Metaplastic breast carcinoma: the decisions you may face

Cancer page →Second-opinion finder →

2 treatment settings, 2 with more than one named option. Each section lays out the options the standard of care names, what each is for, the trials behind them with their recorded results, the side effects and cautions on record, and questions to ask. Built from the cancer page's standard-of-care rows; nothing here is advice for your case.

Early / localised

Early disease

3 optionsCompare side by side →

Surgery and radiotherapy, with chemotherapy as for triple-negative disease of no special type; chemotherapy and radiotherapy were associated with better survival in the national database, and axillary dissection was not. Low-grade adenosquamous and fibromatosis-like forms are treated by surgery alone in the European working group's consensus.

The options, in plain words

Sentinel lymph node biopsyStandard of care

Removing just the first lymph node a tumour drains to, instead of all of them, to check for spread.

Avoids lymphoedema from full dissection

CarboplatinApprovedCytotoxic chemotherapy (platinum)

Carboplatin is a platinum chemotherapy that crosslinks DNA; it is part of the standard pre-surgery regimen for triple-negative breast cancer.

Paclitaxel / nab-paclitaxelApprovedCytotoxic chemotherapy (taxane)

A microtubule poison discovered in the Pacific yew tree, among the most used chemotherapies in breast, lung, and ovarian cancer.

Also referenced:MastectomyLumpectomy (breast-conserving surgery)

The evidence behind it

No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.

The main trade-offs on record

Sentinel lymph node biopsy

False negatives in ~5-10%

Carboplatin all recorded rates →

Dose by Calvert formula using GFR (see the calculators).

Questions to ask about this decision

Between Sentinel lymph node biopsy, Carboplatin and Paclitaxel / nab-paclitaxel, which do you recommend for me, and what about my case would make you choose differently?
Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?
Why: The aim shapes how much side effect and disruption is worth accepting.
What happens if I delay, or decline this step for now? Is the decision reversible?
Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
For my situation (early disease), which of the standard options do you recommend and why?
Why: Guideline options include: Surgery and radiotherapy, with chemotherapy as for triple-negative disease of no special type; chemotherapy and radiotherapy were associated with better survival in the national database, and axillary dissection was not. Low-grade adenosquamous and fibromatosis-like forms are treated by surgery alone in the European working group's consensus.
Am I a candidate for Carboplatin, Paclitaxel / nab-paclitaxel, and what side effects should I expect?
Why: Knowing the expected toxicities helps you plan work, family, and supportive care.

Add these to your appointment list, or take the full question set for this cancer.

Advanced, first line

Advanced disease

2 optionsCompare side by side →

As for metastatic triple-negative disease (pembrolizumab where PD-L1 positive, TROP2 ADCs); response to chemotherapy is poorer than in other triple-negative cancers.

The options, in plain words

PembrolizumabApprovedMonoclonal antibody (anti-PD-1)

Pembrolizumab is a PD-1 blocking antibody approved in more than 40 settings, from melanoma and lung cancer to the first tumour-agnostic approval for mismatch-repair-deficient tumours in 2017, and before and after surgery in triple-negative breast cancer. A subcutaneous form arrived in 2025, and it is the backbone partner for ADCs and personalised neoantigen vaccines.

Sacituzumab govitecanApprovedADC

The first TROP2-targeted ADC. It delivers a strong chemotherapy directly to breast and bladder cancer cells and is now a first-line option in triple-negative breast cancer.

The evidence behind it

No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.

The main trade-offs on record

Pembrolizumab all recorded rates →

Side effect	Any grade	Grade 3+
Hypothyroidism (immune-mediated) · Pooled monotherapy data, >2,800 patients	8%	-
Pneumonitis (immune-mediated) · Pooled monotherapy data, >2,800 patients	3.4%	-
Colitis (immune-mediated) · Pooled monotherapy data, >2,800 patients	1.7%	-
Hepatitis (immune-mediated) · Pooled monotherapy data, >2,800 patients	0.7%	-

No pharmacokinetic interactions expected (antibody). See the irAE guide for toxicity management.

Rates from the label or pivotal trial as recorded on the product page; each grade 3+ figure links to its source.

Sacituzumab govitecan all recorded rates →

Side effect	Any grade	Grade 3+
Neutropenia (grade 3 or higher) · ASCENT, sacituzumab arm; 33 percent with chemotherapy	-	51%
Neutropenia · ASCENT, Trodelvy arm, n=258	78%	49%
Diarrhoea · ASCENT, Trodelvy arm, n=258	59%	11%
Diarrhoea (grade 3 or higher) · ASCENT; below 1 percent with chemotherapy	-	10%

UGT1A1*28 homozygotes: higher neutropenia risk; G-CSF prophylaxis is often used.

Rates from the label or pivotal trial as recorded on the product page; each grade 3+ figure links to its source.

Questions to ask about this decision

Between Pembrolizumab and Sacituzumab govitecan, which do you recommend for me, and what about my case would make you choose differently?
Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?
Why: The aim shapes how much side effect and disruption is worth accepting.
Which side effects of Pembrolizumab or Sacituzumab govitecan are most likely for me, which are reversible, and which would make us stop?
Why: The recorded rates below come from labels and trials; your own risk depends on dose, other medicines and your health.
What happens if I delay, or decline this step for now? Is the decision reversible?
Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
For my situation (advanced disease), which of the standard options do you recommend and why?
Why: Guideline options include: As for metastatic triple-negative disease (pembrolizumab where PD-L1 positive, TROP2 ADCs); response to chemotherapy is poorer than in other triple-negative cancers.
Am I a candidate for Pembrolizumab, Sacituzumab govitecan, and what side effects should I expect?
Why: Knowing the expected toxicities helps you plan work, family, and supportive care.

