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PubMed1998

5-Fluorouracil, dacarbazine, and epirubicin in the treatment of patients with neuroendocrine tumors.

BACKGROUND: For patients with surgically untreatable neuroendocrine tumors (NETs), the optimal therapeutic approach remains undefined. Somatostatin analogs and interferons have failed to control neoplastic growth, and chemotherapy has been only moderately more effective. The authors' previous study of the combination of 5-fluorouracil (FU), dacarbazine (DTIC), and epirubicin (EPI) (the FDE regimen) documented good tolerability, but the results for tumor growth control were disappointing. In an attempt to improve these results, the authors conducted a preliminary trial of an intensified FDE regimen (FU 500 mg/m2 administered intravenously [i.v.], DTIC 200 mg/m2 i.v., and EPI 30 mg/m2 i.v. on Days 1, 2, and 3 every 3 weeks). METHODS: Thirty NET patients (15 male, 15 female; median age, 55 years; age range, 19-72 years) were enrolled, none of whom had previously been given chemotherapy. The histologic types of disease were gastroenteropancreatic (GEP) tumors (n = 21, 6 carcinoid tumors and 15 pancreatic NETs), other carcinoid tumors (n = 3), other NETs (n = 4), medullary thyroid carcinoma (MTC) (n = 1), and Merkel cell carcinoma (n = 1). Six patients had a syndrome related to endocrine hypersecretion. One hundred fifty-four therapy cycles were delivered (median, six per patient), and all patients could be evaluated for response on the basis of intent-to-treat analysis. RESULTS: There were 9 objective responses: 2 complete responses (in 1 patient with Merkel cell carcinoma and 1 with pancreatic NET) and 7 partial responses (in 3 patients with pancreatic NETs, 2 with other NETs, 1 with GEP carcinoid tumor, and 1 with MTC). The median duration of response was 10 months (range, 5+ to 24+ months). No reduction in symptoms was achieved among the six patients with endocrine hypersecretion syndrome. Levels of urinary 5-hydroxyindoleacetic acid and serum chromogranin A were decreased in 50% and 14% of patients, respectively, who presented with abnormal baseline values. Treatment toxicity was acceptable and included nausea and vomiting, alopecia, leukopenia, and mucositis. CONCLUSIONS: This trial demonstrated that the FDE regimen may be at least as effective as other systemic regimens. Comparison of this experience with the authors' previous trial revealed a noteworthy increase in the activity of the intensified regimen, especially in GEP NETs (the most chemoresistant tumors). Continued clinical research to improve these results is highly justified.

Adult↗
PubMed2003

Effects of gadolinium and tetrodotoxin on the response of slowly adapting type I mechanoreceptors to mechanical stimulation in frog dorsal skin.

To elucidate the excitatory mechanism of mechanoreceptors innervating the frog skin, we examined the effects of gadolinium (Gd3+) and tetrodotoxin (TTX) on the response of single-unit activity of slowly adapting type I mechanoreceptors to mechanical stimulation topically applied to the receptive field (RF). Recordings were made from 46 fibers responding to mechanical stimulation with von Frey hairs, which caused an irregular firing pattern with slow adaptation. Application of a mechanically gated channel blocker, Gd3+ (30 microM), and a Na+ channel blocker, TTX (3 microM), caused the suppression of discharge rates, which was characterized by the conversion of a slowly adapting to a rapidly adapting discharge pattern. The administration of a high-voltage-activated (HVA) Ca2+ channel blocker, Cd2+ (100 microm), inhibited the unit discharge and caused the conversion of a slowly adapting to a rapidly adapting discharge pattern. Tonic discharges evoked by anodal electrical stimulation were inhibited by the application of Gd3+ or TTX. Electron microscopic examination showed that the cytoplasm of Merkel cells seen in the RF contained numerous Merkel granules. These results suggest that the excitatory mechanism of frog cutaneous mechanoreceptors may be mediated by the activation of Gd(3+)-sensitive stretch-activated channels in the Merkel cell-neurite complex, which are related to the Na+ influx via voltage-gated Na+ channels and/or the Ca2+ influx through HVA Ca2+ channels.

