Perineural Infiltration: A Comprehensive Review of Diagnostic, Prognostic, and Therapeutic Implications

ABSTRACT

Perineural infiltration refers to a neoplastic cell involvement in, around, and through the nerves. It is considered as one of the neoplastic dissemination pathways. Thus, its identification is crucial to establish the prognosis of some malignant skin neoplasms, such as squamous cell carcinoma, and explains the locally aggressive behavior of cutaneous neoplasms, such as microcystic adnexal carcinoma. We have conducted a review of malignant and benign skin tumors in which perineural infiltration has been described, and we also discuss some histopathological findings that may simulate perineural infiltration.

Clinical, histopathologic, immunohistochemical, and electron microscopic findings in cutaneous monkeypox: A multicenter retrospective case series in Spain

BACKGROUND

The worldwide outbreak of monkeypox has evidenced the usefulness of the dermatologic manifestations for its diagnosis.

OBJECTIVE

To describe the histopathologic and immunohistochemical findings of monkeypox cutaneous lesions.

METHODS

This is a retrospective histopathologic and immunohistochemical study of 20 patients with positive Monkeypox virus DNA polymerase chain reaction and immunohistochemical positivity for Vaccinia virus in cutaneous lesions. Four cases were also examined by electron microscopy.

RESULTS

The most characteristic histopathologic findings consisted of full-thickness epidermal necrosis with hyperplasia and keratinocytic ballooning at the edges. In some cases, the outer root sheath of the hair follicle and the sebaceous gland epithelium were affected. Intraepithelial cytoplasmic inclusion bodies and scattered multinucleated keratinocytes were occasionally found. Immunohistochemically, strong positivity with anti-Vaccinia virus antibody was seen in the cytoplasm of ballooned keratinocytes. Electron microscopy study demonstrated numerous viral particles of monkeypox in affected keratinocytes.

LIMITATIONS

Small sample size. Electron microscopic study was only performed in 4 cases.

CONCLUSION

Epidermal necrosis and keratinocytic ballooning are the most constant histopathologic findings. Immunohistochemical positivity for Vaccinia virus was mostly detected in the cytoplasm of the ballooned keratinocytes. These findings support the usefulness of histopathologic and immunohistochemical studies of cutaneous lesions for diagnosis of monkeypox.

Bowen Disease Within a Circumscribed Palmar Hypokeratosis

ABSTRACT

Circumscribed palmar or plantar hypokeratosis is a focal disorder of keratinization that consists of a reduction in the thickness of the corneal layer of the epidermis of palms or soles. Although it is considered a benign entity, the thinning of the stratum corneum facilitates ultraviolet damage in the affected skin, which may result in an increased risk of developing focal epidermal dysplasia. Other factors, such as immunosuppression in transplanted patients, may play a role as well. We present a case of circumscribed palmar or plantar hypokeratosis with features of Bowen disease limited to the hypokeratotic epidermis.

Immunophenotypic Differences in Tumor-Infiltrating Lymphocytes and Neovascularization Between Primary Cutaneous Melanoma With and Without Metastasis: An Immunohistochemical Study of 80 Cases

ABSTRACT

The prognostic implications of the immunophenotype of the tumor-infiltrating lymphocytes (TILs) in primary cutaneous melanoma are well known. In recent years, the study of this immunophenotype has also resulted in immunotherapeutic consequences. The aims of this study were to characterize the subpopulations of TILs in primary cutaneous melanoma, in cases with and without metastasis, as well as the neovascularization associated with the primary neoplasm, and its influence on the development of metastasis. To this end, the immunophenotype of TILs and the neovascularization of 80 patients with primary cutaneous melanoma (40 each with metastatic and non-metastatic melanoma) were analyzed by immunohistochemistry for CD3, CD4, CD8, FOXP3, PD-1, CD31, and D2-40 antibodies. We found that higher frequencies of TILs with brisk pattern, and CD4+, CD8+, and CD20+ cells in TILs, and a lower frequency of CD31+ vessels were histopathological features associated with better prognosis in primary cutaneous melanoma. Our results support the notion that the immunohistochemical study of TILs and neovascularization in primary cutaneous melanoma may be helpful tools for identifying patients at increased risk of metastasis development.

