This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Feasibility and Therapeutic Efficacy of Ductoscopic Papilloma Extraction in Patients With Pathologic Nipple Discharge (NCT01901562), a na na study. The primary outcome is Number of Complete Ductoscopic Retrievals.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01901562 |
| Phase | NA |
| Condition | Breast Discharge Infected, Intraductal Papilloma of Breast |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 9 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Montefiore Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
The intended population was patients with pathologic nipple discharge who consented to ductoscopy and were diagnosed with a solitary papilloma within the discharging duct. The study description further distinguishes patients whose papilloma was identified ductoscopically as solitary and non-sessile.
Intervention
The intervention was an attempted ductoscopic papillectomy, using a ductoscopic basket as an endoscopic extraction instrument, for patients with a solitary non-sessile papilloma. The study was intended to assess the feasibility and therapeutic efficacy of that approach.
Comparator
There was no randomized or concurrent control group. Patients with ductoscopic findings other than a single non-sessile papilloma were to undergo standard ductoscopically guided microductectomy; this was a different management pathway, not a like-for-like control comparison.
Primary question
The primary question was whether complete ductoscopic retrieval of a papilloma could be achieved over 90% of enrolled patients diagnosed with a solitary papilloma, assessed at 6 months. The registry record says data related to the number of complete ductoscopic retrievals were not collected and analyzed, so that question remains unanswered by the posted results.
3. Trial Design
This was a prospective, single-group clinical trial of ductoscopic papillectomy for pathologic nipple discharge associated with a solitary papilloma in the discharging duct. The registry lists the phase and allocation as NA and masking as NONE. It lists the model as SINGLE GROUP, and there is no randomized comparison. The study is therefore not designed to estimate a treatment effect against a concurrent control group.
The planned clinical pathway depended on ductoscopic findings. Patients identified with a solitary non-sessile papilloma were to undergo an attempted ductoscopic papillectomy. Those with other ductoscopic findings were to undergo standard ductoscopically guided microductectomy. The stated aim included assessing whether the ductoscopic basket could be used for extraction without adverse events. Histopathological evaluation was planned to confirm the ductoscopic diagnosis and assess for malignant tissue.
The registry lists enrollment as 9. The recorded start date is 2013-09-27, the primary completion date is 2017-01-11, and the status is TERMINATED. The reason for termination is not reported in the registry record. The intended primary-outcome timeframe was 6 months. The registry record does not report a protocol-based sample-size justification, a planned interim analysis, or a statistical analysis plan.
The secondary outcomes concern cessation of nipple discharge and clinical recurrence of nipple discharge. The record lists 3 outcome measures and 0 analyses. No comparison between the intervention and microductectomy pathway should be inferred: the latter was not a control arm, and the trial's listed design is single-group.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Ductoscopic Papillectomy |
|---|---|
| STARTED | 9 |
| COMPLETED | 0 |
| NOT COMPLETED | 9 |
Reasons for not completing this period:
| Reason | Ductoscopic Papillectomy |
|---|---|
| Protocol Violation | 5 |
| Excluded intraoperatively | 4 |
Analysis population for the primary outcome, as defined in the registry: Data related to the number of complete ductoscopic retrievals was not collected and analyzed.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Ductoscopic Papillectomy |
|---|---|---|
| Participants analysed | 9 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 9 |
| Age, Categorical: >=65 years | Participants | 0 |
| Sex: Female, Male: Female | Participants | 9 |
| Sex: Female, Male: Male | Participants | 0 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 7 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 8 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 1 |
| Region of Enrollment: United States | participants | 9 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Complete Ductoscopic Retrievals, measured over 6 months.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was the number of complete ductoscopic retrievals, with a 6 months timeframe. Complete retrieval was defined in the registry description as total ductoscopic retrieval of a papilloma. The stated technical-success target was complete retrieval in over 90% of enrolled patients diagnosed with a solitary papilloma.
This endpoint was selected to address a feasibility question: whether the papilloma could be retrieved using ductoscopy and the basket extraction approach. A technical endpoint can describe whether a procedure accomplishes its immediate procedural aim, but it does not by itself establish improvement in symptoms, recurrence, or other patient outcomes. The listed secondary outcomes—cessation and clinical recurrence of nipple discharge—address clinical outcomes distinct from technical retrieval.