Action Potentials↗
PubMed2003

5-HT2 and 3 receptor antagonists suppress the response of rat type I slowly adapting mechanoreceptor: an in vitro study.

Previous experiments have shown an increase in rat type I mechanoreceptor responsiveness during arterial serotonin (5-hydroxytryptamine) infusion and the presence of serotonin immunostaining in Merkel cells. The current findings demonstrate that the 5-HT(2) antagonists ritanserin and ketanserin, as well as the 5-HT(3) antagonist MDL 72222, reduce type I response to a standardized mechanical stimulus in an in vitro skin preparation. In addition, ritanserin blocked the enhancement of type I response produced by 5-HT. These experiments suggest that serotonin is released during mechanical distortion of the Merkel cell membrane and alters action potential generation by the type I ending. In addition, it is possible that serotonin, released from outside the type I complex, influences mechanoreceptor responsiveness. For example, serotonin generated during inflammatory events could enhance type I response to mechanical stimulation and thereby increase symptoms of mechanical allodynia.

Action Potentials↗
PubMed2005

Fibroepithelioma of pinkus is a fenestrated trichoblastoma.

Pinkus described "pre-malignant fibroepithelioma" as a proliferation that gave rise to many tiny basal cell carcinomas within each lesion. Later authors have generally considered it to be an unusual variant of basal cell carcinoma (BCC). The delineation of trichoblastoma as the general term for the benign counterpart of BCC raises the possibility that the fibroepithelioma of Pinkus (FEP) would be better classified under that rubric. To address this subject, we examined the records of 114 patients with FEP for body site, age and sex distribution, and sections from 75 lesions. All FEP examined show a blunt interface with the underlying dermis (where one could be seen), differentiation toward follicular bulbs and papillae, and large areas of cellular stroma. FEP has a slight female preponderance in contrast to BCC, which is more common in males. Unlike the common types of BCC, FEP has an overwhelming predilection for the trunk and extremities, and only 5% of tumors are set in a dermis with significant amounts of solar elastosis. Next, FEP, BCC, and FEP with BCC-like areas were stained with MIB-1 (to assess proliferation), p53 (an oncogene product), and CK20 (a Merkel cell marker) antisera. FEP shows a low level of staining for p53 and MIB-1, in contrast to conventional BCCs that over-express these markers. FEP also shows retention of Merkel cells, a characteristic of benign neoplasms with follicular germinative differentiation but not in general of BCC. The BCC-like areas in some FEP tumors reflect these staining tendencies with less striking differences. Given the contrast between FEP and BCC with respect to site of occurrence, relationship to sun damage, histopathologic features, and immunohistochemical studies, it appears that FEP more closely resembles trichoblastoma than BCC.

Adolescent↗
PubMed1985

Anterograde axonal transport and intercellular transfer of WGA-HRP in trigeminal-innervated sensory receptors of rat incisive papilla.

The ultrastructure and identification of WGA-HRP-labeled sensory receptors in the rat incisive papilla (the most anterior part of hard palate) were studied using semiserial thin sections. Various sensory receptors were organized according to three locations: dome region (ventral), chemosensory corpuscle region (medial to orifice of incisive canal), and lateral labium (apposing the incisive canal). In the dome region, the sensory receptors were localized in three sensory zones that were associated with surface ridges (one medial and two lateral). In each of these zones, intraepithelial receptor axons and Merkel receptors occurred in the epithelium, while simple unencapsulated corpuscles, glomerular-Meissner corpuscles, and incisive (encapsulated) corpuscles occurred in the lamina propria. In the chemosensory corpuscle region, chemosensory corpuscles and intraepithelial receptor axons were located in the epithelium, and incisive corpuscles were present in the lamina propria. In the lateral labium, only intraepithelial receptor axons were prominent. In all these sensory receptors, the preterminal axons and axon terminals were labeled with the tracer protein. In addition, some nonneuronal cells closely associated with the axon terminals were selectively labeled, e.g., terminal Schwann cells, lamellar Schwann cells, Merkel cells, corpuscular basal cells and chemosensory cells. Other adjacent cells were not labeled, e.g., unspecialized epithelial cells, capsular cells, corpuscular sustentacular cells, and fibroblasts. In both labeled axons and cells, WGA-HRP was incorporated into vesicles, tubules, and vacuolar organelles. The specific intercellular transfer of tracer protein may indicate trophic interactions between axon terminals and support cells in sensory receptors. The specific organization of multiple sensory receptors in the rat incisive papilla may provide a useful alternative system for studying somatosensory physiology.

