Immunohistochemistry/Special Stain Addendum

Report Type: Addendum Report – Immunohistochemistry/Special Stain

Accession Number: [Accession number] (If unavailable, enter [REQUIRED] rather than omitting.)

Addendum Number: [Addendum number] (Include only if sequential addenda exist for this case.)

Original Report Date: [Original report date] (If unavailable, enter [REQUIRED] rather than omitting.)

Patient Name: [Patient name]

MRN: [Medical record number]

Specimen: [Anatomic site and part designation] (If unavailable, enter [REQUIRED] rather than omitting.)

Reason for Addendum

[Rationale for post-sign-out ancillary stains and the clinical or morphologic question addressed] (1–2 sentences.)

Material Evaluated

[Part letter, block ID(s), slide level(s); for cytology, cell block ID] (Note pertinent pre-analytic factors affecting interpretation such as decalcification, crush artifact, scant tumor, or necrosis.)

Stain Results

Stain	Clone	Block	Result	Controls
[Antibody or special stain name]	[Clone / N/A]	[Block ID]	[Positive / Negative / Equivocal] with [localization, intensity, distribution]	[Adequate / Inadequate]

(Add rows as needed. For IHC, specify localization [nuclear/cytoplasmic/membranous], intensity [weak/moderate/strong], and distribution [focal/diffuse/percent positive] when clinically meaningful. For predictive biomarkers, include scoring system name, numeric score, and interpretive category. For organism stains, describe morphology sufficient for broad categorization; if negative, state "No [organism type] identified." Note internal control status when results are negative or weak. For a single stain, a narrative paragraph may replace the table but must include the same elements.)

[Outside laboratory name and location] (Include only if any stain was performed at an outside laboratory.)

[Global control statement] (Example: "Appropriate controls demonstrate expected reactivity." Document any technical limitations such as suboptimal staining, tissue exhaustion, or failed controls requiring repeat.)

Interpretation

[Synthesis of staining profile and diagnostic implications] (2–5 sentences. State how results support or exclude specific entities. Correlate with H&E morphology and clinical context. Recommend additional testing if indicated.)

Impact on Diagnosis

[Final diagnosis remains unchanged. / Findings support the previously rendered diagnosis of [diagnosis].] (Select one statement. If results contradict or materially revise the original diagnosis, do not use this addendum format; issue an Amended/Corrected Report per institutional policy.)

Communication

(Include only if results significantly alter diagnosis, prognosis, or treatment, or represent unexpected time-sensitive findings.)

• Person Contacted: [Name and role/service]
• Date/Time: [Date and time of contact]
• Method: [Phone / page / in-person / EHR message]
• Information Communicated: [Brief summary]
• Communicated By: [Name of communicating pathologist]

Disclaimers

(Include only when applicable.)

• [ASR or LDT disclaimer text per institutional/regulatory requirements]
• [Negative stains do not exclude infection; correlate with culture and clinical findings as indicated.] (Include for negative organism stains.)

Sign-Out

Pathologist: [Signing pathologist name]

Date/Time: [Date and time of addendum sign-out]

Original Pathologist of Record: [Name] (Include only if different from signing pathologist.)