Felip Vilardell

Importance of assessing CK19 immunostaining in core biopsies in patients subjected to sentinel node study by OSNA

Analysis of sentinel lymph node (SLN) by means of One-Step Nucleic Acid Amplification (OSNA) is being used increasingly as a very sensitive and quick method for intraoperative axillary staging in patients with breast cancer. This molecular diagnostic assay detects the expression level of cytokeratin 19 (CK19), a luminal epithelial cell marker broadly expressed in most breast carcinomas and not normally found in lymph nodes. Almost all breast cancers express this cytoskeleton protein, but some breast tumors have been found to lose the expression of CK19. CK19 immunostaining in core biopsies has been recommended in selecting patients eligible for OSNA analysis because SLNs with metastatic involvement by CK19-negative breast cancers may result in a false negative result by OSNA. However, the real frequency of CK19-negative breast cancer has to be elucidated. In this study, we have assessed the frequency and molecular profile of CK19-negative breast carcinomas in three series of cases. The first is a prospective series of 197 breast carcinomas, 111 of which were subjected to SLN evaluation by OSNA. The second is a retrospective series of 41 triple-negative (TN) breast carcinomas, and the third is a retrospective series of 68 breast cancer patients (matched core biopsies and metastatic lymph nodes) that had been evaluated by conventional procedures before the OSNA methodology was adopted in our institution. Our results not only demonstrate that lack of expression of CK19 is infrequent in breast cancers but also that performing CK19 immunohistochemical staining is important on diagnostic core biopsies in taking the decision of using OSNA methodology in the evaluation of sentinel nodes in breast cancer patients.

Composite papillary intestinal-type adenocarcinoma/poorly differentiated neuroendocrine carcinoma of the ampulla of Vater

Mixed malignant ampullary tumours displaying adenomatous and neuroendocrine features are infrequent, with only nine reported cases, and almost all of them are composed of intestinal-type adenocarcinoma and well-differentiated neuroendocrine/carcinoid tumour.1 An 81-year-old man, with personal history of arterial hypertension, hypercholesterolaemia, type 2 diabetes mellitus and a previous appendectomy, presented with abdominal pain, fever and obstructive jaundice of 4-day duration. Physical examination was unremarkable but blood analysis showed an elevated alkaline phosphatase of 189 U/l (normal 40–130 U/l), and an elevated γ-glutamyltransferase of 255 U/l (normal 11–49 U/l). Aminotransferases were slightly elevated. Abdominal ultrasonography revealed dilated gallbladder and extrahepatic bile ducts. A cholangioresonance showed an exophytic mass in the ampulla of Vater, while an abdominal CT indicated a nodular lesion of 2 cm in the papillary region, suggesting ampullary adenocarcinoma. An endoscopic retrograde cholangiopancreatography and sphincterotomy were performed, and cytology and endoscopic biopsy were taken, revealing malignant cells, consistent with adenocarcinoma. Whipple resection was eventually performed. Grossly, the pancreaticoduodenectomy specimen showed an exophytic lesion of 2.7×1.6 cm obstructing the ampulla of Vater. A piece of this exophytic tumour was snap frozen in liquid nitrogen before fixation. H&E-stained sections of the entire lesion revealed an intestinal-type papillary tumour resembling a colonic villous adenoma, with cigar-shaped nuclei and some goblet cells, but with clear malignant features such as high nuclear atypia, high number of mitotic and apoptotic figures, and invasion in the lamina propria of the ampulla, with desmoplastic reaction. Some rests of peripheral adenoma could be seen. In some small areas this infiltrative intestinal-type …

Deletion of Pten in CD45-expressing cells leads to development of T-cell lymphoblastic lymphoma, but not myeloid malignancies

Since its discovery in the late 1990s, Pten has turned out to be one of the most important tumor suppressor genes. Pten loss results in increased activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, which is associated with increased proliferation, survival, and neoplastic growth. Here, we have addressed the effects of conditional deletion of Pten in hematopoietic cells by crossing Pten conditional knockout mice with a knock-in mouse expressing the Cre recombinase in the CD45 locus. CD45 is also known as leukocyte common antigen, and it is expressed in virtually all white cells and in hematopoietic stem cells. Using a reporter mouse, we demonstrate that CD45:Cre mouse displays recombinase activity in both myeloid and lymphoid cells. However, deletion of Pten in CD45-expressing cells induces development of T-cell acute lymphoblastic leukemia and lymphoma, but not other hematologic malignancies.