Frequent activating PIK3CA mutations in sporadic angiolipoma

BACKGROUND

Angiolipoma (AL) is considered as a lipoma variant that is characterized by the combination of mature adipocytes and capillary blood vessels diffusely distributed within the tumor. With the exception of recurrent PRKD2 mutations of uncertain pathogenetic significance, the genetic abnormalities of ALs are unknown, in the absence of any of the specific chromosomal aberrations described in other lipoma variants.

METHODS

Formalin-fixed and paraffin-embedded blocks of 13 conventional ALs and 5 cellular ALs from 17 individuals were retrieved and analyzed for mutations in exons 9 and 20 of PIK3CA by polymerase chain reaction and Sanger sequencing.

RESULTS

Activating PIK3CA mutations were identified in 14 tumors (78%). All PIK3CA-mutated samples carried the same exon 9 mutation, c.1634A>C (p.E545A). No mutation was detected in exon 20 of PIK3CA. No significant difference between PIK3CA-mutated and wild-type samples appeared to exist based on age, gender, and location of the tumor. All 5 cellular ALs carried the p.E545A PIK3CA mutation.

CONCLUSION

The high frequency of the p.E545A PIK3CA mutation in both conventional and cellular ALs suggests that activation of the PI3K/AKT pathway plays a key role in AL pathogenesis and reinforces the concept that cellular AL should be regarded as a variant of AL.

Combination of Congenital and Deep Penetrating Nevus by Acquisition of β-Catenin Activation

Deep penetrating nevus (DPN) is an intradermal, sometimes compound benign melanocytic lesion, which involves the reticular dermis, occasionally reaching the subcutis, which can raise concern for melanoma both clinically and histologically. Recently, it has been genetically defined by the combination of MAPK activating and β-catenin activating mutations. We sought to investigate genetic alterations in 2 cases of combined nevi of congenital melanocytic and DPN. Case 1 was a 16-year-old woman with a pigmented lesion on the trunk since birth, which was completely excised. Histopathological examination revealed a combined congenital nevus with a DPN. Comparative genomic hybridization showed no major genetic alterations, except for gain of 6q11.1 and point mutation of B-RAF V600E. Case 2 was a 62-year-old woman with a congenital pigmented lesion on the back. The lesion was diagnosed as a combined nevus of congenital and DPN. Comparative genomic hybridization showed no genetic alterations, and the NRAS Q61K was detected in both components. DPN is in most cases part of a combined nevus. Our cases showed strong and uniform nuclear expression of β-catenin and cyclin D1 in the DPN component suggesting the evolution of the congenital nevus to the DPN clone by acquiring β-catenin activating mutation.

Increased Marginal Stiffness Differentiates Infiltrative From Noninfiltrative Cutaneous Basal Cell Carcinomas in the Facial Area: A Prospective Study

OBJECTIVES

Basal cell carcinoma (BCC) is the most common dermatologic malignant skin cancer. Infiltrative histologic variants are more aggressive and require wider surgical margins or Mohs surgery, in contrast with noninfiltrative variants, which are commonly treated with standard surgical excision. Elastography has not been used to date to differentiate between the histologic variants of BCC. The purpose of this study was to differentiate infiltrative from noninfiltrative BCCs on elastography.

METHODS

A total of 31 facial BCCs were studied. Preoperatively, color Doppler ultrasound and strain elastographic examinations of the lesions were performed. The size, intralesional vascularization, and presence of hyperechoic dots were considered relevant B-mode and color Doppler variables. Strain ratios of the tumors were obtained with respect to adjacent healthy tissue. Increased marginal stiffness, which was considered hardness in greater than 50% of the tumor margin, was also blindly evaluated. Histologic confirmation and subtyping (infiltrative or noninfiltrative) were performed in all cases.