Crucially, the registry record states that data related to the number of complete ductoscopic retrievals were not collected and analyzed. It therefore contains no observed primary-endpoint count or estimate with which to assess the stated target. The record also does not report an analyzed estimate for the secondary outcomes.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical limitation is that the primary outcome is not available as an analyzed result. Although the registry describes complete ductoscopic retrieval and sets a technical-success target of over 90% among enrolled patients diagnosed with a solitary papilloma, it explicitly states that retrieval data were not collected and analyzed. The posted results therefore cannot show whether the target was met, missed, or approached.
The registry lists enrollment as 9, but that figure does not supply the outcome denominator. The number of participants diagnosed with a solitary papilloma, the number who underwent an attempted papillectomy, and the number with evaluable retrieval outcomes are not reported in the registry record. Without the outcome count and its denominator, no observed retrieval proportion can be interpreted. No confidence interval or other precision estimate for retrieval is reported either.
The secondary outcomes are the number of patients with cessation of nipple discharge and the number with clinical recurrence of nipple discharge. The record does not report analyzed results for either outcome. Thus, the registry does not establish the frequency of symptom cessation or recurrence, nor does it provide estimates of their precision or timing beyond the outcomes as named. Histopathological evaluation is described in the study plan, but analyzed findings are not reported in the registry record.
The safety figures are counts for the Ductoscopic Papillectomy group: 0 serious events among 4 at risk, 0 other events among 4 at risk, and 0 deaths. These should be read as the posted counts for those listed safety categories, not as proof that the procedure has no risk. The record does not describe the completeness of safety follow-up or explain how the listed at-risk group relates to enrollment or to the primary-outcome population.
Because this was a single-group study without a randomized control, any outcomes that had been recorded would describe the treated group rather than establish comparative effectiveness. The alternative microductectomy pathway was assigned according to ductoscopic findings, so it does not form a like-for-like control group. In this record, the missing primary and secondary outcome analyses further limit what can be concluded: the posted information documents the study's objectives and some safety counts, but not an analyzed efficacy result.
9. Statistical Methods Explained
What can a single-group design estimate?
In general, a single-group study can describe outcomes observed among participants who receive an intervention. For a binary outcome such as complete retrieval, an analysis would need to report the number with retrieval and the number assessed for that outcome. The resulting proportion would describe the observed group. It would not, by itself, estimate what would have happened under another procedure or without the intervention.
That distinction matters for this study. The registry lists a SINGLE GROUP model and no randomized allocation. The microductectomy pathway was intended for patients with ductoscopic findings other than a single non-sessile papilloma. Since the pathways applied to different clinical findings, their outcomes would not constitute a direct randomized comparison. Differences between the groups could reflect those different findings as well as the procedures.
Why does the primary outcome need a denominator?
In general, a proportion requires a clearly defined numerator and denominator. For this endpoint, the numerator would be complete ductoscopic retrievals and the denominator would be the relevant patients assessed for retrieval. The target in the registry is stated as over 90% of enrolled patients diagnosed with a solitary papilloma. To interpret that target, readers would need the number meeting the diagnosis criterion, the number undergoing attempted retrieval, the number with an outcome recorded, and the number with complete retrieval. Those counts are not reported in the registry record, which says the retrieval data were not collected and analyzed.
When some participants lack an outcome, the reason and extent of missingness affect interpretation. For example, a missing outcome caused by a procedure not being attempted is not necessarily equivalent to a recorded failure, and excluding missing outcomes can produce a different estimate from treating them as failures. These are general analysis considerations, not descriptions of what happened in this trial; the registry record does not report the relevant participant flow or missing-data handling.
How should precision be assessed?
In general, a confidence interval expresses the uncertainty around an estimate under a statistical model. For a proportion, it would communicate how imprecisely the observed retrieval frequency is estimated, given the available outcome data. It does not correct for biased selection, missing outcomes, or a lack of a control group. Here, no primary retrieval estimate or confidence interval is reported, so the precision of that outcome cannot be assessed from the registry record.
A p-value, when used, addresses compatibility between data and a specified statistical null model; it is not a measure of clinical importance or proof that a result is true. The record lists 0 analyses and does not report a primary-outcome test or p-value. Consequently, there is no inferential test to interpret for the main endpoint.
