Case Number : 112 Posted By: Guest

Richard Carr - Warwick (UK) Wrote:

Re: Squamous morules refers to distinctive round "balls" of squamous cells with abundant eosinophilic cytoplasm. Often in the same case you will see that the squamous morule has central bright orange keratin (when section through the centre). We have been observing very rounded squamoid "balls" (i.e. squamous morules) in a number of different cutanaeous adnexal tumours most commonly of follicular derivation notably a variant of keratotic BCC that we call squamous morular variant of keratotic BCC that is often associated with clear cell changes and can be easily confused with hidradenoma. Nearly all follicular SCC have squamous morules with the bright orange tricholemmal type keratinisation characteristic of these lesions. It seems that when tumours derived from the follicles (i.e. BCC and infundibular/tricholemmal SCC) keratinise that exhibit the same type of central rounded pilar keratinisation and squamous morular changes). We can also see this keratinisation in inverted follicular keratosis, tricholemmoma, pilar sheath acanthoma, hidradenoma and porocarcinoma so it is by no means specific but as I say quite characteristic of the follicular SCC and one variant of BCC. The squamous pearls in SCC are more oval than rounded and not so pilar in type and the squamous eddies characteristic of inverted folliclar keratosis/irritated SEBK tend to be tighter swirls with more evident angulation of cells and prominent desmosomal attachments. Squamous eddies almost always have more uniform more basaloid cells at the peripheral and lack the prominent atypia (at least focally) seen in the follicular SCC. We planned to publish our observations on to publish a paper (one day!) on cutaneous tumours with "squamous morular" changes. We used that term because of the squamous morules closely resemble those commonly seen in endometrial adenocarcinomas. Clearly a study of differential keratins on these lesions would be most interesting. Regards Richard

Submitted on 15/11/2010 11:43
________________________________________
Richard Carr - Warwick (UK) Wrote:

My diagnosis was alomost instantaneous on the field of probable follicular SCC. I was wondering if it was one of several cases I have sent to Phillip but did not want to spoil the fun. Remember the follicle does have an infundibulum that keratinises with keratohyaline granules but do observe the striking abundant eosinophilic cytoplasm with relatively abrupt solid bright orange pilar keratinisation that dominates here. To diagnose a follicular (tricholemmal) variant of SCC you need a low power to show the point of origins of the tumour within the follicular infundibular unit. The tumour has very sharp connections with the epidermis at the infundibulum and lacks interfollicular bowenoid actinic keratosis. Other common features are a lobulated expanding profile, central tricholemmal type keratinisation (all cases), accumulation of stromal type mucin within the centre of acantholytic spaces ("follicular mucinosis") and often subtle peripheral palisading. Tumours can have quite basaloid peripheries but lack the prominent peripheral palisade and stromal mucin in retraction spaces seen in BCC and are not diffusely BerEP4 positive. We just presented our experience with 59 cases at the International Society of Dermpath meeting in Barcelona and we believe that this follicular (infundibular/tricholemmal) variant of SCC is massively under-recognised. Reconition of the circumscribed variant is probably useful to the patient as it probably does not carry much in the way of metastatic potential and patients can probably be discharged as for the management of BCC. Note that the patients in our series have the same demographic as SCC i.e. tumours favour the sun-damaged skin of the head and neck in the elderly with a male predominance. Also many lesions clinically are diagnosed as ?BCC because of the rather nodular expansile process. Keratoacanthoma does come in to the differential diagnosis of this variant of SCC but KA has a very typical history of rapid initial growth. The low power is very important in making the diagnosis but even this field is very typical. Regards to all. Richard

Submitted on 15/11/2010 09:29
________________________________________
Francisco Vilchez - () Wrote:

Squamous cell carcinoma

Submitted on 12/11/2010 23:53
________________________________________
Eman El-Nabarawy - Cairo University (Egypt) Wrote:

Dear sir, I can see keratohyaline granules in the island of keratinization,I do think (from my little knowledge)that keratohyaline granules not present in trichilemmal keratinization. Could we have some explanation please, Thanks.

Submitted on 12/11/2010 19:32
________________________________________
Phillip McKee - Overseas consultations (Sedona, Arizona, USA) Wrote:

This case is not as easy as it sems. Note that the keratinization is pilar in type and not epidermoid. The case come from a collection of "Follicular SCC's" that Richard Carr has been studying and has shown me quite a number of them. It does seem to be a real entity. It lacks the clear cells, basement membrane thickening etc of trichilemmal Ca. I do not know whether this variant behaves in any way different from conventioanl SCC. Have a great weekend. Phillip

Submitted on 12/11/2010 18:54
________________________________________
Marwa Fawzi - Dermatology Department, Faculty of Medicine, Cairo University (Egypt) Wrote:

Verrucous carcinoma [ bulbous processes showing a characteristic pushing margin in contrast to the infiltrative border of an ordinary SCC ]

Submitted on 12/11/2010 14:22
________________________________________
Rodrigo Restrepo - UPB/CES (Mdlln. Col) Wrote:

SCC

Submitted on 12/11/2010 10:53
________________________________________
Carlos B - Trainee (Spain) Wrote:

Moderate to poorly differenitated SCC. It is good to seem more straight forward cases

Submitted on 12/11/2010 09:35
________________________________________
Eman El-Nabarawy - Cairo University (Egypt) Wrote:

SCC arising in Bowen's disease.

Submitted on 12/11/2010 09:11
________________________________________
Mona Abdel-Halim - Dermatology Department, Faculty of Medicine, Cairo University (Egypt) Wrote:

Infiltrative border of a malignant epithelial neoplasm. Squamoid cells, squamous morules (rounded foci of keratinization, not the typical horn pearls of SCC), and a squamous eddy. Cells are not clear, could not identify a glassy basement membrane. I think there is a punched out rounded intracytoplasmic lumen in the right lower quarter. I am thinking of a poorly differentiated porocarcinoma as the cells are showing prominent squamous differentiation.

Submitted on 12/11/2010 08:34
________________________________________
Phillip McKee - Overseas consultations (Arizona, USA) Wrote:

This case was kindly shared with me by Dr Richard Carr.

Submitted on 12/11/2010 08:33
________________________________________