RESULTS

Infiltrative BCCs did not differ in the size, presence or absence of hyperechoic dots, or vascularization from noninfiltrative BCCs. Strain ratios were similar in both infiltrative and noninfiltrative BCCs (mean ± SD, 1.82 ± 0.879 versus 2.2 ± 1.11). However, infiltrative BCCs had statistically increased marginal stiffness in comparison with noninfiltrative BCCs (88.0% versus 18.8%). Increased marginal stiffness had sensitivity and specificity of 0.89 and 0.82 respectively, with a positive predictive value of 0.67 for infiltrative BCCs and a negative predictive value of 0.95 for noninfiltrative BCCs.

CONCLUSIONS

Histologic variants of BCC have different elastographic patterns. These differences may be of help in preoperative assessments of the BCC subtype and specific surgical planning, avoiding unnecessary skin biopsies.

Tissue-specific expression and post-transcriptional regulation of the ATPase inhibitory factor 1 (IF1) in human and mouse tissues

The ATPase inhibitory factor 1 (IF1) is an intrinsically disordered protein that regulates the activity of the mitochondrial ATP synthase. Phosphorylation of S39 in IF1 prevents it from binding to the enzyme and thus abolishes its inhibitory activity. Dysregulation of IF1 is linked to different human diseases, providing a relevant biomarker of cancer progression. However, the tissue content of IF1 relative to the abundance of the ATP synthase is unknown. In this study, we characterized the tissue-specific expression of IF1 in human and mouse tissues and quantitated the content of IF1 and of ATP synthase. We found relevant differences in IF1 expression between human and mouse tissues and found that in high-energy-demanding tissues, the molar content of IF1 exceeds that of the ATP synthase. In these tissues, a fraction of IF1 is bound to the enzyme, and the other fraction is phosphorylated and hence is unable to bind the enzyme. Post-transcriptional control accounts for most of the regulated expression of IF1, especially in mouse heart, where IF1 mRNA translation is repressed by the leucine-rich pentatricopeptide repeat containing protein. Overall, these findings enlighten the cellular biology of IF1 and pave the way to development of additional models that address its role in pathophysiology.-Esparza-Moltó, P. B., Nuevo-Tapioles, C., Chamorro, M., Nájera, L., Torresano, L., Santacatterina, F., Cuezva, J. M. Tissue-specific expression and post-transcriptional regulation of the ATPase inhibitory factor 1 (IF1) in human and mouse tissues.

Comparative study of adjuvants for allergen-specific immunotherapy in a murine model

AIM

To compare the immunological and clinical changes induced by allergen-specific immunotherapy (AIT) using different adjuvants.

MATERIALS & METHODS

Olea europaea pollen-sensitized mice were treated with olea plus aluminum hydroxide, calcium phosphate, monophosphoryl lipid A (MPL) or immunostimulatory sequences (ISS).

RESULTS

Aluminum hydroxide seems to drive initially to a Th2-type response. Bacteria-derived adjuvants (MPL and ISS) skew the immune response toward Th1 and Treg pathways. Specific-IgE production was lower after AIT with MPL and ISS. Moreover, IgG2a production significantly increased in ISS-treated mice. Bacteria-derived adjuvants also improved the Th1 cytokine response due to IFN-γ higher secretion. In addition, they improved bronchial hyper-reactivity and lung inflammation.

CONCLUSION

Bacteria-derived adjuvants may enhance the efficacy of AIT.

Neuropeptide Y expression in primary cutaneous melanoma

BACKGROUND

Neuropeptide Y (NPY) is involved in the carcinogenesis of different tumours, especially neural crest-derived tumours.

OBJECTIVE

The aim of our study is to investigate the expression of NPY on melanoma and its relation with prognostic histological parameters and survival.

METHODS

This is a retrospective observational study of two independent series, with a total of 79 primary melanomas, diagnosed in two independent University Hospitals in Spain, from January 2000 to December 2004.

RESULTS

We found a significant higher expression of NPY on superficial spreading melanoma and lentigo maligna (40%) (P = 0.030). Thinner tumours were associated with higher NPY expression (Clark level, P = 0.003; Breslow level, P = 0.012). Melanomas with low NPY expression were associated with intense cell proliferation (Ki-67, P = 0.034), high density of peritumoral mast cell infiltrates (P = 0.033) and low E-cadherin expression (P = 0.031). Melanomas with high NPY expression exhibited significant differences in terms of relapse time (median: 114 vs. 68 months, P = 0.008) and overall survival (114 vs. 74 months, P = 0.004).

