Humpath.com - Human pathology

fibroepithelioma

2013-05-22T15:57:55Z

Fibroepithelioma presents as a soft nodular lesion resembling a fibroma or papilloma, often on the lower part of the back.

It is composed of thin anastomosing strands of basaloid cells set in a prominent loose stroma.

The stroma has no elastic tissue.

Merkel cells are quite prominent.

It has been suggested, and subsequently disputed, that this variant derives its histological pattern from the spread of basal cell carcinoma down eccrine ducts, eventually replacing them with solid strands of tumor.

A rare cystic variant of fibroepithelioma has been reported.

basosquamous carcinoma

2013-05-22T15:56:58Z

Basosquamous carcinoma is a controversial entity which can be defined as a basal cell carcinoma differentiating into a squamous cell carcinoma.

It is composed of three types of cell:
basaloid cells, which are slightly larger, paler and more rounded than the cells of a solid basal cell carcinoma;
squamoid cells with copious eosinophilic cytoplasm;
an intermediate cell which resembles that seen in metatypical tumors.

Accordingly, the basosquamous carcinoma is sometimes confused with metatypical and keratotic basal cell carcinomas.

It is an aggressive lesion with metastatic potential.

This tumor shows some areas of Ber EP4 positivity, in contrast to squamous cell carcinoma which is always negative.

metatypical basal cell carcinoma

2013-05-22T15:55:54Z

Metatypical type

Although the term 'metatypical' is sometimes applied to tumors with mixed basaloid and squamous features, it should be reserved for the rare basal cell carcinoma composed of nests and strands of cells maturing into larger and paler cells.

Peripheral palisading is often lost.

The cells express much less keratin 17 and keratin 8 than do the cells in the more usual types of basal cell carcinoma.

Peripheral palisading is less obvious than usual, and the stroma is often prominent.

This variant is regarded by some as having metastatic potential.

infundibulocystic basal cell carcinoma

2013-05-22T15:55:04Z

Infundibulocystic type
The uncommon infundibulocystic variant, found most often on the face, is often confused with the keratotic type.
It is small, well circumscribed, and composed of nests of cells arranged in an anastomosing fashion with little stroma.
There are numerous small infundibular cyst‑like structures containing keratinous material and sometimes melanin.
The stroma may contain amyloid and/or melanin.
Multiple lesions are sometimes (...)

- Skin

sclerosing basal cell carcinoma

2013-05-22T15:53:51Z

Sclerosing type

The sclerosing category includes lesions which have also been referred to as fibrosing, scirrhous, desmoplastic and morpheic.

The uncommon 'field fire' type with central fibrosis resulting from regression should not be included in this category. Up to 5% of all basal cell carcinomas are of the sclerosing type.

The tumor presents as an indurated, pale plaque with a slightly shiny surface and clinically indistinct margins. There are narrow elongated strands and small islands of tumor cells embedded in a dense fibrous stroma.

If the stroma has dense, eosinophilic areas resembling a keloid, then the term 'morpheic' has traditionally been used, although at other times this term has been used interchangeably with 'sclerosing'.

The term 'keloidal' has been applied to basal cell carcinomas with thick sclerotic keloidal collagen bundles in the stroma.

A selectively enhanced procollagen gene expression has been found in the sclerosing variant. Also, large defects have been found in the basal lamina that surrounds the tumor nests. Smooth muscle (x‑actin and myosin) are often present in the stroma.

adenoid basal cell carcinoma

2013-05-22T15:52:47Z

Adenoid type
The adenoid variant consists of thin strands of basaloid cells in a reticulate pattern. Stromal mucin is often quite prominent. The adenoid type is quite uncommon in a pure form. It may occur in association with the solid type.

- Skin

pigmented basal cell carcinoma

2013-05-22T15:52:18Z

Pigmented type

Melanin pigment is usually formed in solid, micronodular, multifocal superficial or follicular variants.

Functional melanocytes are scattered through the tumor islands and there are numerous melanophages in the stroma. There are few melanosomes within the tumor cells.

Melanosome complexes form in tumor cells as a consequence of repeated cycles of phagocytosis of melanosome‑containing tumor cells that have undergone apoptosis.

Basal cell carcinomas of the usual type are also populated by some melanocytes.

Other pigmented phenomena in basal cell carcinomas are the colonization one by a melanoma in situ, the metastasis of a melanoma to one, and the presence of a combined melanoma and basal cell carcinoma.

cystic basal cell carcinoma

2013-05-22T15:51:26Z

Cystic type
One or more cystic spaces are present toward the center of some or all of the tumor islands. This results from the degeneration of tumor cells centrally, and it may be associated with increased mucin between the tumor cells adjacent to the cyst.

- Skin

micronodular basal cell carcinoma

2013-05-22T15:50:40Z

Micronodular type
The micronodular variant resembles the solid type, but the nests are much smaller and the peripheral palisading is not always as well developed. The micronodular type has a much greater propensity for local recurrence than the solid type. Sometimes it infiltrates quite widely through the dermis and extends into the subcutis. The micronodular type is often included incorrectly with the infiltrating or solid (...)

