redifferentiation on Id-1 expression were determined by Northern blot analysis.

RESULTS

Id-1 immunostaining intensity in 9 MTC samples (6 sporadic, 2 familial, and 1 MEN 2A) was moderate to strong. However, it was absent or faint in the corresponding normal thyroid tissue. The Id-1 protein was significantly overexpressed in MTC compared with corresponding normal thyroid tissue on the basis of the percentage of positive cells and immunostaining intensity (P =.002). In the TT cell line, Id-1 messenger RNA (mRNA) expression was increased 4-fold after growth stimulation with serum. Phorbol ester (which induces redifferentiation in the TT cell line) downregulated Id-1 mRNA expression.

CONCLUSIONS

Id-1 is overexpressed in MTC. The Id-1 gene may play a role in the regulation of MTC differentiation and proliferation.

Normal preoperative calcitonin levels do not always exclude medullary thyroid carcinoma in patients with large palpable thyroid masses

Medullary thyroid carcinoma (MCT) is a sporadic or familial tumor of the parafollicular or C-cells that secretes calcitonin. The sporadic form usually presents with a palpable thyroid nodule or cervical adenopathy, by which time basal calcitonin levels are almost always elevated. Without special stains, fine-needle biopsy may fail to detect MCT. Recently, several investigators have recommended routine measurement of serum calcitonin in patients with nodular thyroid diseases for the preoperative diagnosis of MCT. A 31-year-old woman had a large palpable MCT with normal calcitonin and carcinoembryonic antigen levels before surgery. Fine-needle aspiration (FNA) demonstrated atypical cells but was not diagnostic of MCT. Pathology revealed a 3 x 4.5 x 2.3 cm MCT. Immunochemical stains showed immunoreactivity for calcitonin and synaptophysin, but no immunoreactivity to thyroglobulin. Postoperative basal and pentagastrin-stimulated calcitonin levels have remained undetectable without evidence of recurrent cancer. We have evaluated six other patients with MCT that were palpable. They had preoperative calcitonin levels ranging from 322-50,032 pmol/L. This unique case of a woman with a 4.5-cm MCT and normal preoperative calcitonin levels, emphasizes the need for careful clinical evaluation and FNA biopsy in managing patients with nodular thyroid disease.

Cytologic diagnosis of medullary carcinoma of the thyroid gland

The cytomorphologic features in fine-needle aspiration (FNA) biopsies from 91 histologiacally verified medullary carcinomas of the thyroid (MCT) were investigated. FNA was able to diagnose neoplasms with indications of surgical removal in 98.9% of cases and moreover, was accurate in specific tumor typing in 89% of cases. The most important cytologic criteria of MCT with FNA are: dispersed cell-pattern of polygonal or triangular cells, azurophilic cytoplasmic granules, and extremely eccentrically placed nuclei with coarse granular chromatin and amyloid. These and other cytologic features of MCT are discussed in detail. Fourteen cases of thyroid tumors originally diagnosed as MCT by cytology are illustrated to discuss the differential diagnosis of MCT and its potential pitfalls. If MCT is cytologically presumed but amyloid and azurophilic cytoplasmic granules are not demonstrated, the use of immunostaining is necessary for a correct tumor typing. The application of immunocytochemistry in MCT is discussed.

Sustentacular cells in sporadic paraganglioma-like medullary thyroid carcinoma: report of a case with diagnostic and histogenetic considerations