Add these to your appointment list, or take the full question set for this cancer.

How to read this page. Options and results come from OnCo records with their sources; the settings are the standard-of-care rows on the cancer page, and the lines of therapy are on the sequencing grid. Where a setting names one path, the choice is usually about timing, trials and where to be treated: see expert centres. OnCo is orientation, not medical advice.

Living with cancer·Standard of care

Metaplastic breast carcinoma: the decisions you may face

Cancer page →Second-opinion finder →

Early / localised

Early disease

3 optionsCompare side by side →

The options, in plain words

Sentinel lymph node biopsyStandard of care

Removing just the first lymph node a tumour drains to, instead of all of them, to check for spread.

Avoids lymphoedema from full dissection

CarboplatinApprovedCytotoxic chemotherapy (platinum)

Carboplatin is a platinum chemotherapy that crosslinks DNA; it is part of the standard pre-surgery regimen for triple-negative breast cancer.

Paclitaxel / nab-paclitaxelApprovedCytotoxic chemotherapy (taxane)

A microtubule poison discovered in the Pacific yew tree, among the most used chemotherapies in breast, lung, and ovarian cancer.

Also referenced:MastectomyLumpectomy (breast-conserving surgery)

The evidence behind it

No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.

The main trade-offs on record

Sentinel lymph node biopsy

False negatives in ~5-10%

Carboplatin all recorded rates →

Dose by Calvert formula using GFR (see the calculators).

Questions to ask about this decision

Between Sentinel lymph node biopsy, Carboplatin and Paclitaxel / nab-paclitaxel, which do you recommend for me, and what about my case would make you choose differently?
Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?
Why: The aim shapes how much side effect and disruption is worth accepting.
What happens if I delay, or decline this step for now? Is the decision reversible?
Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
For my situation (early disease), which of the standard options do you recommend and why?
Why: Guideline options include: Surgery and radiotherapy, with chemotherapy as for triple-negative disease of no special type; chemotherapy and radiotherapy were associated with better survival in the national database, and axillary dissection was not. Low-grade adenosquamous and fibromatosis-like forms are treated by surgery alone in the European working group's consensus.
Am I a candidate for Carboplatin, Paclitaxel / nab-paclitaxel, and what side effects should I expect?
Why: Knowing the expected toxicities helps you plan work, family, and supportive care.

Add these to your appointment list, or take the full question set for this cancer.

Advanced, first line

Advanced disease

2 optionsCompare side by side →

As for metastatic triple-negative disease (pembrolizumab where PD-L1 positive, TROP2 ADCs); response to chemotherapy is poorer than in other triple-negative cancers.

The options, in plain words

PembrolizumabApprovedMonoclonal antibody (anti-PD-1)

Sacituzumab govitecanApprovedADC

The first TROP2-targeted ADC. It delivers a strong chemotherapy directly to breast and bladder cancer cells and is now a first-line option in triple-negative breast cancer.

The evidence behind it

No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.

The main trade-offs on record

Pembrolizumab all recorded rates →

Side effect	Any grade	Grade 3+
Hypothyroidism (immune-mediated) · Pooled monotherapy data, >2,800 patients	8%	-
Pneumonitis (immune-mediated) · Pooled monotherapy data, >2,800 patients	3.4%	-
Colitis (immune-mediated) · Pooled monotherapy data, >2,800 patients	1.7%	-
Hepatitis (immune-mediated) · Pooled monotherapy data, >2,800 patients	0.7%	-

No pharmacokinetic interactions expected (antibody). See the irAE guide for toxicity management.

Rates from the label or pivotal trial as recorded on the product page; each grade 3+ figure links to its source.

Sacituzumab govitecan all recorded rates →

Side effect	Any grade	Grade 3+
Neutropenia (grade 3 or higher) · ASCENT, sacituzumab arm; 33 percent with chemotherapy	-	51%
Neutropenia · ASCENT, Trodelvy arm, n=258	78%	49%
Diarrhoea · ASCENT, Trodelvy arm, n=258	59%	11%
Diarrhoea (grade 3 or higher) · ASCENT; below 1 percent with chemotherapy	-	10%

UGT1A1*28 homozygotes: higher neutropenia risk; G-CSF prophylaxis is often used.

Rates from the label or pivotal trial as recorded on the product page; each grade 3+ figure links to its source.

Questions to ask about this decision

Between Pembrolizumab and Sacituzumab govitecan, which do you recommend for me, and what about my case would make you choose differently?
Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?
Why: The aim shapes how much side effect and disruption is worth accepting.
Which side effects of Pembrolizumab or Sacituzumab govitecan are most likely for me, which are reversible, and which would make us stop?
Why: The recorded rates below come from labels and trials; your own risk depends on dose, other medicines and your health.
What happens if I delay, or decline this step for now? Is the decision reversible?
Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
For my situation (advanced disease), which of the standard options do you recommend and why?
Why: Guideline options include: As for metastatic triple-negative disease (pembrolizumab where PD-L1 positive, TROP2 ADCs); response to chemotherapy is poorer than in other triple-negative cancers.
Am I a candidate for Pembrolizumab, Sacituzumab govitecan, and what side effects should I expect?
Why: Knowing the expected toxicities helps you plan work, family, and supportive care.

Add these to your appointment list, or take the full question set for this cancer.