Animals↗
PubMed1994

Localization of nerve growth factor (NGF) and low-affinity NGF receptors in touch domes and quantification of NGF mRNA in keratinocytes of adult rats.

Touch domes are clearly delineated mechanoreceptors that are visible on the depilated skin of mammals. These structures consist of a sharply circumscribed disk of thickened epithelium surmounting a group of Merkel cells that are innervated by type I sensory neurons. These characteristic cutaneous structures provide an ideal opportunity for investigating whether the localization of nerve growth factor (NGF) in the skin is related to sites of sensory axon termination. For these reasons, we have used immunocytochemistry to study the distribution of NGF and the low-affinity NGF receptor (p75NGFR) in the touch domes of adult rat skin. Intense NGF-like immunoreactivity was sharply restricted to keratinocytes (excluding the stratum corneum) of the thickened epidermis of touch domes. The epidermis immediately surrounding touch domes and the epidermis of the tylotrich hair follicle associated with touch domes were not stained by anti-NGF antiserum. Merkel cells of the basal epidermis of touch domes were immunonegative for NGF but were immunopositive for p75NGFR as were the type I nerve endings innervating these cells. Quantitative Northern blotting revealed that the level of NGF mRNA was substantially higher in keratinocytes isolated from the stratum granulosum and stratum spinosum than in keratinocytes isolated from the stratum germinativum. These findings indicate that NGF synthesis in mature skin has a highly restricted regional distribution that is primarily associated with the innervation of a specialized touch receptor.

Animals↗
PubMed1996

[Neuroendocrine primary cutaneous carcinoma. Therapeutic aspects in 13 patients].

INTRODUCTION: Since the description by Toker in 1972, neuroendocrine carcinoma or Merkel cell carcinoma, is a well identified clinical entity although the appropriate treatment is still debated. Wide surgical exeresis is indicated as first line treatment in all cases but the question concerning protocols for adjuvant radiotherapy or chemotherapy remains open. We analyzed retrospectively our series of 13 patients with neuroendocrine carcinoma looking for an association between radiotherapy and surgery. PATIENTS: There were 7 women and 6 men in our study population (age range 43-88 years). Two cancers of the rectum and one prostate cancer were associated. In 6 cases, the tumor was localized on the limbs, in 5 on the face and in 2 on the buttocks. Mean delay to diagnosis was 2.5 months. At diagnosis, only 1 patient had satellite nodes. The pathology examination evidenced intermediary cell type and architecture. Immunohistochemistry tests were positive for NSE, NF, KII and the ultrastructure confirmed the diagnosis. Nine patients were treated with surgical exeresis with wide 1 cm margins and was completed with radiotherapy of the tumoral bed at homogeneous doses of 45 to 60 Gy. Surgery alone was used in 4 patients. RESULTS: Mean follow-up was 27 months (5-98). Among the 13 operated patients, 11 have survived, 1 died due to the neoplasia and in 1 other from another cause. Local and regional recurrence rate after exercise alone was 50 p. 100 (2/4) with concomitant development of metastasis in both cases. When local or locoregional post-operative radiotherapy was given, local or regional recurrence rate was 33 p. 100 (2/6). DISCUSSION: Cutaneous neuroendocrine carcinoma or Merkel cell carcinoma is an uncommon skin tumor. It is difficult to determine the management protocol on the basis of data in the literature. Due to risk of locoregional recurrence, we currently propose post-operative radiotherapy of the tumor bed and drainage nodes in all patients.