CONCLUSION

High expression of NPY was associated with better prognostic histological parameters, low peritumoral mast cells density, presence of adhesion proteins and better outcome.

Psammomatoid ossifying fibromas: immunohistochemical analysis and differential diagnosis with psammomatous meningiomas of craniofacial bones

OBJECTIVE

To clarify the role of immunohistochemistry in the diagnosis of psammomatoid ossifying fibroma (PSOF), conventional cemento-ossifying fibroma (COF), and psammomatous meningioma (PM) of the craniofacial skeleton.

STUDY DESIGN

The histology and immunohistochemistry of 4 PSOFs, 6 COFs, and 7 PMs was studied. Antibodies included EMA, cytokeratins, smooth muscle actin (SMA), desmin, vimentin, CD34, CD10, S-100 protein, and glial fibrillary acidic protein (GFAP).

RESULTS

All PSOFs showed multiple round ossicles homogeneously distributed within a fibroblastic stroma. Psammomatous meningiomas had meningothelial features. All tumors, except 1 COF, were positive for EMA. All of them expressed vimentin, and none showed cytokeratins. Staining for SMA and S-100 protein was variable. CD10 was positive in all cases except 2 meningiomas. CD34 and GFAP stained only 1 case of meningioma each.

CONCLUSIONS

The diagnosis of PSOF should rest on histologic features. An incorrect diagnosis of meningioma based on the expression of EMA should be avoided.

Acute respiratory distress syndrome: underrecognition by clinicians and diagnostic accuracy of three clinical definitions

OBJECTIVE

To determine and compare the diagnostic accuracy of three clinical definitions of acute respiratory distress syndrome (ARDS): (1) the American-European consensus conference definition; (2) the lung injury score; and (3) a recently developed Delphi definition. A second objective was to determine the accuracy of clinical diagnoses of ARDS made in daily practice.

DESIGN

Independent comparison of autopsy findings with the daily status of clinical definitions, constructed with data abstracted retrospectively from medical records.

SETTING

Tertiary intensive care unit.

PATIENTS

One hundred thirty-eight patients from the period 1995 through 2001 who were autopsied after being mechanically ventilated.

INTERVENTIONS

Clinical ARDS diagnoses were determined daily without knowledge of autopsy results. Charts were reviewed for any mention of ARDS in the clinical notes. Autopsies were reviewed independently by two pathologists for the presence of diffuse alveolar damage. The sensitivity and specificity of the definitions were determined with use of diffuse alveolar damage at autopsy as the reference standard.

MEASUREMENTS AND MAIN RESULTS

Diffuse alveolar damage at autopsy was documented in 42 of 138 cases (30.4%). Only 20 of these 42 patients (47.6%) had any mention of ARDS in their chart. Sensitivities and specificities (95% confidence intervals) were as follows: American-European definition, 0.83 (0.72-0.95), 0.51 (0.41-0.61); lung injury score, 0.74 (0.61-0.87), 0.77 (0.69-0.86); and Delphi definition, 0.69 (0.55-0.83), 0.82 (0.75-0.90). Specificity was significantly higher for both the lung injury score and Delphi definition than for the American-European definition (p < .001 for both), whereas comparisons of sensitivity, which was higher for the American-European definition, were not significantly different (p = .34 and p = .07, respectively).

CONCLUSIONS

Acute respiratory distress syndrome appears underrecognized by clinicians in patients who die with this syndrome. In this population, the specificities of existing clinical definitions vary considerably, which may be problematic for clinical trials.

Comparison of clinical criteria for the acute respiratory distress syndrome with autopsy findings

BACKGROUND

The American-European Consensus Conference definition for the acute respiratory distress syndrome (ARDS) has never been validated.

OBJECTIVE

To compare clinical criteria for ARDS with autopsy findings.

DESIGN

Independent comparison of autopsy findings with clinical characteristics retrospectively abstracted from medical records.

SETTING

Tertiary medical-surgical intensive care unit.

PARTICIPANTS

382 patients who underwent clinical autopsy.