What do the planning illustrations mean?
In general, sample-size calculations describe how much information a future study might require under stated assumptions. The registry's planning description specifies a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect; for time-to-event tables, the stated quantity is total events, while other tables use participants per arm. These are planning assumptions, not evidence that the actual trial used a two-arm design.
The study itself is listed as single-group. A two-arm, equal-allocation planning illustration should therefore not be mistaken for the trial's design, nor does it create a control group in the observed study. The registry does not report a protocol sample-size justification. Any sample-size figures under these assumptions are planning illustrations, not observed power. In general, observed power calculated after a study is complete is not a substitute for reporting an effect estimate and its uncertainty.
Why do over-dispersion and model choice matter?
In general, over-dispersion occurs when observed variation is greater than a statistical model expects. It can make standard errors too small if a model assumes less variation than the data contain. Model choice should reflect the outcome and design: a binary retrieval outcome, a count of events, and time until recurrence do not necessarily call for the same analysis. The registry record does not report an analysis model, an over-dispersion assessment, or a time-to-event analysis. These concepts therefore explain general considerations rather than methods documented for this study.
Overall, the record supports a description of the intended endpoint and design, but not a statistical estimate of technical success. Without analyzed outcome counts, a denominator, and an uncertainty estimate, the technical target cannot be evaluated from the posted results.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 3 outcome measures: the primary measure of complete ductoscopic retrieval and secondary measures concerning cessation and clinical recurrence of nipple discharge. Considering multiple outcomes raises a general multiplicity issue: the more outcome tests conducted, the greater the chance of a false-positive finding if each is interpreted independently. A prespecified hierarchy or adjustment can address that issue, but the registry record does not report a multiplicity plan or the statistical analysis plan.
The record lists 0 analyses. It does not report analyzed results for the primary outcome or either secondary outcome, nor does it report the outcome-specific denominators or analysis populations. The primary outcome description specifically says that retrieval data were not collected and analyzed. The record does not explain whether secondary outcome data were collected, how any missing values were handled, or which participants would be included in an analysis.
In general, an analysis population should be defined in relation to the study question. For a procedural feasibility endpoint, relevant distinctions can include participants diagnosed with the target finding, those who underwent an attempted procedure, and those with an outcome assessed. Those distinctions are important because the stated primary target applies to patients diagnosed with a solitary papilloma, while enrollment alone does not identify that subgroup. The registry record does not report the counts needed to define or compare these populations.
No assumptions about missingness, exclusions, or multiplicity adjustment can be made from the available record. Without these details and the outcome analyses, statistical uncertainty and the consistency of any findings across outcomes cannot be evaluated.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Ductoscopic Papillectomy | 0 | 4 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Ductoscopic Papillectomy | 0 of 4 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Ductoscopic Papillectomy | 0 of 4 |
The registry reports safety counts for the Ductoscopic Papillectomy group. The serious-event figures are 0 affected among 4 at risk; the other-event figures are 0 affected among 4 at risk; deaths are 0. These are counts as recorded, and no additional rate or percentage is needed to read them.
In general, observing no events in a group does not prove that an intervention has no risk. The amount of uncertainty depends on how many participants were assessed, the length and completeness of follow-up, and how events were defined and collected. The registry record does not report enough detail to assess those features fully. It also does not explain the relationship between the safety at-risk group and the overall enrollment or the primary-outcome population.
The record lists no top serious-event terms. That is consistent with the posted count of 0 serious events in the listed group; it should not be interpreted as evidence that all possible adverse events were systematically ruled out. These safety figures are descriptive and do not support a comparison with microductectomy or another control group.
12. What the Result Does, and Does Not, Mean
The record establishes that a prospective, single-group study was registered to investigate ductoscopic papillectomy for patients with pathologic nipple discharge and a solitary papilloma in the discharging duct. Its primary technical question concerned complete ductoscopic retrieval, with a stated target of over 90% among enrolled patients diagnosed with a solitary papilloma and a 6 months timeframe.
It does not establish whether that technical target was achieved. The registry explicitly states that retrieval data were not collected and analyzed, and it reports no primary-outcome estimate or precision measure. The registry also names cessation and clinical recurrence of nipple discharge as secondary outcomes but does not report analyzed results for them. The intended histopathological assessment is described, but its findings are not reported in the registry record.