- Skin

keratotic basal cell carcinoma

2013-05-22T15:42:55Z

Keratotic type
Keratotic type
The keratotic variant is similar to the solid type, with nests and islands of basaloid cells with peripheral palisading.
It differs in the presence of squamous differentiation and keratinization in the centers of the islands.
There is usually very little stroma, and no lobular arrangement or follicular differentiation.

- Skin

infiltrative basal cell carcinoma

2013-05-22T15:33:12Z

Infiltrating type

This type, consisting of 10% of all BCC, includes non-sclerosing and sclerosing histological variants with an infiltrating rather than expansible growth pattern, where long, thin strands of tumour cells penetrate deeply among the collagen fascicles.

The superficial layers of the tumour often have a solid growth pattern and the infiltrative type is present in the lower or peripheral layers of the tumour.

If excision is not complete, this tumour can be included in the nodular type and the
infiltrative type is detected only during re-excision.

The sclerosing (morpheic, fibrosing, cicatricial or desmoplastic) variant of infiltrative BCC is characteristic of an increased number of fibroblasts and the presence of fibrotic desmoplastic stroma, which gives the tumour a characteristic clinical picture of a morphea or keloid scar.

Non‑sclerosing variant

This non‑sclerosing variant has an infiltrative rather than an expansile pattern of growth. It accounts for approximately 5% of all tumors, although this figure is higher in some patient groups.

The histological features are distinctive, with elongated strands of basaloid cells, cells thick, infiltrating between collagen bundles. Sometimes, even narrower strands are present, with spiking projections. There may be a slight increase in fibroblasts, but there is no significant fibrosis. Often there is a solid pattern superficially with the infiltrating nests at the periphery or base of the lesion. Sometimes a focal infiltrative pattern is seen in the re‑excision specimen of a biopsy proven solid (nodular) basal cell carcinoma.

These changes are limited to the region of the biopsy scar and appear to represent a scar induced phenomenon without any sinister connotations.

Like the sclerosing variant, it has a clinically indistinct border, but it differs from that variant in its opaque, yellow‑white color. Metallothionein, a presumptive marker of aggressive clinical behavior, is increased in the infiltrative variant.

Sclerosing type

The sclerosing category includes lesions which have also been referred to as fibrosing, scirrhous, desmoplastic and morpheic.

The uncommon 'field fire' type with central fibrosis resulting from regression should not be included in this category. Up to 5% of all basal cell carcinomas are of the sclerosing type.

The term 'keloidal' has been applied to basal cell carcinomas with thick sclerotic keloidal collagen bundles in the stroma.

Link

http://www.epathologies.com/pcoll/derm/p_ref/ca_baso_wee.htm
http://www.med.muni.cz/biomedjournal/pdf/2006/05/261_270.pdf

nodular basal cell carcinoma

2013-05-22T15:30:08Z

Nodular type (solid)

Definition: The solid variant, also known as the large nest type, accounts for approximately 70% of all cases. It is composed of islands of cells with peripheral palisading and a haphazard arrangement of the more central cells.

This histological type represents, according to various authors, 30 to 75
% of all BCC. This wide range is influenced to a certain extent by the assignment or exclusion of similar growth types.

The nodular histological type consists of cell islets with a typical peripheral palisading of the cells and chaotic arrangement of the cells in the central region. It can achieve a cystic appearance in microscopy in the case of necrosis of centrally located cells, next to which an accumulation of mucin occurs.

Sometimes the projections of the tumour cells produce a reticular formation. Some authors set apart this cystic and adenoid pattern as special types, other authors include these variants in the nodular variant due to the basic growth pattern.

The fibroepithelial variant is also often included in the nodular type, in which cell nests interconnected with thin strands of cells are lost in the abundant stroma.

Retraction spaces sometimes form between the tumor islands and the surrounding stroma. Ulceration may be present in larger lesions.

superficial basal cell carcinoma

2013-05-22T15:28:25Z

Superficial type (multicentric, multifocal)

This histological type, consisting of 10–15% of BCC is most frequently described in younger age categories. It consists of frequent small islets of basaloid tumour cells, well circumscribed against normal epithelia and in close contact but without apparent invasion; with papillary dermis.

The nests are often surrounded by thin strands of fibrous stroma with lymphocyte infiltrate and thin-walled vessels. Multifocal development of this type is sometimes called into question by some authors since three-dimensional reconstruction studies have shown that the cell nests, no matter how distant they are from each other, are connected by tiny projections.

From this finding the authors conclude a single-centre development of this type of BCC; in spite of this the synonym multicentric is still being used for the superficial type.