Adult↗
PubMed2005

Cutaneous lesions: benign and malignant.

This article reviews the clinical characteristics, histology, biologic behavior, and recommended treatment for several benign and malignant lesions that may arise on the head and neck. Nevus sebaceus and congenital melanocytic nevus are two benign lesions that can present at a size of several centimeters. Surgical excision may be considered for cosmetic purposes and to reduce the small risk for the development of malignancy within each lesion. Basal and squamous cell carcinoma, lentigo maligna and lentigo maligna melanoma, dermatofibrosarcoma protuberans, and Merkel cell carcinoma are malignant lesions for which surgical excision is the recommended treatment. Local flap reconstruction may be used to address the surgical defects resulting from excision of these benign and malignant conditions.

Basal Cell Carcinoma↗
PubMed1998

[Management of hematologic systemic diseases and rare tumor entities with manifestations in the oromaxillofacial area].

Malignant lymphomas, hematological malignancies, sarcomas, occult head and neck primaries, Merkel cell carcinomas and malignant melanomas are among the tumors that are rarely seen in the head and neck region. Almost 20% of patients with acute leukemia initially present with symptoms of the oral cavity (ulcerations, gingival hypertrophy, etc.). If a malignant lymphoma is suspected, the lymph node should be removed in toto to ascertain diagnosis. Furthermore, in order to make sure that the immunohistological work-up or electron microscopic analysis is adequate, the pathologist should be informed prior to extirpation of the suspicious lymph node. The same diagnostic procedure is indicated for metastases from undifferentiated or small cell cancer of an unknown primary. Metastatic squamous cell or undifferentiated carcinoma to a solitary cervical lymph node from an unknown primary can be cured by multimodal therapy (extirpation, radical neck dissection and adjuvant radiation) in 30% of the cases. Following polychemotherapy, long-term survival may also be achieved in disseminated stages of undifferentiated carcinoma or poorly differentiated adenocarcinoma in an occult primary. When osteosarcoma of the jaw is suspected, core biopsy has to be planned carefully: in order to prevent tumor seeding, the needle track has to be excised during definitive surgery. Most authors propose (neo-)adjuvant chemotherapy (or chemoradiation) for head and neck osteosarcoma, especially when additional risk factors, i.e. a large primary or poorly differentiated sarcoma, are present. Patients with positive margins should receive adjuvant radiotherapy in soft tissue sarcoma. Local control of angiosarcoma is possible exclusively by radiation. Adjuvant radiation is also indicated in Merkel cell carcinoma. Because this tumor spreads in a "cascade" fashion, elective node dissection may also provide a chance for cure. Excision with wide margins is the principal therapeutic step in malignant melanoma. Due to the anatomic localization, adequate resection may not be possible in mucosal melanoma of the head and neck. When regional lymph nodes are involved, radical lymph node dissection and adjuvant radiation have to be added to the therapeutic concept. There is an emerging role for adjuvant interferon alpha in intermediate and high-risk melanoma.

Combined Modality Therapy↗
PubMed2003

CD56 expression of neuroendocrine neoplasms on immunophenotyping by flow cytometry: a novel diagnostic approach to fine-needle aspiration biopsy.

