Principles

Pathology can only answer the question if it is clearly framed and the specimen correctly oriented.
Communicate clinically relevant detail: prior treatment, clinical impression, intended definitive margin, anatomical position (peri-orbital, peri-auricular, etc.).
Use a consistent orientation convention agreed locally with pathology — typically suture-at-superior (12 o'clock) for ellipses, or two-suture (1× superior, 1× lateral / longer arm) for complex shapes.
Diagrammatic specimen map for irregular / complex specimens (Mohs, multi-fragment excision, en-face permanent sections).

Standard conventions

Single suture: place at superior (12 o'clock) margin. State this on the request form.
Two-suture orientation:
- Short stitch = superior; long stitch = lateral / 3 o'clock.
- Equivalent variants — short for short (cranial), long for long (lateral).
Ink convention: ideally, in addition to suture, ink the deep surface and one specific lateral edge with coloured ink as defined in your protocol; pathologist preserves this in cut-up.
Photograph the specimen on a sterile drape before sending — labelled with patient ID and orientation.
Defect map: diagrammatic representation of defect, sutures and orientation; particularly important for Mohs and multi-stage excision.
Specimen pot: appropriate fixative volume (10% neutral buffered formalin, ≥10× tissue volume; PBS if molecular testing planned).

Patient demographics + NHS number.
Anatomical site (specific, with side; e.g. "right lower eyelid medial canthus").
Clinical question — confirm diagnosis vs assess margins vs grade.
Clinical impression / differential.
Prior treatment: biopsy, RT, topical 5-FU / imiquimod, cryotherapy, Mohs stage.
Excision type — diagnostic punch, shave, incisional, complete WLE, Mohs.
Orientation legend.
Intended margin distance.
Special tests: BRAF V600, PD-L1, NRAS, mismatch-repair, T-cell receptor gene rearrangement.
Urgency flag if 2-week-wait or MDT-deadline-driven.
Operator's direct contact details.

UK RCPath publish skin-cancer datasets specifying minimum content of histopathology reports:
- Cutaneous melanoma dataset — Breslow, ulceration, mitotic rate, LVI, perineural invasion, microsatellites, regression, TILs, transected base, peripheral / deep margins, pT stage AJCC 8.
- cSCC dataset — invasion depth, level (Clark), differentiation, PNI calibre & named-nerve, LVI, peripheral / deep margins, AJCC 8 + BWH staging.
- BCC dataset — subtype (nodular, superficial, infiltrative, morphoeic, basosquamous), depth, PNI, peripheral / deep margins.
Surgeons should expect these data elements; missing items should prompt MDT clarification.
Final reports should identify the RCPath dataset / local synoptic proforma and TNM appendix used.

Speak with pathology pre-operatively for complex or unusual cases (e.g. desmoplastic melanoma, DFSP, suspected MCC).
Bring relevant slides / digital images to MDT; do not rely solely on text reports for complex tumours.
Joint surgeon-pathologist consensus on positive / close margins before booking re-excision.
Document agreed plan in MDT minutes with named lead.