Sustentacular cells (SCs) are glial supporting cells of the fetal, adult normal, and neoplastic extra and adrenal human chromaffin cell lineage. SCs have also been identified in some cases of medullary thyroid carcinoma (MTC), raising both diagnostic and histogenetic problems. We report a rare case of a sporadic paraganglioma-like variant of MTC showing numerous S-100 protein and glial fibrillar acid protein (GFAP) positive SCs encircling neoplastic cells in a nesting (Zellballen) pattern similar to that observed in paragangliomas or pheochromocytomas. Although stromal amyloid deposits were only focally detected, diagnosis was immunohistochemically confirmed by immunoreactivity of the neoplastic cells for cytokeratin, CEA, calcitonin, chromogranin A, neuron-specific-enolase, and synapthopysin. As for the histogenesis of SCs, if we assume that MTC is a neural crest-derived tumor, it is likely that these cells reflect the ability of the common precursor cell to differentiate towards a sustentacular-type glial cell lineage in addition to the typical neuroendocrine one. This viewpoint is supported by the evidence that rare cases of MTC may contain neoplastic or supporting cells showing a multidirectional differentiation (usually neuroendocrine and melanocytic) that recapitulates the different cell lineages arising from the developing neural crests.

Expression of Pax-8, p53 and bcl-2 in human benign and malignant thyroid diseases

BACKGROUND

Immunohistochemical expression of the transcription factor Pax-8 in human thyroid diseases has never been investigated. The relationship between Pax-8, bcl-2 and p53 in thyroid neoplasms is also matter of interest.

MATERIALS AND METHODS

Seventy-three thyroid tissue samples were evaluated for the expression of Pax-8, p53 and bcl-2 using the immunoperoxidase technique. The series included 11 follicular adenomas, 11 goitres, 23 papillary carcinomas, 16 follicular carcinomas, 6 undifferentiated carcinomas and 6 medullary carcinomas.

RESULTS

The percentage of Pax-8 positive cells ranged from 14.9 to 27.1% and 10.1 to 39% in goitres and follicular adenomas, respectively. Among differentiated carcinomas, follicular histotype showed a Pax-8 immunoreactivity ranging from 0 to 26.5% of the neoplastic cells whereas in papillary carcinomas the percentage of positive cells ranged from 0 to 16.8%. None out of the six undifferentiated carcinomas showed Pax-8 immunoreactivity. The same negative pattern was noticed in medullary carcinomas. A statistically significant difference in Pax-8 expression was observed between non-malignant and malignant diseases (p < 0.0001). A different reactivity for Pax-8 was also noticed between differentiated carcinomas and undifferentiated carcinomas (p = 0.07). None of the benign tissues stained for p53 whereas among malignant specimens different percentages of p53 expression were observed with all undifferentiated carcinomas expressing the highest positivity (range 24.1-88.6%). Finally, when a combined analysis of bcl-2 and Pax-8 reactivity was carried out, some carcinomas proved to be Pax-8 negative and bcl-2 positive whereas others showed a similar immunoreactive pattern for both Pax-8 and bcl-2.

CONCLUSIONS

Pax-8 is mainly expressed in benign rather than in malignant thyroid diseases and, among neoplasms, differentiated carcinomas express Pax-8 more frequently than undifferentiated carcinomas. An inverse pattern was observed for p53. Bcl-2 seems to be partially related to Pax-8 expression. However, a Pax-8 independent bcl-2 expression is also evident.

Expression of cytokeratin 20 in thyroid carcinomas and peripheral blood detected by reverse transcription polymerase chain reaction

We investigated a nested reverse transcriptase polymerase chain reaction (RT-PCR) system to detect CK20 mRNA in thyroid carcinomas, benign thyroid diseases and peripheral blood to improve diagnosis of thyroid carcinoma and to detect disseminated tumour cells. Frozen tissue samples of 46 thyroid carcinomas and 30 benign thyroid diseases (14 multinodular goiters, 14 follicular adenomas, two Hashimoto's thyroiditis) were obtained intraoperatively. Preoperative blood samples were drawn from 31 patients with thyroid cancer, nine patients with benign thyroid disorders and 20 healthy volunteers. Nine out of nine medullary, 9/12 follicular, 7/19 papillary and 2/6 anaplastic carcinomas expressed CK20 transcripts. CK20 mRNA was undetectable in 30 tissue sections of benign thyroid diseases. Circulating tumour cells were found in the blood of 3/8 patients with medullary carcinoma, 2/8 patients with follicular carcinoma, 2/11 patients with papillary carcinoma and 1/4 patients with an anaplastic carcinoma. Nine blood samples of patients with benign thyroid diseases and 20 healthy volunteers tested negative. For the first time CK20 mRNA could be detected in tissue sections of thyroid carcinomas and peripheral blood samples of patients with thyroid cancer. It was not detectable in benign thyroid diseases. Our results therefore strongly suggest that CK20 RT-PCR assays may improve the diagnosis of thyroid carcinoma and is able to detect circulating tumour cells in peripheral blood of thyroid carcinoma patients.