BACKGROUND: CD56 antigen or NCAM (neural cell adhesion molecule) has an established role in the diagnosis of non-Hodgkin lymphoma (NHL)-natural killer cell type and other hematologic malignancies. Therefore, it is included routinely in the panel of antibodies for flow cytometric (FC) analysis of suspected lymphomatous tissue specimens obtained from fine-needle aspiration biopsy (FNAB). The authors evaluated the role of CD56 expression on FC of neuroendocrine (NE) tumors. An initial diagnosis of NHL was suspected based on an on-site FNAB evaluation. METHODS: Ten FNABs were identified from the cytopathology files at The Johns Hopkins Hospital, Baltimore, MD (2000-2001). Flow cytometric analysis was negative for NHL but revealed a CD56-positive nonlymphoid cell population. An FNAB evaluation was performed on air-dried Diff-Quik-stained smears and FC analysis used a fixed panel of 12 antibodies (B-cell markers, T-cell markers, CD33, CD56, and CD71). Immunoperoxidase staining (IPOX) was performed on the cell block sections from four of the tissue specimens using epithelial and NE markers, CD56, desmin, and O13 antibodies. Sites of FNAB included the lung (five cases), liver (one case), lymph node (three cases), and peritoneum (one case). Only one patient had a history of cancer at the time of FNAB. RESULTS: All cytologic diagnoses were confirmed by histopathologic follow-up on resection or biopsy or both. Diagnoses included small cell carcinoma (eight cases), Merkel cell carcinoma (one case), and primitive neuroectodermal tumor/Ewing sarcoma (one case). All tissue specimens that underwent IPOX stained strongly with NE markers, with one tissue section staining only with O13. CONCLUSIONS: CD56 expression by FC in the presence of negative immunostaining with lymphoid markers represented a unique yet highly specific method for the diagnosis of NE tumors by FNAB. This procedure eliminated the need for further IPOX studies on the already limited cytologic sample and provided a timely and accurate diagnosis.

Adult↗
PubMed1989

Extensive changes in cytokeratin expression patterns in pathologically affected human gingiva.

The stratified squamous epithelium of the oral gingiva and the hard palate is characterized by a tissue architecture and a cytoskeletal composition similar to, although not identical with, that of the epidermis and fundamentally different from that of the adjacent non-masticatory oral mucosa. Using immunocytochemistry with antibodies specific for individual cytokeratins, in situ hybridization and Northern blots of RNA with riboprobes specific for individual cytokeratin mRNAs, and gel electrophoresis of cytoskeletal proteins of microdissected biopsy tissue samples, we show changes in the pattern of expression of cytokeratins and their corresponding mRNAs in pathologically altered oral gingiva. Besides a frequently, although not consistently, observed increase in the number of cells producing cytokeratins 4 and 13 (which are normally found as abundant components in the sulcular epithelium and the alveolar mucosa but not in the oral gingiva) and a reduction in the number of cells producing cytokeratins 1, 10 and 11, the most extensive change was noted for cytokeratin 19, a frequent cytokeratin in diverse one-layered and complex epithelia. While in normal oral gingiva cytokeratin 19 is restricted to certain, sparsely scattered cells of --or near--the basal cell layer, probably neuroendocrine (Merkel) cells, in altered tissue of inflamed samples it can appear in larger regions of the basal cell layer(s) and, in apparently more advanced stages, also in a variable number of suprabasal cells. Specifically, our in situ hybridization experiments show that this altered suprabasal cytokeratin 19 expression is more extended at the mRNA than at the protein level, indicating that cytokeratin 19 mRNA synthesis may be a relatively early event during the alteration. These changes in cytokeratin expression under an external pathological influence are discussed in relation to other factors known to contribute to the expression of certain cytokeratins and with respect to changes occurring during dysplasia and malignant transformation of oral epithelia.

Blotting, Northern↗
PubMed2006

Immunohistochemical localization of histamine H3 receptors in rodent skin, dorsal root ganglia, superior cervical ganglia, and spinal cord: potential antinociceptive targets.

Activation of histamine H3 receptors (H3Rs) reduces inflammation and nociception, but the existence of H3Rs on peripheral innervation has never been demonstrated. Here we use antibodies to locate H3Rs in whisker pads, hairy and glabrous hind paw skin, dorsal root ganglia (DRGs), and spinal cords of rats, wild type mice, and H3R knockout (H3KO) mice. Although H3Rs have been hypothesized to be on C and sympathetic fibers, H3R-like immunoreactivity (H3R-LI) was only detected on presumptive periarterial A delta fibers and on A beta fibers that terminated in Meissner's corpuscles and as lanceolate endings around hair follicles. The H3R-positive periarterial fibers were thin-caliber and coexpressed immunoreactivity for calcitonin gene-related peptide (CGRP), substance P, acid sensing ion channel 3, and 200 kDa neurofilament protein (NF). H3R-LI was also detected on epidermal keratinocytes and Merkel cells, but not on Merkel endings, C fibers, any other A delta fibers, or sympathetic fibers. In DRGs, H3R-LI was preponderantly on medium to large neurons coexpressing NF-LI and mostly CGRP-LI. In dorsal horn, CGRP-positive fibers with and without H3R-LI ramified extensively in lamina II; many of the former formed a plexus in lamina V. Low levels of H3R-LI were also present on A beta fibers penetrating superficial and into deeper laminae. The distribution of H3R-LI was similar in rats and wild type mice, but was eliminated or strongly reduced in A delta fibers and A beta fibers, respectively, in H3KO mice. Taken with recently published behavioral results, the present findings suggest that periarterial, peptidergic, H3R-containing A delta fibers may be sources of high threshold mechanical nociception.