Topical Interferon Alpha-2b for Diffuse Conjunctival Primary Acquired Melanosis with Atypia

An 80-year-old Caucasian male presented to our office with diffuse primary acquired melanosis (PAM) in the conjunctiva of the right eye (Figure 1; photomontage superior-left). The conjunctival pigmentation had increased progressively during the last 2 years. PAM affected only the bulbar conjunctiva in the four quadrants. The lid conjunctiva was not affected and there were no elevated parts within the lesion. His medical history included cognitive impairment due to dementia and general malaise due to known osseous metastasis, secondary to prostate carcinoma. There were no clinical criteria to differentiate whether this case of PAM was without or with atypia (melanoma in situ). In this case, due to the conjunctival extension, complete resection of the lesion could lead to mutilation of the ocular surface. Therefore, an incisional biopsy of the area (10 × 8 mm) of the superior lesion was performed. Histology confirmed the presence of atypical melanocytes in the basal layers of the epithelium confirming conjunctival PAM with severe atypia. The C-MIN score was >5, similar to a melanoma in situ (Figure 1, right). In this case, the entire lesion was not removed and the presence of atypical melanocytes was suspected in all four quadrants. Further biopsies can only confirm the diagnosis. While complete excision was possible, consequent scarring would have resulted in a compromised outcome. Complete surgical removal and covering with amniotic membrane may be a good technique in extensive corneo-conjunctival lesions. However, in this case most of the bulbar conjunctiva would have had to be removed, resulting in mutilating surgery, and therefore was not considered acceptable. Topical chemotherapy is not employed as a primary treatment in cases of PAM. However, it may be employed in extensive lesions. Topical interferon (IFN) alpha-2b has been used successfully for the treatment of ocular surface squamous neoplasia (OSSN). Topical IFN is well tolerated in the treatment of OSSN. Few reports have described its utility for the treatment of pigmented conjunctival lesions, including PAM and melanoma. After informed consent was obtained, topical treatment with eye drops containing 1 million IU/mL of IFN alpha-2b (4 times a day) was initiated. The lesion was monitored by photographic review every 2 weeks. Topical IFN was well tolerated. The resolution of pigmentation began after 6 weeks of treatment. The pigmentation decreased progressively, and after 12 weeks, the treatment regimen was stopped. The reason was because the pigmentation had diminished considerably and the patient’s family had difficulties with the administration of the eye drops. The duration of treatment was also based on the reported average duration of topical IFN administration in previous publications. The remaining pigmentation continued to diminish for almost a full year after the initiation of treatment (Figure 1; photomontage inferior-left). Histologic confirmation of the resolution was not performed because the patient declined due to the poor general condition of the patient. PAM is an acquired pigmentation that occurs gradually in middle age and may appear as localized, patchy, flat, multifocal, or diffuse pigmentation in the conjunctiva. Abnormal melanocytes near the basal layer of the epithelium are characteristic of PAM. The risk of atypical melanocytes transforming into a malignant melanoma is approximately 50%. Excision with double freeze–thaw cryotherapy is the elective treatment for PAM with atypia. In cases of diffuse disease, topical chemotherapy may be used instead of excision. Mitomycin C (0.02 or 0.04% over several cycles) is the most frequently used drug. However, topical

CK19 expression should be tested prior to OSNA analysis of sentinel lymph nodes in breast cancer