Is medullary thyroid cancer predictable? A prospective study of 86 patients with abnormal pentagastrin tests

BACKGROUND

The aim of this prospective study was to distinguish biochemically between C-cell hyperplasia (CCH) and medullary thyroid cancer (MTC) before surgery.

METHODS

Eighty-six consecutive patients with an abnormal stimulated calcitonin level (> 100 pg/mL) underwent thyroidectomy and lymph node dissection. In sporadic MTC, histopathologic findings and postoperative biochemical outcomes were documented prospectively and correlated with preoperative basal and stimulated calcitonin levels.

RESULTS

Analysis of variance revealed a highly significant difference in basal/stimulated calcitonin levels (P < .0001), with a comparison of CCH (n = 39 patients) and sporadic MTC (n = 38 patients). With a comparison of sporadic MTC N0 M0 (n = 25 patients) and N1 M0/1 (n = 12 patients), the basal calcitonin level was significantly different (P < .05). There was a close correlation between the n-log of basal/stimulated calcitonin level and the n-log of the tumor volume; there were also different distributions of the n-log of basal/stimulated calcitonin level among CCH, MTC N0, and MTC N1. Assuming that a basal calcitonin level of more than 64 pg/mL and/or a stimulated calcitonin level of more than 560 pg/mL implies MTC, 31 of 38 patients with sporadic MTC were detected before surgery. Three patients were predicted false positive (neoplastic CCH). Patients with stimulated calcitonin levels of less than 129 pg/mL had CCH only. Patients with basal calcitonin levels of less than 22 pg/mL and sporadic MTC (7/38 patients) were node negative.

CONCLUSIONS

All patients with abnormal pentagastrin tests showed C-cell pathologic evidence. Sporadic MTC was predicted in 81% of the patients; CCH or N0 was predicted in 36% of the patients. Central neck dissection is recommended to avoid difficult reoperations. Lateral neck dissection is possible "on demand."

P-cadherin expression in breast carcinoma indicates poor survival

BACKGROUND

The cadherin family of cell-cell adhesion molecules and their associated proteins, the catenins, are essential to embryonic development and the maintenance of adult tissues. During development, the homotypic interaction of a particular cadherin with an identical cadherin expressed on a neighboring cell results in the sorting of cells to form distinctive tissues. Cadherins are believed to be tumor suppressors, and their altered expression and function have been associated with tumor development.

METHODS

The authors examined the expression of P-cadherin, E-cadherin, and N-cadherin, and alpha-catenin and beta-catenin in 183 cases of invasive breast carcinoma by immunohistochemistry on paraffin sections using specific antibodies and a steam-based antigen retrieval method.

RESULTS

P-cadherin was positive in 95 cases and negative in 88 cases of breast carcinoma. Positive P-cadherin expression in breast carcinoma showed a strong correlation with poor patient prognosis. Five years after surgery, 90% of the patients with P-cadherin negative tumors were alive in contrast to only 59% of patients with P-cadherin positive tumors. The difference in survival reached statistical significance (P = 0.0001) as early as 2 years after surgical treatment. Expression of N-cadherin, alpha-catenin, and beta-catenin did not correlate with patient survival. Multivariable statistical analyses of the data showed that expression of P-cadherin was independent of tumor size and lymph node metastases, but correlated inversely with estrogen/progesterone receptor status. In ductal carcinomas, positive P-cadherin expression correlated with a higher histologic grade. In contrast, expression of E-cadherin was low in high grade ductal carcinomas but negative tumors were uncommon. Negative or low E-cadherin expression did not correlate with poor survival. In lobular carcinomas, E-cadherin expression frequently was negative or low, and P-cadherin always was negative.