Animals↗
PubMed1994

Visualization of PGP 9.5 immunoreactive nerve terminals in the mouse snout epidermis.

Intraepidermal free nerve endings were investigated in the mouse snout skin by means of an immunohistochemical procedure using a rabbit antiserum against protein gene product 9.5 (PGP 9.5). Immunoperoxidase reactivity was detected in different subtypes of intraepidermal nerves and cells. The great majority of axons observed in the stratified epithelium were varicose; a small percentage was either smooth (non-varicose) or irregularly shaped. Intraepidermal nerves ended at different levels within the epidermis, often with a terminal knob-like swelling. Various patterns of intraepidermal innervation could be distinguished. Most fibres entering the epidermis originated from large bundles running a horizontal course below the dermo-epidermal junction. Such fibres ascended vertically through the stratified epithelium in a "candelabrum-like" fashion, without emitting collaterals. Other fibres branched profusely and ended in complex intraepidermal neural networks. Less frequently, intraepidermal fibres terminated with large irregularly shaped expansions of different morphologies. Some of these were the intraepidermal continuations of axons within Meissner's corpuscles. Some fibres appeared to come into contact with PGP 9.5-immunoreactive cells (which closely resembled Merkel cells) located in the stratum basale. Rare suprabasal dendritic cells (Langerhans cells?) also became visible.

Animals↗
PubMed2004

Ets-1 immunohistochemical expression in non-melanoma skin carcinoma.

BACKGROUND: Ets-1 oncoprotein is a transcription factor known to regulate the expression of numerous genes important in extracellular matrix remodeling and angiogenesis. Up-regulation of Ets-1 has been shown to be important in a variety of human malignancies and to correlate with prognosis. To our knowledge, this oncoprotein has not been examined in non-melanoma skin carcinomas. DESIGN: A series of 26 primary cutaneous skin lesions with patient records were independently examined for diagnosis confirmation and immunohistochemical expression by two dermatopathologists. The immunohistochemical expression for Ets-1 (Novocastra, Newcastle Upon Tyne, England, UK) was scored by an average of the mean labeling intensity (MLI), where no nuclear staining = 0, weak nuclear staining = 1, moderate nuclear staining = 2, and strong nuclear staining = 3. RESULTS: All basal cell carcinoma (BCC) and Merkel cell carcinoma (MCC) cases exhibited negative nuclear staining, for an average MLI of 0. Keratoacanthomas, squamous cell carcinoma in situ (SIS), and well-differentiated squamous cell carcinomas (SCCs) exhibited negative to weak nuclear staining, for an average MLI of 0.4 +/- 0.3. Moderately differentiated SCCs exhibited moderate nuclear staining, for an average MLI of 1.8 +/- 0.6. Poorly differentiated SCCs and metastatic SCCs exhibited very strong nuclear staining, with an average MLI of 2.8 +/- 0.2. CONCLUSIONS: Ets-1 is not expressed in cutaneous BCC or MCC and is weakly expressed in SIS and forms of well-differentiated SCC. Although the intensity of Ets-1 immunostaining distinguished between well-differentiated and poorly differentiated SCC (p < 0.0001), it failed to discriminate between in situ and well-differentiated SCCs. The preliminary data suggests Ets-1 may be important in the pathogenesis of invasive SCC.