The safety counts are limited to the listed group and categories: 0 serious events among 4 at risk, 0 other events among 4 at risk, and 0 deaths. They are not a comparative safety estimate, and they do not establish that adverse events could not occur.
More generally, a single-group study can describe outcomes in the studied group, but cannot isolate an intervention's effect from other explanations as a randomized comparison can. Here, the alternative microductectomy pathway was intended for patients with different ductoscopic findings, so it is not a direct control group. The record's enrollment figure does not resolve the missing outcome denominator or show how many patients were eligible for the attempted papillectomy.
The appropriate interpretation is therefore narrow: the registry documents the study's rationale, intended pathway, target endpoint, and limited safety counts. It does not provide analyzed evidence to determine technical success, symptom outcomes, comparative benefit, or the precision of an efficacy estimate.
13. Why This Trial Matters Statistically
This trial illustrates why a clearly described endpoint is not the same as an available result. The registry defines complete ductoscopic retrieval as the technical outcome and states a target of over 90% in patients diagnosed with a solitary papilloma. Yet the record says the retrieval data were not collected and analyzed. Without an outcome count and denominator, even a well-defined endpoint cannot answer the study's central statistical question.
The distinction between feasibility and therapeutic efficacy is also important. Technical retrieval asks whether a papilloma was removed by the procedure. Cessation and recurrence of nipple discharge are separate clinical outcomes. Evidence about one does not automatically answer the others. The registry names those secondary outcomes, but reports no analyses for them.
The design further shapes what could be learned. A single-group study may describe outcomes, but lacks a randomized comparison for separating a procedure's contribution from other factors. The microductectomy pathway was intended for patients with findings different from those selected for attempted papillectomy, so it cannot serve as a like-for-like comparison.
Finally, the posted safety counts are useful only within their stated scope. Zero recorded events in the listed at-risk group is not the same as proof of no risk, and the record does not fully describe follow-up or the relationship between that group and enrollment. Together, these features show why statistical interpretation depends not only on an endpoint definition, but also on collected outcomes, transparent denominators, suitable comparisons, and enough information to judge uncertainty.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main trial-specific limitation is that the primary outcome was not collected and analyzed, according to the registry record. As a result, no observed complete-retrieval count, denominator, proportion, or confidence interval is available. The stated technical-success target cannot be evaluated.
The registry lists enrollment as 9, but does not report how many patients were diagnosed with a solitary papilloma, how many had a solitary non-sessile papilloma, or how many underwent an attempted ductoscopic papillectomy. These distinctions matter because the planned procedure and primary target applied to a defined subgroup, not necessarily to all enrolled patients.
The record lists secondary outcomes for cessation and recurrence of nipple discharge without analyzed results or details of their assessment. It also does not report histopathological findings, participant flow, reasons for missing outcomes, or the reason for termination. No protocol-based sample-size justification, statistical analysis plan, or multiplicity approach is reported in the registry record.
The study is single-group, with no randomized control. The microductectomy pathway was intended for patients with other ductoscopic findings, so outcome differences between pathways would not provide a straightforward treatment comparison. Finally, the safety record gives counts for a listed at-risk group, but does not explain its relation to enrollment or describe the completeness of safety follow-up.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Feasibility and Therapeutic Efficacy of Ductoscopic Papilloma Extraction in Patients With Pathologic Nipple Discharge — NCT01901562.
- Registry record last updated 2023-11-09; status last verified 2023-11.
- Results first posted 2023-11-09.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry record describes a prospective, single-group study of ductoscopic papillectomy for pathologic nipple discharge associated with a solitary papilloma in the discharging duct. The sponsor is Montefiore Medical Center. Phase and allocation are listed as NA, and masking as NONE.
Enrollment is listed as 9. The start date is 2013-09-27, the primary completion date is 2017-01-11, and the status is TERMINATED. The reason for termination is not reported in the registry record.
The primary outcome was complete ductoscopic retrieval, with a 6 months timeframe and a stated technical-success target of over 90% among patients diagnosed with a solitary papilloma. The record says retrieval data were not collected and analyzed. The listed secondary outcomes concern cessation and recurrence of nipple discharge; analyzed results are not reported. The safety counts are 0 serious events among 4 at risk, 0 other events among 4 at risk, and 0 deaths.