Dear Editor, The observations of Remoundos et al. [1] are quite interesting. Effectively, there is not a direct relationship between presence of mRNA and expression of protein. In the first case of breast cancer in which we found lack of CK19 expression, absence of CK19 mRNA was confirmed by Sysmex S.L. by means of a RT-PCR, which confirmed that truly CK19-negative tumours can be found among those with a luminal phenotype and not only among those with a triple-negative phenotype. After terminating the study, we found five more cases lacking CK19 expression. For various reasons, we did not confirm the mRNA status of these tumours, but the one-step nucleic acid amplification (OSNA) assay was not performed and sentinel lymph nodes (SLN) were studied by means of standard procedures. Even though the proportion of breast cancers lacking CK19 mRNA is most likely lower than that of immunohistochemically CK19-negative tumours, we think it may be hazardous to perform the OSNA assay in cases lacking expression of CK19. In our paper [2], we reported a case of a luminal-A breast carcinoma expressing CK19 in only very few cells, both in the primary tumour and in the matched SLN macrometastasis. This metastasis probably would have been detected by the OSNA analysis, not as macrometastasis but with a diagnosis of micrometastasis or even as isolated cells. Dr. Remoundos affirms that they found on OSNA analysis a micrometastasis in a SLN from a patient with a breast cancer lacking CK19 expression. How do they know that that metastasis was a micrometastasis and not a macrometastasis?

Immunocryosurgery as monotherapy for lentigo maligna or combined with surgical excision for lentigo maligna melanoma

The incidence of lentigo maligna (LM), in situ (LM) or invasive (lentigo maligna melanoma, LMM), has increased during the last decades. Due to functional or cosmetic outcomes, optimal treatment with surgical excision may not be appropriate in some cases. We tried less invasive therapy, immunocryosurgery, as a single treatment for LM or combined with surgery for LMM, with better aesthetic results. Three patients with LM or LMM not amenable to complete surgical excision were selected. LMM patients underwent limited surgical resection of the invasive area. Subsequently, a combined treatment with topical imiquimod and cryosurgery was performed. The LM patient received immunocryosurgery directly. All of them were free of local and systemic disease at 48, 42 and 41 months after discontinuation of therapy. We consider that immunocryosurgery is an alternative option for LM or even for LMM (after removal of the invasive tissue with narrow margins) in poor surgical candidates, with good therapeutic, functional and cosmetic results.

Vulvar Basal Cell Carcinoma: Four Case Reports With Immunohistochemical Study

Basal cell carcinomas (BCC) are the most frequent tumours in humans and normally appear in photoexposed areas of the skin. It is widely accepted that BCCs originate at follicular stem cells and consequently are very rare in nonhairy areas. Here, we report 4 cases of vulvar BCC, 3 of which were located in a vulvar semimucous area, a nonphotoexposed area, and a nonhairy area. We have determined the CK7 and CK19 profile of all cases; both are markers of simple epithelium with glandular differentiation. Interestingly, all cases were positively stained for CK7 and CK19. Considering that the vulvar region is rich in sebaceous and apocrine units, we hypothesise a glandular origin of BCCs situated in the vulvar region.

Cytokeratin Profile of Basal Cell Carcinomas According to the Degree of Sun Exposure and to the Anatomical Localization

Abstract: Basal cell carcinoma (BCC) seems to originate from ultraviolet light-induced mutations involving the bulge or the outer sheath of the hair follicle cells. However, the etiopathogenic mechanisms involved in the development of these tumors in nonphotoexposed and in hairless areas remain unclear. The cytokeratin (CK) profile (including CK5/6, CK7, CK14, CK15, CK17, and CK19) from a series of different BCC subtypes developing in sun-exposed and non–sun-exposed areas, including hairless regions, was evaluated. The authors have observed that CK7 expression in BCC is associated with the anatomical localization of the tumor and its sun-exposition, but not with other factors such as histological subtype. The expression of this CK is higher in BCCs located in non–sun-exposed and nonhairy areas, such as the vulvar semimucosa and the nipple. Because CK7 is a marker of simple glandular epithelia, the authors suggest a glandular origin for BCCs located in hairless and nonphotoexposed areas.