Biomarkers, Tumor↗
PubMed2003

Somatostatin receptor scintigraphy versus chromogranin A assay in the management of patients with neuroendocrine tumors of different types: clinical role.

BACKGROUND: Current diagnosis and staging of neuroendocrine tumors (NETs) are significantly improved by the introduction of the chromogranin A (CgA) assay in plasma or serum as a tumor marker, and by the use of somatostatin receptor scintigraphy (SRS) for tumor localization. However, the clinical role of CgA assay compared with SRS in the management of NETs has not been well elucidated. PATIENTS AND METHODS: Sixty-three consecutive patients with a histological diagnosis of NET underwent plasma CgA assay and SRS for tumor staging (23 cases), evaluation of tumor response (18 cases) and evaluation of tumor recurrence on follow-up (22 cases). Twenty-one patients had well-differentiated neuroendocrine tumors (WDNETs: 18 gastroenteropancreatic tumors and three lung NETs); 22 patients had well-differentiated neuroendocrine carcinomas (WDNECs: 17 gastroenteropancreatic carcinomas, two lung neuroendocrine carcinomas and three neuroendocrine carcinomas of unknown origin) and 20 patients had poorly differentiated neuroendocrine carcinomas (PDNECs: 14 extra-pulmonary small-cell carcinomas and six Merkel cell carcinomas). Almost all (58 of 63) NETs were non-functioning. The quantitative determination of CgA was performed in plasma using an enzyme immunoassay with a cut-off value fixed at 34 U/l. Scintigraphies with indium 111-DTPA-octreotide ((111)In-pentetreotide) included whole-body images and single photon emission computed tomography (SPECT) scans of the chest and abdomen. RESULTS: SRS results were compared with CgA findings and final clinical data. The overall sensitivity of SRS and CgA, based on the final clinical data, was 77% and 55%, respectively, whereas the specificity of both SRS and CgA was 94%. Concerning tumor type, SRS accuracy was 95% for WDNETs, 86% for WDNECs and 60% for PDNECs; CgA accuracy was 76% for WDNETs, 68% for WDNECs and 50% for PDNECs. With regard to disease extent, SRS sensitivity was 100% for limited disease and 72% for advanced disease; CgA sensitivity was 43% for limited disease and 57% for advanced disease. CONCLUSIONS: In our NET series, SRS proved to be more sensitive than CgA, with equivalent specificity. Tumor differentiation influences the sensitivity of SRS and CgA analysis. In addition, the plasma CgA level is related to tumor secretory activity. Nevertheless both SRS and CgA should be considered useful tools in the diagnostic work-up of NET patients.

Adolescent↗
PubMed1993

Cutaneous neuroblastoma. Peripheral neuroblastoma.

UNLABELLED: Cutaneous neuroblastoma (CN) is a rare tumor in adults. Histologically CN can be confused with other small, round cell tumors, especially with Merkel cell tumor. This is the second case that we have encountered in a 6-year period. A 46-year-old man with severe adult respiratory distress syndrome had a 2.5 x 2.0 x 2.0-cm, rapidly growing, fleshy nodule over his nose. The clinical impression was pyogenic granuloma (PG) or keratoacanthoma (KA). Histologically, the tumor showed undifferentiated cells with frequent Homer Wright rosettes and mitoses. Conventional special stains and a broad panel of immunohistochemical markers were applied that were positive only for neuron-specific enolase. Ultrastructurally the cells contained dense-core granules and immature desmosomes. The diagnosis of CN was made and an extensive radiologic and laboratory workup was initiated, but the results were negative for another primary tumor. The patient subsequently died and a thorough postmortem examination revealed multiple visceral metastatic lesions but no primary tumors in the adrenal glands, the sympathetic chain, or the central nervous system. CONCLUSIONS: (a) CN does occur in adults and can mimic other fast-growing tumors of the skin, for example, PG or KA; (b) the diagnosis of CN requires the combined use of immunohistochemistry and electron microscopy; and (c) the dermatologist should be aware of this rare, but important, tumor because its primary cutaneous manifestation may enable early recognition.

Humans↗