See also

cutaneous basal cell carcinoma

Links

http://www.med.muni.cz/biomedjournal/pdf/2006/05/261_270.pdf

ATG8

2013-05-22T12:00:40Z

Diagnostic use

autophagic vacuolar cardiomyopathy

Autophagic vacuolar cardiomyopathy is an underrecognized, but potentially fatal, complication of treatment with chloroquine (CQ) and its derivative hydroxychloroquine (HCQ), which are used as therapy for malaria and common connective tissue disorders.
Currently, the diagnosis of autophagic vacuolar cardiomyopathy is established through an endomyocardial biopsy and requires electron microscopy, which is not widely available and has a significant potential for sampling error.
Immunohistochemistry for autophagic markers LC3 (ATG8) and p62 (NUP62) can replace electron microscopy in the diagnosis of HCQ-induced and colchicine-induced autophagic vacuolar skeletal myopathies.
CQ-induced or HCQ-induced autophagic vacuolar cardiomyopathy is not universally fatal, but successful treatment requires early detection.

References

LC3 and p62 (NUP62) as Diagnostic Markers of Drug-induced Autophagic Vacuolar Cardiomyopathy: A Study of 3 Cases. Daniels BH, McComb RD, Mobley BC, Gultekin SH, Lee HS, Margeta M. Am J Surg Pathol. 2013 May 15. PMID: #23681079#

drug-induced autophagic vacuolar cardiomyopathy

2013-05-22T11:57:53Z

Autophagic vacuolar cardiomyopathy is an underrecognized, but potentially fatal, complication of treatment with chloroquine (CQ) and its derivative hydroxychloroquine (HCQ), which are used as therapy for malaria and common connective tissue disorders.

Currently, the diagnosis of autophagic vacuolar cardiomyopathy is established through an endomyocardial biopsy and requires electron microscopy, which is not widely available and has a significant potential for sampling error.

Immunohistochemistry for autophagic markers LC3 and p62 can replace electron microscopy in the diagnosis of HCQ-induced and colchicine-induced autophagic vacuolar skeletal myopathies.

CQ-induced or HCQ-induced autophagic vacuolar cardiomyopathy is not universally fatal, but successful treatment requires early detection.

References

LC3 and p62 as Diagnostic Markers of Drug-induced Autophagic Vacuolar Cardiomyopathy: A Study of 3 Cases. Daniels BH, McComb RD, Mobley BC, Gultekin SH, Lee HS, Margeta M. Am J Surg Pathol. 2013 May 15. PMID: #23681079#

NUP62

2013-05-22T11:57:19Z

info DKFZp547L134, FLJ20822, FLJ43869, IBSN, MGC841, "nuclear pore glycoprotein p62", p62, SNDI; info nucleoporin 62kDa

Diagnostic use

autophagic vacuolar cardiomyopathy

Autophagic vacuolar cardiomyopathy is an underrecognized, but potentially fatal, complication of treatment with chloroquine (CQ) and its derivative hydroxychloroquine (HCQ), which are used as therapy for malaria and common connective tissue disorders.
Currently, the diagnosis of autophagic vacuolar cardiomyopathy is established through an endomyocardial biopsy and requires electron microscopy, which is not widely available and has a significant potential for sampling error.
Immunohistochemistry for autophagic markers LC3 and p62 (NUP62) can replace electron microscopy in the diagnosis of HCQ-induced and colchicine-induced autophagic vacuolar skeletal myopathies.
CQ-induced or HCQ-induced autophagic vacuolar cardiomyopathy is not universally fatal, but successful treatment requires early detection.

References

cytoplasmic positivity of TTF-1

2013-05-22T09:24:34Z

cytoplasmic positivity of TTF1

eIHC

Cytoplasmic staining with TTF-1 has been little studied. This cytoplasmic staining is due to a cross-reacting antigen of 160 kd, which is not an alternative splicing product of TTF-115.

In a large series of consecutive cases, about 6% (23/361) of all tumours from a variety of sites showed cytoplasmic staining.

hepatocellular carcinoma
a minority of pulmonary adenocarcinomas show coarse granular cytoplasmic staining
occasionally in squamous carcinomas of the lung, head, neck and cervix
occasional positivity in oncocytic thyroid tumours
some gastrointestinal and pancreatic carcinoids
colonic adenocarcinoma
rather commonly in decalcified bone

perinuclear staining in :

small and large intestine
pancreatic ductal and acinar cells

Tumors

hepatocellular carcinoma

The binding of both thyroid transcription factor-1 and HepPar1 is to mitochondrial proteins in hepatocytes.
The staining is usually granular.
Staining is seen with a biotin-free protocol8, although several authors used a biotin-based system in combination with HIER: false perinuclear positivity due to endogenous biotin may sometimes appear.
The diffuse cytoplasmic staining of hepatocytes (and hepatocellular carcinoma) is seen only with clone 8G7G3/1 (DakoCytomation and others), not with clone SPT24 (NovoCastra).

CA-125

2013-05-22T09:01:39Z

CA-125 (cancer antigen 125 or carbohydrate antigen 125) also known as "mucin 16" or "MUC16" is a protein that in humans is encoded by the MUC16 gene.

MUC16 is a member of the mucin family glycoproteins.

CA-125 has found application as a tumor marker or biomarker that may be elevated in the blood of some patients with specific types of cancers, or other benign conditions.

mediastinal lymph nodes

2013-05-21T13:01:28Z

- Mediastinum