CONCLUSIONS

Expression of P-cadherin in breast carcinoma is associated strongly with poor survival and constitutes an independent prognostic predictor. P-cadherin expression is a better indicator of clinical outcome than alterations in the expression of E-cadherin, N-cadherin, alpha-catenin, or beta-catenin.

[111In-pentetreotide in the study of tumors expressing somatostatin receptors]

The usefulness of 111In-pentetreotide scintigraphy in the diagnosis of neuroendocrine tumors was evaluated.

MATERIAL AND METHOD

39 patients with clinical or biochemical suspicion of neuroendocrine tumors were studied. 29 patients underwent surgery and diagnosis was confirmed by anatomopathology findings (7 mixed tumors, 6 carcinoids, 3 insulinomas, 3 pheocromocytomas, 2 glucagonomas, 2 medullary thyroid carcinomas, 1 gastrinoma and 5 metastatic lesions). In 10 patients who did not undergo surgery, the diagnostic criteria were based on a 6 month follow-up. 111In-pentetreotide scintigraphy and computed tomography (CT) were performed in all of the patients.

RESULTS

The scintigraphy correctly detected 58% of the primary tumors while the CT was positive in only 45% of the cases. Both techniques detected metastasis in 5 patients.

CONCLUSION

111In-pentetreotide scintigraphy is a useful technique to diagnose those tumors that have somatostatin receptors. In our series, the sensitivity of this method was higher than the CT.

[Renal medullary carcinoma, a new clinico-pathological entity. Immunohistochemical, ultrastructural, flow cytometric and cytogenetic study of a case]

The renal medullary carcinoma is a rare tumor. We report a case in a black patient with sickle cell trait. The tumor was located in the lower pole of the left kidney. It had a tubular and microcystic architecture. It was composed of large eosinophilic cells with vesicular nuclei containing prominent nucleoli, in a desmoplastic and inflammatory stroma. By immunohistochemistry, the tumoral cells were positive for cytokeratin and Ulex europaeus lectin. Electron microscopy revealed small intracytoplasmic lumina with microvilli. The flow cytometric study showed DNA-multiploidy. The cytogenetic study revealed tetraploidy without structural abnormality. The renal medullary carcinoma is often reported in young black patients with sickle cell trait. Its microscopic, immunohistochemical and ultrastructural features favor its identification as a particular variety of Bellini duct carcinoma. Its link with sickle cell trait has to be defined.

E-cadherin and beta-catenin expression in breast medullary carcinomas

The initial step of cancer invasion and metastasis is the escape of tumour cells from the primary site, involving disruption of normal cell-cell adhesion and E-cadherin (E-cad) and beta-catenin (beta-cat) down-regulation, as shown in various types of human malignancies including breast carcinomas. Medullary carcinomas are high grade and poorly differentiated tumours with syncytial typical pattern, and prognosis unexpectedly better than that in high grade breast carcinomas. In a series of 55 breast typical medullary carcinomas diagnosed according to the strict use of Ridolfi et al (Cancer 40: 1365-1385, 1977) criteria, E-cad and beta-cat were investigated using quantitative (SAMBA 2005 system) immunocytochemical assays on frozen sections. Results were compared to that obtained on paraffin sections and in a series (n=55) of grade 3 ductal carcinomas. It was shown that medullary carcinomas significantly (p<0.001) expressed more E-cad and beta-cat than grade 3 ductal carcinomas. E-cad and beta-cat correlated with high expression of P53, of c-erbB, and of Ki-67 antigens, and with lack of hormone receptors antigenic sites (p<0.001). It was concluded that favourable prognosis and syncytial pattern of typical breast medullary carcinomas likely results, at least partly, from a particular expression of cell-cell adhesion molecules, significantly limiting tumour growth and efficiently mastering the tumour cell dissemination, opposing to high proliferative activity (grade 3).