MEASUREMENTS

Sensitivity, specificity, and likelihood ratios for clinical criteria were calculated in 3 cohorts by using diffuse alveolar damage at autopsy as the reference standard. The 3 cohorts were 1) all patients, 2) patients with any risk factor for ARDS, and 3) patients who were separated according to their pulmonary or extrapulmonary risk factors.

RESULTS

127 patients (33%) met the clinical criteria, and 112 (29%) had diffuse alveolar damage. In all patients, the sensitivity of the clinical definition was 75% (95% CI, 66% to 82%) and the specificity was 84% (CI, 79% to 88%). In 284 patients with risk factors, the sensitivity was 76% (CI, 67% to 83%) and the specificity was 75% (CI, 68% to 81%). Compared with patients with pulmonary risk factors, patients with extrapulmonary risk factors had significantly higher sensitivity (61% vs. 85%; P = 0.009) and the specificity did not statistically significantly differ (69% vs. 78%; P > 0.2).

LIMITATIONS

Only patients who died and underwent autopsy could be included in this study, so these results may not apply to less severe cases of ARDS.

CONCLUSIONS

In a series of autopsy patients, the accuracy of the American-European Consensus Conference definition of ARDS was only moderate. The definition was more accurate for patients with extrapulmonary risk factors than for patients with pulmonary risk factors.

Incidence of chromosome numerical changes in multiple myeloma: fluorescence in situ hybridization analysis using 15 chromosome-specific probes

The presence of complex karotypes with frequent numerical and structural abnormalities has been reported in 20 to 50% of multiple myeloma (MM) patients. This variability is mainly due to the difficulty of conventional cytogenetics to obtain tumor metaphases representative of all possible neoplastic clones in MM. To gain insight into the real incidence of numerical chromosome changes in MM we have studied by fluorescence in situ hybridization technique 15 different human chromosomes, 1, 3, 6, 7, 8, 9, 10, 11, 12, 13, 15, 17, 18, X, and Y, in a series of 52 MM patients. In all cases, the DNA index assessed by a propidium iodide/CD38 double-staining technique with flow cytometry was simultaneously investigated for correlation, with fluorescence in situ hybridization results. Additional aims of this study were 1) to analyze whether the abnormalities detected were common to all plasma cells or were present in only a subpopulation of tumor cells, 2) to explore changes caused by disease progression, and 3) to establish possible associations among the altered chromosomes. Although the overall incidence of numerical abnormalities was 67%, this frequency increased to 80% in the 41 cases in which 7 or more chromosomes were analyzed. Trisomies were significantly more common than monosomies (84% versus 16%). Chromosomes 9 and 15 were the most frequently altered (52% and 48% of cases, respectively), with all of their abnormalities corresponding to trisomies. The most frequent losses involved chromosomes 13 (26%) and X in females (32%). Other common numerical changes corresponded to chromosomes 1 (39%), 11 (37%), 6 (32%), 3 (31%), 18 (29%), 7 (28%), and 17 (22%). By contrast, chromosomes 8(13%), 10(8%), and 12(3%) were rarely altered. DNA aneuploidy by flow cytometry was detected in 67% of patients, and a high degree of correlation was observed between the DNA index obtained by flow cytometry and the chromosome index derived from fluorescence in situ hybridization studies, calculated according to two mathematical formulas (coefficient of correlation of 0.82 and 0.91 when at least 7 or 12 chromosomes were considered, respectively). The frequency of numeric chromosome aberrations was higher in those patients with progressive disease and, interestingly, trisomy of chromosome 8 was exclusively detected in this latter group of patients. Our study shows that, with the exception of chromosome 8, a possible marker of clonal evolution, the numeric chromosome changes are present in nearly all malignant plasma cells (r > 0.84). Finally, frequent associations between chromosomal aberrations were observed (ie, chromosomes 6, 7, 9, and 17; 7 and 15; and 11 and 17). By excluding them, it was found that two triple combinations of chromosome-specific probes, chromosomes 1 and 9 together with either chromosome 13 or 15, could be a useful marker for detection of residual disease, as it permits the identification of most MM patients displaying numerical changes.